# U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/crs%3AR44108

## Record

- **Collection:** Congressional research report
- **Document type:** CRS Report
- **Published:** July 15, 2015
- **Citation:** R44108

## Text

U.S. Command and Control and Intelligence,
Surveillance, and Reconnaissance Aircraft
(name redacted)
US Air Force Fellow
July 15, 2015

Congressional Research Service
7-....
www.crs.gov
R44108

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Summary
The fleet of manned aircraft accomplishing the Department of Defense’s (DOD’s) Command and
Control (C2) and Intelligence, Surveillance, and Reconnaissance (ISR) missions for the joint
military community (E-8, E-3, RC-135, WC-135, OC-135, and E-6) is primarily based on Boeing
707 aircraft procured from the 1960s to the early 1990s. As the age of these legacy C2ISR aircraft
increases, understanding the Air Force and Navy modernization and recapitalization plans is
likely important for Congress. This report examines the Air Force’s and Navy’s current
sustainment, modernization, and recapitalization efforts for these Boeing 707-based aircraft, and
issues Congress may take into account when considering appropriating funds for continued
sustainment and modernization of these aircraft versus funding for recapitalization of these
missions to new aircraft.
This report addresses potential congressional oversight and appropriations concerns for the
sustainment, modernization, and recapitalization of the DOD’s Boeing 707-based legacy C2ISR
aircraft fleet. It does not address options for recapitalization currently being offered by industry to
other countries. Congress has the authority to approve, reject, or modify Air Force and Navy
funding requests for C2ISR aircraft sustainment, modernization, and recapitalization, as well as
oversight of the nation’s C2ISR requirements and capabilities. Congress’s decisions on
appropriations for the C2ISR force could impact the nation’s C2ISR capabilities and have
additional consequences for the U.S. aerospace industry.
The starting point for Congress’s debate on legacy C2ISR sustainment, modernization, and
recapitalization is the existing Boeing 707-based C2ISR fleet consisting of 89 operational aircraft,
which includes
•

16 E-8C Joint Surveillance Targeting Attack Radar System (JSTARS) aircraft
providing airborne battle management, command and control, intelligence,
surveillance, and reconnaissance;

•

31 E-3 Sentry Airborne Warning and Control (AWACS) aircraft with integrated
command and control battle management (C2BM), surveillance, target detection,
and tracking;

•

17 RC-135V/W RIVET JOINT aircraft supporting theater and national level
forces with near real time on-scene intelligence collection, analysis, and
dissemination capabilities;

•

2 RC-135U COMBAT SENT aircraft that locate and identify foreign military
land, naval, and airborne radar signals to determine detailed operating
characteristics and capabilities of those systems;

•

3 RC-135S COBRA BALL aircraft that collect optical and electronic data on
ballistic missile targets;

•

2 WC-135 Constant Phoenix atmospheric collection aircraft that collect
particulate and gaseous effluents and debris from accessible regions of the
atmosphere supporting the Limited Nuclear Test Ban Treaty of 1963;

•

2 OC-135B Open Skies aircraft that perform unarmed observation flights over
participating parties of the Open Skies Treaty, and

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U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

•

16 E-6B Mercury communications relay and strategic airborne command post
aircraft.

Potential congressional oversight and appropriations concerns for the sustainment, modernization,
and/or recapitalization of the DOD’s Boeing 707-based legacy C2ISR aircraft fleet include
•

a potential shortfall in C2ISR capabilities if there is a funding gap for
sustainment and upgrades that would keep the weapon systems viable until they
are recapitalized;

•

ascertaining DOD, Air Force, and Navy priorities for sustainment,
modernization, and recapitalization;

•

determining if modernization efforts allow for delayed recapitalization efforts;

•

consideration of shifting some of the legacy C2ISR missions to remotely piloted
aircraft;

•

the potential implications of reduced legacy C2ISR aircraft sustainment and
modernization, and subsequent diminishing numbers of airframes on any future
rounds of base realignment and closure efforts; and

•

the ability of the nation’s industrial base to sustain the legacy C2ISR aircraft
force.

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Contents
Introduction...................................................................................................................................... 1
Background ...................................................................................................................................... 2
Dash 80/Boeing 707 .................................................................................................................. 2
Current Boeing 707-Based DOD C2ISR Force ......................................................................... 2
E-8C Joint Surveillance Targeting Attack Radar System (Joint STARS or JSTARS) ............... 4
Current E-8C Sustainment and Modernization Efforts ............................................................. 6
Prime Mission Equipment (PME) Diminishing Manufacturing Sources (DMS)................ 6
Kill Chain Enhancement Modifications .............................................................................. 7
Aircraft Spares and Repair Parts ......................................................................................... 8
JSTARS Modernization....................................................................................................... 8
Test and Infrastructure ......................................................................................................... 8
Previous E-8C Recapitalization Efforts ................................................................................... 10
E-10 Program .................................................................................................................... 10
Current E-8C Recapitalization Efforts..................................................................................... 14
E-3 Sentry (AWACS)............................................................................................................... 17
Current E-3 Sustainment and Modernization Efforts .............................................................. 18
Block 40/45 Upgrade (E-3G) ............................................................................................ 19
Next Generation Identification Friend or Foe (NGIFF) .................................................... 20
Training, Support, and Infrastructure (TSI) ...................................................................... 21
DMS Replacement of the Avionics for Global Operation and Navigation
(DRAGON) .................................................................................................................... 21
Electronic Protection (EP) ................................................................................................. 21
Internet Protocol Enabled Capability (IPEC) .................................................................... 21
Combat Identification (CID) Diminishing Manufacturing Sources .................................. 22
Air Education and Training Command (AETC) Maintenance Training Devices
(MTD) Upgrades – Field Training Detachments ........................................................... 22
Reliability, Maintainability, and Availability (RM&A) Modifications ............................. 22
Vertical Stabilizer and Rudder Modifications ................................................................... 22
Low Cost Modifications – Airframe ................................................................................. 22
Low Cost Modifications – Avionics & Mission Systems .................................................. 22
Aircraft Spares and Repair Parts ....................................................................................... 22
Command and Control, Intelligence, Surveillance, and Reconnaissance (C2ISR) ........... 23
Communications Network Upgrade .................................................................................. 23
Previous E-3 Recapitalization Efforts ..................................................................................... 26
E-10 Program .................................................................................................................... 26
Current E-3 Recapitalization Efforts ....................................................................................... 26
RC-135 Family of Aircraft ...................................................................................................... 26
RC-135V/W RIVET JOINT .............................................................................................. 27
RC-135U COMBAT SENT ............................................................................................... 28
RC-135S COBRA BALL .................................................................................................. 29
Current RC-135 Sustainment and Modernization Efforts ....................................................... 30
RIVET JOINT Baseline Modification............................................................................... 30
COMBAT SENT Baseline Modification ........................................................................... 31
COBRA BALL Baseline Modification ............................................................................. 31
Aircraft Spares and Repair Parts ....................................................................................... 31
Defense Airborne Recce Projects (DARP) RC-135 .......................................................... 31
Baseline Configuration Development ............................................................................... 31

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Airborne SIGINT Development - RC-135 RIVET JOINT ............................................... 32
Previous RC-135 Recapitalization Efforts............................................................................... 34
E-10 Program .................................................................................................................... 34
Current RC-135 Recapitalization Efforts ................................................................................ 34
WC-135 Constant Phoenix ...................................................................................................... 35
Current WC-135 Sustainment and Modernization Efforts ...................................................... 36
Current WC-135 Recapitalization Efforts ............................................................................... 36
OC-135B Open Skies .............................................................................................................. 37
Current OC-135B Sustainment and Modernization Efforts .................................................... 38
OC-135 Open Skies Sensors ............................................................................................. 38
Current OC-135B Recapitalization Efforts ............................................................................. 41
E-6B Mercury .......................................................................................................................... 41
Current E-6B Sustainment and Modernization Efforts ........................................................... 42
Safety Deficiencies............................................................................................................ 43
Tech Insertion .................................................................................................................... 43
Service Life Extension Program (SLEP)........................................................................... 43
Communications Upgrade ................................................................................................. 43
Block I ............................................................................................................................... 43
Multi-Role Tactical Common Data Link (MR-TCDL) ..................................................... 43
Auxiliary Power Unit (APU)............................................................................................. 44
Family of Advanced Beyond-Line-of-Sight Terminals/Presidential and National
Voice Conferencing (FAB-T/PNVC) ............................................................................. 44
Common Ground Equipment ............................................................................................ 44
Navy Strategic Communications Project .......................................................................... 44
Current E-6B Recapitalization Efforts..................................................................................... 46
Issues for Congress ........................................................................................................................ 46
Potential for Shortfall in C2ISR Capabilities .......................................................................... 46
DOD, Air Force, and Navy priorities ...................................................................................... 46
Will modernization efforts allow for delayed recapitalization efforts? ................................... 48
Remotely Piloted Aircraft Considerations ............................................................................... 48
Implications of Modernization and Recapitalization on Basing.............................................. 48
Industrial Base Concerns Associated with C2ISR Sustainment .............................................. 49
Conclusion ..................................................................................................................................... 49

Figures
Figure 1. E-8C Joint STARS............................................................................................................ 4
Figure 2. E-10A ............................................................................................................................. 10
Figure 3. E-3 Sentry (AWACS) ..................................................................................................... 17
Figure 4. RC-135V/W RIVET JOINT ........................................................................................... 27
Figure 5. RC-135U COMBAT SENT ............................................................................................ 28
Figure 6. RC-135S COBRA BALL ............................................................................................... 29
Figure 7. WC-135 Constant Phoenix ............................................................................................. 35
Figure 8. OC-135B Open Skies ..................................................................................................... 37
Figure 9. E-6B Mercury ................................................................................................................. 41

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Tables
Table 1. Current Boeing 707-Based DOD C2ISR Force ................................................................. 2
Table 2. Boeing 707-Based DOD C2ISR Force Aircraft Availability ............................................. 3
Table 3. Current E-8C Sustainment and Modernization Efforts ...................................................... 9
Table 4. Previous E-8C Recapitalization Efforts Under the E-10 Program ................................... 13
Table 5. Current E-8C Recapitalization Efforts ............................................................................. 16
Table 6. Current E-3 AWACS Sustainment and Modernization Efforts ........................................ 24
Table 7. Current RC-135 Sustainment and Modernization Efforts ................................................ 33
Table 8. Current OC-135B Sustainment and Modernization Efforts ............................................. 40
Table 9. Current E-6B Sustainment and Modernization Efforts .................................................... 45

Appendixes
Appendix. Legislative Activity ...................................................................................................... 50

Contacts
Author Contact Information........................................................................................................... 51

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Introduction
The fleet of manned aircraft that accomplishes the Department of Defense’s (DOD’s) Command
and Control (C2) and Intelligence, Surveillance, and Reconnaissance (ISR) missions for the joint
military community (E-8, E-3, RC-135, WC-135, OC-135, and E-6) is primarily based on Boeing
707 aircraft procured from the 1960s to the early 1990s. As the age of these legacy C2ISR aircraft
increases, understanding the Air Force and Navy modernization and recapitalization plans is
likely important for Congress. The central issue addressed in this report is the benefits and
drawbacks of continued sustainment and modernization of these aircraft compared to funding for
recapitalization and transfer of these missions to new aircraft. This report examines the Air
Force’s and Navy’s current sustainment, modernization, and recapitalization efforts for these
Boeing 707-based aircraft.
Without sufficient sustainment and modernization funding, many analysts argue the legacy
C2ISR fleet is likely to become a decrepit force ill-suited to the potential challenges posed by
future adversaries. The physical wear-and-tear on these aircraft from the demands of their already
lengthy service lives leads aging airframe structures to need reinforcement, engines to require
maintenance, and computer and electronic components to face obsolescence. Even if corrosion,
metal fatigue, and parts obsolescence do not take their toll on the fleet, military analysts point out
that potential adversaries are acquiring advanced, anti-access/area-denial (A2/AD) weapon
systems that would make it harder for the legacy C2ISR aircraft to get close to the battle.
This report addresses potential congressional oversight and appropriations concerns for the
sustainment, modernization, and recapitalization of the DOD’s Boeing 707-based legacy C2ISR
aircraft fleet. It does not address options for recapitalization currently being offered by industry to
other countries. Congress has the authority to approve, reject, or modify Air Force and Navy
funding requests for C2ISR aircraft sustainment, modernization, and recapitalization, as well as
maintain oversight of the nation’s C2ISR requirements and capabilities. Congress’s decisions on
appropriations for the C2ISR force could impact the nation’s C2ISR capabilities and have
additional consequences for the U.S. aerospace industry.
A key issue for Congress is whether to continue providing sustainment, modernization, and/or
recapitalization funding for DOD’s Boeing 707-based legacy C2ISR aircraft fleet, and if so, at
what levels. Pertinent to the discussion is the potential for a shortfall in the nation’s C2ISR
capabilities if Congress or DOD chooses to minimize funding for sustainment and upgrades that
would keep the weapon systems viable until they are recapitalized. Another issue for Congress is
DOD, Air Force, and Navy priorities for sustainment, modernization, and recapitalization efforts.
An important question is whether development of a C2ISR replacement aircraft can or should be
further delayed by increasing funding for legacy C2ISR aircraft sustainment and modernization.
Additionally, potentially shifting some of the legacy C2ISR missions to remotely piloted aircraft
may affect recapitalization efforts. Congress’s decisions on these issues could also have
implications for any potential future base realignment and closure (BRAC) decisions as well as
impact the U.S. aircraft manufacturing industrial base. Ultimately, the priority the DOD places on
legacy C2ISR sustainment, modernization, and recapitalization, and any decisions considered by
Congress, could have potential consequences for future national defense strategies and on U.S.
C2ISR capabilities, given the pivotal role C2ISR plays in implementing those strategies.

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A note on sources: As small fleets of specialized aircraft, relatively little has been written on the
programs discussed in this paper. Description of each therefore relies on Air Force fact sheets,
which are used to introduce each aircraft before discussing the supporting budget items.

Background
Dash 80/Boeing 7071
In 1952, the Boeing Company2 began development of the Model 367-80 prototype aircraft,
known as “Dash 80.” That prototype led to the military KC-135 tanker and the commercial 707
aircraft, which shared the basic design of the Dash 80 but were very different airplanes, neither
being a derivative of the other.3 A total of 820 C/KC-135s were built through 1966, 732 as tankers
and 88 modified for special purposes, including cargo carriers, reconnaissance airplanes, Strategic
Air Command airborne command posts, and transports for high-ranking government officials.
Boeing delivered 856 Model 707s between 1957 and 1994, with 725 delivered between 1957 and
1978 for commercial use. Most civil 707s left in service after 2007 were converted to freighters,
while a number were used as corporate transports.

Current Boeing 707-Based DOD C2ISR Force
The Department of Defense’s current C2ISR aircraft fleet based on the Boeing 707 includes 89
operational aircraft. Table 1 lists the types of aircraft and their average age. Additional
information on each aircraft type, the current sustainment and modernization efforts, previous
recapitalization efforts (if applicable), and current recapitalization efforts follows the table.
Table 1. Current Boeing 707-Based DOD C2ISR Force
U.S. Air Force Aircraft
E-8C JSTARS
E-3 Sentry (B/C/G)
RC-135V/W RIVET JOINT (V/W)
RC-135U COMBAT SENT
RC-135S COBRA BALL
WC-135 Constant Phoenix (C/W)
OC-135B Open Skies
E-6B Mercury

Number of Operational
Aircraft in Inventory
16a
20/5/6
8/9c
2
3
1/1
2
16

Average Age (in
years)
13.6b
36.1/31.5/33.2
49.8/51.8
49.5
52.3
50.2/52.3
52.3
21d

Source: “Aircraft Assets & Availability,” Air Force Times, October 20, 2014, p. 19; “2014 Air Force Almanac,” Air
Force Magazine, May 2014, pp. 77-81; Justification books for Air Force procurement accounts and research,

1
For more information, see Boeing KC-135 Stratotanker Historical Snapshot, accessed May 13, 2015, at
http://www.boeing.com/history/products/kc-135-stratotanker.page; Boeing 707/720 Commercial Transport Historical
Snapshot, accessed May 13, 2015, at http://www.boeing.com/history/products/707.page; and “Boeing Marks 50th
Anniversary of 707 First Flight,” accessed May 13, 2015, at http://boeing.mediaroom.com/2007-12-20-Boeing-Marks50th-Anniversary-of-707-First-Flight.
2
Now Boeing Commercial Airplanes.
3
For simplicity, in this report the term “Boeing 707” is used to refer to both derivatives of the Dash 80.

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development, test, and evaluation accounts for FY2016 and prior years; and Justification books for Navy
procurement accounts and research, development, test, and evaluation accounts for FY2016 and prior years.
a.

The E-8C inventory also includes one pilot trainer aircraft, which does not carry the standard mission
equipment, and one test aircraft.

b.

This age is based on when the aircraft became E-8C JSTARS aircraft, not when they were originally
manufactured by Boeing as 707-300s in the 1960s.

c.

In addition, there are three TC-135W aircraft used for training (average age of 52.1 years) and one NC135W aircraft used for testing (52.3 years old).

d.

CRS calculation based on delivery schedule of aircraft.

Despite the advanced age of the Boeing 707-based DOD C2ISR aircraft fleet, aircraft availability
remain at levels sufficient to sustain current operational requirements. Table 2 lists the percentage
of time aircraft were available, known as mission-capable rates, for the past five years.
Table 2. Boeing 707-Based DOD C2ISR Force Aircraft Availability
Percentage of time aircraft were available (mission-capable rates)
U.S. Air Force
Aircraft

2010

2011

2012

2013

2014

E-8C

81.1

77.3

78

73.6

72.1

E-3B

71.2

70.1

72.5

75.2

76.5

E-3C

72.7

74.0

73.3

78.4

76.6

E-3G

N/A

N/A

85.4

88.4

83.4

RC-135V

79.1

77.7

75.0

75.3

75.2

RC-135W

79.6

77.4

79.8

80.0

70.9

RC-135U

81.9

86.5

83.6

85.8

79.6

RC-135S

88.9

83.9

86.5

72.4

81.9

WC-135C

74.0

58.4

85.6

80.5

75.8

WC-135W

74.8

63.1

55.7

82.4

59.8

OC-135B

72.6

64.6

79.9

75.7

77.9

2010

2011

2012

2013

2014

—

—

—

—

—

U.S. Navy
Aircraft
E-6B

Source: “Aircraft Assets & Availability,” Air Force Times, October 20, 2014, p. 19.
Notes: Data for the E-6B is unavailable.

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E-8C Joint Surveillance Targeting Attack Radar System (Joint
STARS or JSTARS)
Figure 1. E-8C Joint STARS

Source: U.S. Air Force official website, E-8C Joint STARS Factsheet, March 31, 2005, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104507/e-8c-joint-stars.aspx.

The E-8C JSTARS is an airborne battle management, command and control, intelligence,
surveillance, and reconnaissance platform. Its primary mission is to provide theater ground and
air commanders with ground surveillance to support targeting and attack operations.
The E-8C is a modified Boeing 707-320 commercial airframe extensively remanufactured and
modified with radar, communications, operations, and control subsystems required to perform its
mission. The most prominent external feature is a 27-foot long, canoe-shaped radome under the
forward fuselage that houses a 24-foot long, side-looking phased array antenna. The antenna can
tilt to either side of the aircraft where it can develop a 120-degree field of view covering nearly
19,305 square miles, and is capable of detecting targets more than 155 miles away. (In short, the
JSTARS’ sensors detect and monitor vehicles and other ground-based objects over an area
roughly twice the size of New Jersey.) The radar also has limited capability to detect helicopters,
rotating antennas, and low, slow moving fixed wing aircraft. The information is relayed in near
real time to ground command, control, communications, computers, and intelligence nodes.4
The JSTARS concept evolved from U.S. Army and Air Force programs to develop, detect, locate,
and attack enemy armor at ranges beyond the forward area of troops.5 The ability of airborne
side-looking radar to detect slow-moving and fixed targets on the ground was demonstrated in the

4

U.S. Air Force E-8C Fact Sheet, March 31, 2005, at http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/
Article/104507/e-8c-joint-stars.aspx.
5
Ibid.

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Air Force’s Pave Mover program in 1982.6 JSTARS combines technologies developed in Pave
Mover and the Army’s Stand-Off Target Acquisition System program.7
A developmental contract for the E-8 JSTARS was awarded to Grumman Corporation in
September 1985. Original plans called for 10 conversion aircraft. The plan later changed to 22
newly-built aircraft and subsequently changed again to 20 aircraft before a final total of 17
operational aircraft emerged. The production E-8s were originally planned to be new aircraft
based on the U.S. Navy’s E-6 Hermes aircraft (a Boeing 707-320 aircraft with more powerful
engines), however, in October 1989 Boeing announced the end of production of the 707 airframe
upon completion of British and French airborne warning and control system aircraft in 1991. As a
result, the E-8C aircraft are retrofitted Boeing 707 aircraft acquired from other sources. The first
two test aircraft were former Boeing 707-328 commercial airliners from American Airlines and
Qantas Airlines. The first E-8C entered operational service in late 1995.8
The E-8C aircraft fleet averages 13.6 years of age.9 This is based on when the aircraft became E8C JSTARS aircraft, not when they were originally manufactured by Boeing as 707-300s in the
1960s.10
The 116th Air Control Wing, a Georgia Air National Guard unit, and the 461st Air Control Wing,
an associate active-duty Air Combat Command unit, operate 1611 operational12 E-3C JSTARS at
Robins Air Force Base, Georgia.13

6
“Joint USAF/Army JSTARS System Set for Airborne Test in 1988,” Aviation Week & Space Technology, December
9, 1985, p. 91.
7
“E-8 J-STARS,” Military Periscope, accessed September 23, 2014, at https://www.militaryperiscope.com/weapons/
aircraft/p-r-e/w0003128.html.
8
“E-8 J-STARS,” Military Periscope, accessed September 23, 2014, at https://www.militaryperiscope.com/weapons/
aircraft/p-r-e/w0003128.html.
9
“Aircraft Assets & Availability,” Air Force Times, October 20, 2014, p. 19.
10
Air Force budget overview documents, justification books for Air Force procurement accounts, and justification
books for Air Force research, development, test, and evaluation accounts for FY2016 and prior years.
11
One operational E-8C was retired in FY2013 due to being damaged beyond economical repair in an air refueling
incident on March 13, 2009, reducing the operational inventory from 17 to 16 aircraft. For more information, see Air
Combat Command Press Release, “E-8C Accident Report Released,” July 9, 2009, at http://www.acc.af.mil/news/
story.asp?id=123158008, and Secretary Michael Donley and General Norton Schwartz, USAF Force Structure
Changes: Sustaining Readiness and Modernizing the Total Force white paper, February 2013.
12
The Air Force E-8C inventory also includes one pilot trainer aircraft, which does not carry the standard mission
equipment, and one test aircraft, T-3.
13
On October 1, 2002, the Air Force redesignated the 116th Bomb Wing, a Georgia Air National Guard unit, as the
116th Air Control Wing while simultaneously deactivating the 93rd Air Control Wing, an active-duty Air Combat
Command unit. The new 116th Air Control Wing was the first organization to activate under the Air Force’s Total
Force Initiative as a “blended” wing blending Guard and active-duty Airmen into a single unit. On October 1, 2011, the
blended wing changed to an Active-Associate construct. The newly activated 461st Air Control Wing assumed
administrative oversight of active duty personnel from the 116th Air Control Wing. According to the Air Force, the
change was primarily for administrative reasons as updated Air Force regulations did not cover a blended unit, and led
to issues with the handling of promotions, disciplinary actions, and other administrative issues. For additional
information see U.S. Air Force E-8C Fact Sheet, March 31, 2005, at http://www.af.mil/AboutUs/FactSheets/Display/
tabid/224/Article/104507/e-8c-joint-stars.aspx and Wayne Crenshaw, “116th’s Blended Unit to Be Split Again Friday,”
The Telegraph, September 30, 2011, at http://www.macon.com/2011/09/30/1725024/changes-for-116th-aircontrol.html.

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Current E-8C Sustainment and Modernization Efforts14
With the Air Force’s decision to recapitalize the E-8C JSTARS fleet beginning in FY2015, the
Administration’s FY2015 budget request did not include modernization funding for the E-8C
JSTARS. To fund E-8C JSTARS recapitalization, the Air Force planned (as part of the FY2015
Budget Request) to divest the E-8C test capability, including the T-3 test aircraft, and begin the
retirement of five operational E-8C JSTARS aircraft. As part of the National Defense
Authorization Act for FY2015, Congress prohibited the Air Force from taking any action to retire
or to prepare to retire operational JSTARS aircraft until 30 days after the Secretary of the Air
Force submits a report to the congressional defense committees providing an update of the results
of the analysis of alternatives for recapitalizing the JSTARS capability and an assessment of the
cost and schedule of developing and fielding a new aircraft and radar system to replace the
current JSTARS aircraft.15 The Administration’s FY2016 budget request delays the divestiture of
five operational E-8C JSTARS aircraft from FY2016 to FY2019 and restores funding to complete
one modernization program for those five operational aircraft that was in progress for the other 11
operational aircraft prior to FY2015.
The following E-8C sustainment and modernization initiatives, currently in the program of
record, are either recently completed or currently in progress. Additional information on each
effort is detailed in the following sections.
•

Prime Mission Equipment (PME) Diminishing Manufacturing Sources (DMS);

•

Kill Chain Enhancement Modifications;

•

JSTARS Modernization; and

•

Test and Infrastructure.

•

It may be noteworthy that none of these programs deals with the E-8C engine or
airframe.

Prime Mission Equipment (PME) Diminishing Manufacturing Sources (DMS)
The Air Force considers the Prime Mission Equipment (PME) Diminishing Manufacturing
Sources (DMS) program a top issue for fleet viability. Parts obsolescence stemming from an
overdue technology refresh requires a major modification to maintain the existing processing
capabilities and specification compliance. PME is required for JSTARS to maintain net-centric
war fighter capabilities – Ground Moving Target Indicator (GMTI) and Battle Management
Command and Control (BMC2). The last major modification to the mission computing hardware
took place during the Computer Replacement Program (CRP) from 1997-2005. The modification
addresses hardware and software DMS issues and commercial-of-the-shelf technology refresh for
the Operator Work Station, the Central Computing subsystem, and the Radar Airborne Signal
Processor subsystem. Modifications also include mission and maintenance crew trainers, software
maintenance, and support systems at Robins AFB, Georgia.
14
Information for current E-8C sustainment and modernization efforts derived from Air Force budget overview
documents, justification books for Air Force procurement accounts, and justification books for Air Force research,
development, test, and evaluation accounts for FY2016 and prior years unless noted. Previous modernization efforts are
not included in this report.
15
P.L. 113-291, Section 219. See the Appendix for full text.

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In October 2013, the Air Force awarded a contract for seven modernization kits for the PMEDMS program.16 Two of the seven kits were procured with $5.85 million of National Guard and
Reserve Equipment Appropriation funding.17 The remaining five kits were procured with JSTARS
funding. In September 2014, the contract was amended to add four additional kits for a total of 11
overall. Beginning in FY2016, the Air Force plans to award the contract for the remaining five
JSTARS aircraft to complete the fleet retrofit of 16 aircraft. Funding lapsed in FY2015 because
the Air Force planned to end JSTARS modernization efforts to focus funding on recapitalization
efforts. Funding was restored for FY2016 through FY2018 to complete the modification to the
entire fleet.18

Kill Chain Enhancement Modifications
The JSTARS Kill Chain Enhancement program monitors, identifies, evaluates, compares and
prioritizes projects that expediently deliver warfighting capabilities. The program focused on
rapid implementation and delivery, rather than long-term production. The Air Force implemented
emerging technologies that greatly increase system and system-of-systems capability, as well as
interoperability with joint service, allied, and coalition systems. Representative efforts include
imagery comparison, Remotely Piloted Aircraft (RPA) data integration, Broadcast Intel track
correlation, multi-sensor radar service and tracker improvements, time critical targeting
initiatives, Internet Protocol enabling technologies to enhance command and control to shorten
the kill chain, machine-to-machine data exchange, enhanced targeting and interdiction, radar &
Synthetic Aperture Radar (SAR) enhancements.
Project candidates under this program typically arise out of warfighter experiments, exercises,
analysis of operational data, or real world lessons learned. Priority is based on immediate benefit
to the warfighter, technical feasibility, and overall executability.
The operational and trainer aircraft were modified with procurement funds, while the test aircraft
(T-3) was modified with RDT&E funds.

16

A complete “kit” actually includes two different kits (a Group A kit and a Group B kit). The kits referred to in this
section treat one A kit and one B kit together as one kit.
17
Congress established the National Guard and Reserve Equipment Appropriation (NGREA) in 1981 to provide the
equipment necessary to maintain the readiness of National Guard and Reserve components. NGREA funding is
intended to supplement the services’ base procurement appropriations, not substitute for it. The Active Components are
still expected and required to fund and equip their respective Guard and Reserve components to ensure reserve units are
at a high level of readiness should they need to be deployed. The Chiefs of the National Guard and Reserve
components enhance readiness by procuring items that the services’ base appropriations do not fund. NGREA funds are
used to procure new aircraft; major weapon systems that are already established as a stable procurement program;
equipment support items; and modifications to rebuild, overhaul, or refurbish existing items without expanding on the
platform capability currently supported by the Active components. NGREA provides the needed flexibility to the
Chiefs of the National Guard and Reserve components to procure priority readiness items subject only to the authority,
direction, and control of the Secretary of Defense. (Source: U.S. Congress, Senate Committee on Appropriations,
Department of Defense Appropriations Bill, 2014, Report to accompany S. 1429, 113th Cong., 1st sess., August 1, 2013,
S.Rept. 113-85, pp. 142-143.)
18
The pilot trainer aircraft does not carry the standard mission equipment, so it does not require this modification. The
test aircraft, T-3, was previously modified with RDT&E funds.

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U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Aircraft Spares and Repair Parts
This program provides funding for repair parts for the E-8.

JSTARS Modernization
This development program encompassed multiple efforts to develop and integrate system
improvements across the E-8C platform. Program accomplishments in the last year of funding in
FY2014 consisted of multiple efforts to develop and integrate platform wide system
improvements such as Multi-Agency Communication Capability, CENTRIX, Ground Moving
Target Indicator Risk Reduction and Beyond-Line-of-Sight Network Architecture Upgrades.
Additionally, training and support systems upgrade efforts included Weapon Systems Trainer,
Navigator Training System, and Mission Crew Trainers to include a Mission Maintenance
Trainer, Prime Mission Equipment-Maintenance Training Device (PME-MTD) and the Mission
System Trainer.

Test and Infrastructure
The test infrastructure program included the JSTARS Extended Test Support (JETS), JSTARS
Test Force (JTF), and C2 Enterprise Integration Facility. All JSTARS efforts relied on the
components of this test infrastructure to carry out RDT&E activities. The infrastructure included
a T-3 test aircraft, laboratories, support facilities, security, information assurance, and range
support. All of the developmental programs have been completed. In FY2014, the program began
the transfer of test infrastructure assets to Robins AFB, GA. The JETS contract and JTF lease was
extended into the second quarter FY2015 to facilitate preparation of the T-3 aircraft for retirement
and the disposition of residual Government Furnished Equipment.
Table 3 is the FY2016 budget submission for E-8C procurement and E-8C research,
development, test, and evaluation programs derived from Air Force budget justification books. It
summarizes prior-year and estimated future-year expenditures for E-8C sustainment and
modernization programs that either recently completed or are currently in progress.

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Table 3. Current E-8C Sustainment and Modernization Efforts
(in millions of dollars)
Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total
Cost

Prime Mission Equipment (PME) Diminishing Manufacturing
Sources (DMS)

49.716

55.967

—

18.001

6.300

10.800

—

—

—

140.784

Kill Chain Enhancement
Modifications

112.106

0.011

—

—

—

—

—

—

—

112.117

Aircraft Spares and Repair Parts

—

0.523

—

—

—

—

—

—

—

0.523

Total Procurement Items

161.822

56.501

—

18.001

6.300

10.800

—

—

—

253.424

RDT&E Items

Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total
Cost

JSTARS Modernization

—

10.050

—

—

—

—

—

—

—

27.308

Test and Infrastructure

—

17.258

—

—

—

—

—

—

—

17.258

—

27.308

—

—

—

—

—

—

—

27.308

Procurement Items

Total RDT&E Items

Source: Prepared by CRS based on justification books for Air Force procurement accounts and Air Force research, development, test, and evaluation accounts for
FY2016 and prior years.

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Previous E-8C Recapitalization Efforts19
E-10 Program
Figure 2. E-10A

Source: Boeing File Photo, http://www.boeing.com/news/frontiers/archive/2004/july/photos/july_i_ids2.jpg.

Initially, the E-10A was intended to replace the E-8C JSTARS aircraft to provide improved
tracking of moving ground targets. Additionally, it was designed to detect low-flying cruise
missiles. Later derivatives of the E-10A were intended to replace the E-3 Sentry AWACS airborne
surveillance aircraft (E-10B) and RC-135 RIVET JOINT signals intelligence aircraft (E-10C).20
In FY2003, the Air Force established the Multi-sensor Command and Control Constellation
(MC2C) program. The MC2C was a horizontally integrated architecture of command and control
and intelligence, surveillance, and reconnaissance capabilities. The MC2C was a key enabler for
the effects-based capabilities needed to achieve Global Strike Task Force objectives. The MC2C
Program contained two separate projects – the airframe and the sensors. The MC2C program
absorbed and continued the Multi-Platform Radar Technology Insertion Program (MP-RTIP)
radar effort that was previously reported in the Joint STARS program.21 MC2C transitioned the
707-based MP-RTIP radar to a 767-based MP-RTIP radar with funding from the Joint STARS
program.
19

Information for previous recapitalization efforts derived from justification books for Air Force research,
development, test, and evaluation accounts for FY2010 and prior years unless noted.
20
Diane Stratman, “Eyes and Ears Above,” Boeing Frontiers, July 2004, at http://www.boeing.com/news/frontiers/
archive/2004/july/i_ids2.html.
21
The MP-RTIP project was the result of a restructuring of the Joint STARS Radar Technology Insertion Program
(RTIP), a formerly pre-planned product improvement for the Joint STARS. The RTIP effort began in FY1998 and was
restructured into the MP-RTIP project in FY2002 to better track program funding.

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In FY2005, the MC2C program was renamed Command and Control (C2) Constellation and the
airframe and sensor projects were transferred to a new program, the Multi-sensor Command and
Control Aircraft (MC2A.)22 In FY2006, the MC2A Program was renamed E-10 Squadrons to
directly associate the approved Mission Data Series designation for the MC2A. The airframe and
sensors projects remained in the new E-10 Squadrons Program.
The E-10 was intended to be a key C2 Constellation node bringing operational command and
control through the use of advanced sensors, sensor fusion, high-speed, wide-band
communications systems, and battle management integration software to enable detection,
designation, and prosecution of time critical targets. The E-10 also would have interfaced with
multi-Service ground/air/space-based sensors, intelligence and communications assets to shorten
the decision cycle for combat operations. In short, the E-10 would have added interoperability
and capability beyond the existing JSTARS platform, with an especial emphasis on speed. The
result, according to the Air Force, would have been weapons-quality target cueing for joint and
coalition shooters to engage time sensitive cruise missiles and other fleeting high-priority targets.
The E-10’s Multi-Platform Radar Technology Insertion Program (MP-RTIP) radar would have
addressed targets the E-8 could not, with Air Moving Target Indicator (AMTI) capability for
cruise missile defense. Next-generation Ground Moving Target Indicator (GMTI) and Synthetic
Aperture Radar (SAR) imaging for improved surface surveillance would have improved on E-8
capabilities. An open system architecture to facilitate dynamic Battle Management, Command &
Control (BMC2) gave the E-10 growth potential for remotely piloted aircraft control, space radar
interface and ISR management functions. The Air Force envisioned future E-10 increments would
incorporate advanced sensors for air surveillance operations.
The E-10 program, as well as the E-10 portion of the MP-RTIP radar development, was
terminated in FY2008.23 According to the Air Force, the E-10 was canceled because of cost
growth with the program.24 Others believe the complexity of the E-10 program made it
controversial and led to the cancellation. Additionally, according to some views, policymakers
differed on the future of the ISR mission itself. Some people believed the mission could be
accomplished by space-based assets, while others viewed unmanned aircraft as most cost
effective, while others believed in downgrading with role of high-cost platforms in favor of
networked, distributed collection systems.25

22

The new C2 Constellation program absorbed Horizontal Integration efforts and Joint Expeditionary Force
Experiments to support Horizontal Integration efforts. The aperture of the program expanded beyond the previous
MC2C focus, no longer being solely tied to what would become the E-10.
23
The E-10A Program was terminated in February 2007 with amended termination direction in May 2007 that
authorized a limited risk reduction of Battle Management Command and Control (BMC2) Mission Execution, BMC2
Kill Chain, and Wide Area Surveillance (WAS) Radar Hardware verification. Funding for these efforts beyond FY2008
was provided in other program elements not associated with the E-10 Project. Additionally, the smaller version of the
MP-RTIP program continued to be developed to provide a radar for the MQ-4 Global Hawk Block 40 configuration. In
FY2009, the E-10 Squadrons Sensors project transferred to the Global Hawk program element.
24
Testimony of Gen Michael Moseley, Air Force Chief of Staff, to U.S. Congress, Senate Committee on Armed
Services, Department of the Air Force in review of the Defense Authorization Request for Fiscal Year 2009 and the
Future Years Defense Program, 110th Cong., 2nd sess., March 5, 2008.
25
Loren B. Thompson, U.S. Air Dominance in a Fiscally Constrained Environment: Defining Paths to the Future Intelligence, Surveillance and Reconnaissance, Lexington Institute, March 2013, p. 10, at http://lexingtoninstitute.org/
wpcontent/uploads/2013/09/AirDominance-ISR.pdf.

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Table 4 summarizes previous expenditures for the E-8C recapitalization efforts under the E-10
and related programs as reported in justification books for Air Force research, development, test,
and evaluation programs.

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Table 4. Previous E-8C Recapitalization Efforts Under the E-10 Program
(in millions of dollars)
Total
Cost
FY1998

Total
Cost
FY1999

Total
Cost
FY2000

Total
Cost
FY2001

Total
Cost
FY2002

Total
Cost
FY2003a

Total
Cost
FY2004

Total
Cost
FY2005

Total
Cost
FY2006

Total
Cost
FY2007

Total
Cost
FY2008

Total Cost

Radar Technology Insertion Program
(RTIP)b

0.005

0.017

0.063

0.050

—

—

—

—

—

—

—

0.135

Multi-Platform – Radar Technology
Insertion Program (MP-RTIP)c

—

—

—

—

0.073

—

—

—

—

—

—

0.073

Multi-Sensor Command and Control
Constellation (MC2C) – Airframe

—

—

—

—

—

129.395

209.747

—

—

—

—

339.142

Multi-Sensor Command and Control
Constellation (MC2C) – Sensors

—

—

—

—

—

208.369

145.586

—

—

—

—

353.955

Multi-Sensor Command and Control
Aircraft (MC2A) – Airframe

—

—

—

—

—

—

—

198.394

—

—

—

198.394

Multi-Sensor Command and Control
Aircraft (MC2A) – Sensors

—

—

—

—

—

—

—

192.563

—

—

—

192.563

E-10 Squadrons – Airframe

—

—

—

—

—

—

—

—

247.140

169.629

0.368

417.137

E-10 Squadrons – Sensors

—

—

—

—

—

—

—

—

131.731

182.295

37.307

351.333

0.005

0.017

0.063

0.050

0.073

337.764

355.333

390.957

378.871

351.924

37.675

1,852.732

RDT&E Items

Total RDT&E Items

Source: Prepared by CRS based on justification books for Air Force research, development, test, and evaluation accounts for FY2010 and prior years.
a.

MC2C received $147M in FY2003 Defense Emergency Response Fund (DERF) funding which is included in the above table as follows: $64.8M to MC2C-Airframe,
$61.7M to MC2C-Sensors, and $20.5M for MC2C horizontal integration efforts (accounted for in MC2C-Airframe, in addition to the $64.8M).

b.

Funding for this effort was contained in the Joint STARS program element, not as a separate program element or project.

c.

MP-RTIP became a separate project in FY2002, but funding remained in the Joint STARS program element until FY2003.

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Current E-8C Recapitalization Efforts26
The Air Force began the current JSTARS Recapitalization27 effort in FY2015.28 JSTARS Recap is
a manned aircraft replacement for the legacy E-8C.
JSTARS Recap is designed to integrate
Industry Options for JSTARS Recap
current and mature sub-system
Although the Acquisition Decision Memorandum is awaiting
technologies onto a commercially
final approval, press reports indicate industry vendors have
available business class jet to provide
identified their preliminary plans for competing for the
tactical Battle Management, Command
JSTARS Recap program. Boeing, Bombardier, Gulfstream, and
and Control (BMC2) and Battlespace
Northrup Grumman are all expected to compete. Boeing
Awareness (BA) across the full range of
plans to offer the 737-700 Boeing Business Jet (BBJ). Boeing
previously looked at an offering based on the Navy’s P-8A
military operations. An on-board crew,
Poseidon which uses the longer Boeing 737-800, but appears
powerful radar, and robust
to have opted for the lighter BBJ aircraft. Bombardier will
communications and information systems
likely offer its Global 6000, a long-range business jet.
would enable theater ground and air
Gulfstream will likely offer the G650, a twin-engine business
commanders to make quick decisions
jet. Northrup Grumman, which is not an aircraft
manufacturer, appears to be testing a G550 aircraft.29
during complex and rapidly unfolding
operations. JSTARS Recap aims to enable
rapid decisions by using advanced battle management aids and information fusion technologies to
automate tracking and addressing time-critical targets. JSTARS Recap is intended to address the
sustainment challenges in the aging E-8C fleet while focusing on known mission area gaps.

26

Information for current E-8C recapitalization efforts derived from Air Force budget overview documents,
justification books for Air Force procurement accounts, and justification books for Air Force research, development,
test, and evaluation accounts for FY2016 and prior years unless noted.
27
The current JSTARS Recapitalization effort is shortened to “JSTARS Recap” in Air Force budget documents. The
shortened name is used in this report when referring to the current recapitalization effort. “JSTARS Recapitalization” is
used in this report when referring to overall recapitalization efforts over the years.
28
The Air Force completed an Analysis of Alternatives (AOA) for JSTARS Recapitalization in 2011, which concluded
the optimum choice for the future was to use a business jet class aircraft with an advanced radar and on-board BMC2
suite. The AOA also concluded upgrading the current E-8C fleet with an advanced radar and new BMC2 Suite would
be the next best solution, but has significantly higher lifecycle costs. In testimony before the Senate Armed Services
Committee in March 2012, then-Air Force Chief of Staff General Norton Schwartz testified there was not enough
budget space to undertake a new start ISR platform. In testimony before the House Armed Services Committee in
March 2014, Air Force Chief of Staff General Mark Welsh testified the current Air Force proposal to recapitalize the
JSTARS is by downsizing capability in the current JSTARS program to provide the money to start a recapitalization
effort. (Sources: Written statement of Lt Gen Burton M. Field, Deputy Chief of Staff for Operations, Plans, and
Requirements and Lt Gen Charles R. Davis, Military Deputy, Office of the Assistant Secretary of the Air Force for
Acquisition, to U.S. Congress, House Committee on Armed Services, Subcommittee on Tactical Air and Land Forces,
Fiscal Year 2014 Department of Defense Combat Aviation Programs, 113th Cong., 1st sess., April 17, 2013; testimony
of Gen Norton Schwartz, Air Force Chief of Staff, to U.S. Congress, Senate Committee on Armed Services,
Department of the Air Force in review of the Defense Authorization Request for Fiscal Year 2013 and the Future Years
Defense Program, 112th Cong., 2nd sess., March 20, 2012; and testimony of Gen Mark Welsh, Air Force Chief of Staff,
to U.S. Congress, House Committee on Armed Services, Fiscal Year 2015 National Defense Authorization Budget
Request from the Department of the Air Force, 113th Cong., 2nd sess., March 14, 2014.)
29
Bill Sweetman, “Weight Saving Key to Boeing Joint STARS Platform Choice,” Aerospace Daily & Defense Report,
September 18, 2014, p. 2 and Kris Osborn, “Air Force Works to Replace JSTARS Fleet,” DOD Buzz.com, October 3,
2014, at http://www.dodbuzz.com/2014/10/03/air-force-works-to-replace-jstar-fleet/.

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The JSTARS Recap system is designed for day and night worldwide deployment in all weather
conditions. The Air Force’s intent is to relatively quickly field an initial capability that provides
an equivalent to the E-8C JSTARS, not to make the replacement fundamentally different or
significantly better in performance,30 and upgrade the capability in the future.
The JSTARS Recap program consists of multiple efforts culminating in the integration of four
major subsystems: BMC2, Sensor, Air Vehicle, and Communications. The Air Force has
developed an open source reference architecture to integrate these subsystems, which can be
competed separately. The Air Force hopes this approach will bolster competition, improving
affordability and reducing overall weapons system life-cycle costs. Such an architecture should
also allow the system to be adaptable and flexible to meet changing threats.
Currently a pre-Major Defense Acquisition
Remotely Piloted Aircraft Considerations
Program, JSTARS Recap is expected to
While the U.S. Air Force’s Analysis of Alternatives for JSTARS
undergo a Milestone A review in the third
Recapitalization from 2011 concluded the optimum choice for
quarter of FY2015 to determine whether to
the future was to use a business jet class aircraft, some
advance to a technology maturation and risk
analysts believe increases in technology allow for more
reduction phase and, if so, a Milestone B in
consideration of the use of remotely piloted aircraft or
autonomous systems in accomplishing more of the missions
the fourth quarter of FY2017 to decide
currently accomplished by manned aircraft.31 The DOD has
whether to proceed to engineering and
identified that “[remotely piloted] systems open up new
manufacturing development. The program is
avenues for pursuing systems that are smaller, lighter, faster,
to determine if the use of incentives for the
and more maneuverable and that take more risk than
EMD contract are appropriate for both the
equivalent manned platforms.”32 Additionally, great strides in
autonomy, teaming, multi-platform control, tipping, and cueing
delivery of test aircraft and
have reduced the number of personnel required to operate
modified/certified test aircraft. Post a
and maintain the remotely piloted systems, but more work
successful Milestone C, the program is to
remains.33 “Research and development in automation is
follow with a Low Rate Initial Production
advancing from a state of automatic systems requiring human
control toward a state of autonomous systems able to make
(LRIP) contract award, procuring 3 aircraft
decisions and react without human interaction.”34
aimed at achieving initial operational
capability in the fourth quarter of FY2023.
The remaining 12 aircraft would be procured in full rate production to support a full operational
capability in the fourth quarter of FY2026.
Table 5 is the FY2016 budget submission for JSTARS Recap procurement and JSTARS Recap
research, development, test, and evaluation programs derived from Air Force budget justification
books. It summarizes current and estimated future-year expenditures for JSTARS Recap
programs.

30
According to Col Henry Cyr, Commander of the 461st Air Control Wing, Robins AFB, GA as quoted by Kris
Osborn, “Air Force Works to Replace JSTARS Fleet,” DOD Buzz.com, October 3, 2014, at http://www.dodbuzz.com/
2014/10/03/air-force-works-to-replace-jstar-fleet/.
31
For a detailed discussion on DOD remotely piloted aircraft see CRS Report R42136, U.S. Unmanned Aerial Systems,
by (name redacted), and for a detailed discussion of the technological capabilities of autonomous systems see P.W.
Singer, Wired for War: The Robotics Revolution and Conflict in the 21st Century (New York: Penguin Books, 2009).
32
Department of Defense, Unmanned Systems Integrated Roadmap, FY2013-2038, Publication Reference Number 14S-0553, p. 18.
33
Ibid, p. 25.
34
Ibid, p. 72.

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Table 5. Current E-8C Recapitalization Efforts
(in millions of dollars)
Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total Cost

—

—

—

—

—

0.214

268.277

537.000

4,039.259

4,844.750

Total Procurement Items

—

—

—

—

—

0.214

268.277

537.000

4,039.259

4,844.750

RDT&E Items

Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total Cost

Technology Maturation and Risk
Reduction (Product
Development)

—

—

53.085

21.579

—

—

—

—

—

74.664

Test Activities

—

—

—

2.054

—

—

—

—

—

2.054

Technology Maturation and Risk
Reduction (Management Services)

—

—

20.003

20.710

—

—

—

—

—

40.713

Total RDT&E Items

—

—

73.088

44.343

298.521

377.827

192.073

313.959

—

1,299.811

Procurement Items
JSTARS Recap Production

Source: Prepared by CRS based on justification books for Air Force procurement accounts and Air Force research, development, test, and evaluation accounts for
FY2016 and prior years.
Notes: According to the Air Force, the FY 2016 President's Budget decreased the FY 2016 request for JSTARS Recap by $289.794M compared to the FY2015
President’s Budget because the draft acquisition strategy was revised to put more emphasis on the upfront TMRR phase, addressing top integration risks. As a result, the
TMRR phase was extended to 14 months, allowing the government adequate time to validate industry’s system-level design maturity/readiness. Some people may say this
change is a result of the National Defense Authorization Act for FY2015 prohibiting the Air Force from taking any action to retire or to prepare to retire operational
JSTARS aircraft until a report requirement is satisfied.

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

E-3 Sentry (AWACS)35
Figure 3. E-3 Sentry (AWACS)

Source: U.S. Air Force official website, E-3 Sentry (AWACS) Factsheet, November 1, 2003, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104504/e-3-sentry-awacs.aspx.

The E-3 Sentry is an airborne warning and control system (AWACS) aircraft with integrated
command and control battle management (C2BM), surveillance, target detection, and tracking.
The E-3 provides an accurate, real-time picture of the air battlespace to the Joint Air Operations
Center. AWACS provides situational awareness of friendly, neutral, and hostile activity, command
and control of an area of responsibility, battle management of theater forces, all-altitude and allweather surveillance of the battle space, and early warning of enemy actions during joint, allied,
and coalition operations. In effect, AWACS provides an air commander with real-time
information on everything flying within 250 miles of the aircraft.
The E-3 is a modified Boeing 707-320 series commercial airframe with a rotating radar dome.
The dome, 30 feet in diameter, six feet thick, and held 11 feet above the fuselage by two struts,
contains a radar subsystem that permits surveillance to more than 250 miles from the Earth’s
surface up into the stratosphere, over land or water. The radar, combined with an identification
friend or foe (IFF) subsystem can look down to detect, identify, and track enemy and friendly
low-flying aircraft by eliminating ground clutter returns that confuse other radar systems.
Major subsystems in the E-3 are avionics, navigation, communications, sensors (radar and
passive detection) and identification tools. The mission suite includes consoles that display
computer-processed data in graphic and tabular format on video screens. Mission crew members
perform surveillance, identification, weapons control, battle management, and communications
35

Information for this section is from U.S. Air Force E-3 Fact Sheet, November 1, 2003, at http://www.af.mil/
AboutUs/FactSheets/Display/tabid/224/Article/104504/e-3-sentry-awacs.aspx unless noted.

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functions. The radar and computer subsystems on the E-3 can gather and present broad and
detailed battlefield information including position, status, and tracking information on both
friendly and adversary aircraft and ships. That information can be sent to command and control
centers in rear areas or aboard ships. In time of crisis, the data can be forwarded directly to the
President and Secretary of Defense.
In support of air-to-ground operations, the E-3crew can provide direct information needed for
interdiction, reconnaissance, airlift, and close-air support for friendly ground forces. The E-3
crew can also provide information for commanders of air operations to gain and maintain control
of the air battle. As an air defense system, E-3s can detect, identify, and track airborne adversary
forces far from the boundaries of the United States or friendly countries. The E-3 crew can direct
fighter-interceptor aircraft to adversary targets. The E-3 can fly approximately 8 hours without
refueling; its range and on-station time can be increased through in-flight refueling and the use of
an on-board crew rest area.
Engineering, test, and evaluation began on the first E-3 in October 1975. In March 1977, the
552nd Airborne Warning and Control Wing (now 552nd Air Control Wing, Tinker Air Force Base,
Oklahoma), received the first E-3s.
The Air Force inventory includes 31 E-3s in three different versions: 20 E-3Bs (average age 36.1
years), 5 E-3Cs (average age 31.5 years), and 6 E-3Gs (average age 33.2 years).36
The E-3B and E-3C are upgrades of the earliest E-3A. The E-3B is equipped with enhanced
computer capabilities, jam-resistant communications, an austere maritime surveillance capability,
upgraded radios, and five additional mission consoles. E-3B upgrades were completed in 1994.
The E-3Bs received completed Block 30/35 modifications in 2001, which integrated and
enhanced four major subsystems. The E-3C upgrade included five additional mission consoles,
Have Quick anti-jamming equipment, and Block 30/35 upgrades. E-3G is the designation of
aircraft that have completed the Block 40/45 Upgrade described in in the next section, “Block
40/45 Upgrade (E-3G).”37
The Air Force operates E-3s at three locations. The 552nd Air Control Wing at Tinker Air Force
Base, Oklahoma operates E-3s for Air Combat Command. The 18th Wing at Kadena Air Base,
Japan and the 3rd Wing at Elmendorf Air Force Base, Alaska operate E-3s for Pacific Air Forces.
There is one test aircraft at the Boeing in Seattle.

Current E-3 Sustainment and Modernization Efforts38
The FY2015 President’s Budget sought to divest seven E-3 aircraft, which would have reduced
the fleet size from 31 to 24. Congress prohibited the Air Force’s proposed FY2015 E-3 divesture
plan in the National Defense Authorization Act for FY2015,39 and in response, the Air Force re36

“Aircraft Assets & Availability,” Air Force Times, October 20, 2014, p. 19.
“2014 Air Force Almanac,” Air Force Magazine, May 2014, p. 77.
38
Information for current E-3 sustainment and modernization efforts derived from Air Force budget overview
documents, justification books for Air Force procurement accounts, and justification books for Air Force research,
development, test, and evaluation accounts for FY2016 and prior years unless noted. Previous modernization efforts are
not included in this report.
39
P.L. 113-291, Section 136. See the Appendix for full text.
37

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phased the E-3 force reduction of seven aircraft from FY2016 to FY2019. The impact of the
planned divestiture of the seven E-3s on each modification effort, if any, is described in each
section below.
These E-3 sustainment and modernization initiatives currently in the program of record are either
recently completed or are currently in progress. Additional information on each effort is detailed
in the following sections:
•

Block 40/45 Upgrade;

•

Next Generation Identification Friend or Foe (NGIFF);

•

Training, Support, and Infrastructure (TSI);

•

Diminishing Manufacturing Sources Replacement of the Avionics for Global
Operation and Navigation (DRAGON);

•

Electronic Protection (EP);

•

Internet Protocol Enabled Capability (IPEC);

•

Combat Identification (CID) Diminishing Manufacturing Sources (DMS);

•

Air Education and Training Command (AETC) Maintenance Training Device
(MTD) Upgrades – Field Training Detachments;

•

Reliability, Maintainability, and Availability (RM&A) Modifications;

•

Vertical Stabilizer and Rudder Modifications;

•

Low Cost Modifications – Airframe;

•

Low Cost Modifications – Avionics & Mission Systems;

•

Aircraft Spares and Repair Parts;

•

Command and Control, Intelligence, Surveillance, and Reconnaissance (C2ISR);
and

•

Communications Network Upgrade.

Block 40/45 Upgrade (E-3G)
The AWACS Block 40/45 modification upgrades legacy E-3 mission systems computers, display
processors, and displays, and adds a new data architecture designed to enable future
modifications with commercial-off-the-shelf (COTS) hardware. The Block 40/45 Upgrade also
includes an upgrade to Electronic Support Measures sensor data processing; data fusion of both
off-board and on-board sensor data through multi-source integration; a Data Link Infrastructure
upgrade with prioritized data link bandwidth management; new battle management tools;
capability to parse, allow user access to, and integrate updates to Tactical Data Information Link
(TADIL)-J message formats and protocols; enhanced mission and console recording capabilities
while maintaining legacy chat communications and on-board training; modification of system
software to accommodate Diminishing Manufacturing Sources (DMS).
The AWACS Block 40/45 modification is also to be installed on multiple trainers and ground
systems. The development of the training systems, the Mission Crew Training Set and Mission
Computing Maintenance Trainer (MCMT), began in FY2011 and each type was delivered to the

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user in FY2014. Under the MCMT contract line item, the program developed up to 150 ground
systems used for mission planning and post-mission processing at Tinker Air Force Base,
Oklahoma, Elmendorf Air Force Base, Alaska, and Kadena Air Base, Japan, and up to ten
Deployable Ground Systems for use when the aircraft deploys to other locations.
LRIP was approved for six aircraft in November 2008 with one bought in FY2009, two in
FY2010, and three in FY2012. AWACS Block 40/45 Full Rate Production was approved in
November 2012 for the remaining 25 aircraft and technology refresh of the six LRIP aircraft, with
the corresponding production contract awarded on December 27, 2012. With the planned
divestiture of seven E-3 aircraft in FY2019, only 18 of the remaining 25 aircraft will receive the
AWACS Block 40/45 Upgrade, leaving a total of 24 upgraded aircraft in the fleet.
In FY2013, the program office began depot activation to procure test equipment, modules,
training, repair documentation, and other items to support the E-3G. Funding is to support standup of the depot at Warner Robins Air Logistics Complex, Georgia, for repairs of selected units,
and the Avionics Integration Support Facility at Tinker Air Force Base, Oklahoma to perform
mission computing software maintenance activities.
For FY2016, five aircraft are planned to commence modification and three aircraft that began
modifications in FY2015 are expected to be delivered to operational units. Due to end of life
issues for a majority of the programmatic COTS equipment, the program office will have to
contract for engineering support to procure the last four Block 40/45 Upgrade kits as well as
retrofit the six LRIP aircraft. The program office plans to award a contract to procure 10
modification kits, six to be used to retrofit the LRIP aircraft and the other four kits to modify the
remaining Block 30/35 aircraft.

Next Generation Identification Friend or Foe (NGIFF)
The Next Generation Identification Friend or Foe (NGIFF) program funds acquisition and retrofit
of the E-3’s IFF capability. The National Security Agency declared IFF Mode 4 unsecure and
obsolete on November 5, 2003. NGIFF provides the E-3 with enhanced IFF interrogator
operation to add IFF Mode 5 interrogation capability, as required by Joint Requirements
Oversight Council Memo 047-07. While NGIFF did not meet initial operating capacity by the
memo’s target date of FY2014, the current projection of FY2016 is anticipated to meet current
user expectations.
The program develops and integrates a basic Mode 5 capability on Block 30/35 aircraft which
started in FY2008 and full Mode 5 on Block 40/45 aircraft which started in FY2011. Hardware
will be common between the two types of block platforms. Production started in FY2012 after
development of the Block 30/35 capability. Installation on Block 30/35 aircraft is planned to start
in FY15. An Engineering Change Proposal is currently underway to modify the Block 40/45 units
to fully integrate with NGIFF. NGIFF also integrates Mode S, a civilian air traffic control
capability built into the hardware, as funding allows.
As NGIFF modifications conclude prior to the proposed FY2019 divesture of seven E-3s, all 31
aircraft are planned to receive the modification.

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Training, Support, and Infrastructure (TSI)
The Training, Support, and Infrastructure (TSI) program provides continuing management
support for AWACS modernization and enhancement. These activities include managing the
AWACS Development Test and Evaluation (DT&E) infrastructure and tracking and monitoring
AWACS training, support equipment, and program Government Furnished Property. The DT&E
test infrastructure supports development, production, and sustainment projects and maintains
facilities to support AWACS aircraft during system and sub-system testing at Boeing Field,
Washington. Funding is shared between Research, Development, Test, and Evaluation (RDT&E)
and production funds. The TSI assets also support Airborne Early Warning and Control projects
for France, Saudi Arabia, United Kingdom, Japan, and the North Atlantic Treaty Organization
(NATO) on a maintenance fee basis.
Key TSI programs include contract management of the AWACS Avionics Integration Laboratory
integrated with the Block 40/45 configured Advanced Development Lab and the AWACS Radar
Systems Integration Lab/Software Development Facility. These labs support U.S. and
international customers with AWACS system and radar development, production, and
sustainment. TSI also supports trainer/simulator upgrade analysis and requirements definition to
ensure trainers and simulators are kept current with the AWACS baseline.

DMS Replacement of the Avionics for Global Operation and Navigation
(DRAGON)
DMS Replacement of Avionics for Global Operations and Navigation (DRAGON) meets
provides the E-3 fleet with the flight instruments and other avionics for the navigation
performance and surveillance and communication capabilities required to meet international
standards and maintain unrestricted access to global airspace. DRAGON replaces the existing
Global Positioning System Integrated Navigation System with a modern flight management
system that includes Mode 5 IFF and Joint Mission Planning System. The modification also adds
data link communications, voice and data link digital radios, improved visual displays, and
competitive acquisition of DRAGON flight simulators. According to the Air Force, employing
COTS avionics is expected to lower cost, reduce the tech refresh cycle, and enhance life cycle
management. The EMD phase of DRAGON is being executed as a cooperative program between
the United States and NATO.

Electronic Protection (EP)
The Electronic Protection program provides improved radar processing in a specific flight
environment to meet a classified requirement. EP installs an adjunct processor that works in
parallel with the current Radar System Improvement Program (RSIP) system. The EP-processed
radar picture appears on the battle manager’s display in place of the current RSIP output when the
EP radar modes are selected.

Internet Protocol Enabled Capability (IPEC)
The Internet Protocol Enabled Communication program provides the Block 40/45 E-3 with a
medium-bandwidth IP communications capability to connect to the Global Information Grid and
support net-centric operations/warfare. The modification provides a permanent INMARSAT-

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based IP-enabled communications package supporting increased bandwidth SIPRNET and multidomain networks.

Combat Identification (CID) Diminishing Manufacturing Sources
Current AWACS combat identification capability is based upon 1960’s era technology that the Air
Force says is no longer sustainable, requiring an update to retain a significant part of AWACS
overall mission capability. The CID program addresses current shortfalls with a modernized,
persistent Airborne Moving Target Indication BMC2 upgrade. The upgrade is designed to also
provide better integration into Block 40/45 and NGIFF equipped AWACS aircraft.

Air Education and Training Command (AETC) Maintenance Training Devices
(MTD) Upgrades – Field Training Detachments
This program supports fielding and installing modification kits for E-3 Maintenance Training
Devices to keep them consistent with modifications made to the actual E-3.

Reliability, Maintainability, and Availability (RM&A) Modifications
RM&A modifications are designed to help fleet E-3 AWACS to maintain its mandated mission
capable rate of 79%. Modifications include the purchase of aircraft kits, upgrading labs,
installation, technical data and engineering support. RM&A modifications are intended to resolve
issues or reduce maintenance burdens, resolve component obsolescence, or remove deactivated
equipment.

Vertical Stabilizer and Rudder Modifications
This program funds minor modifications to the E-3 vertical stabilizer and rudder.

Low Cost Modifications – Airframe
This is a miscellaneous budget entry to anticipate urgent operational low cost mods that occur in
the execution year and are necessary for continued operational support of Combatant
Commanders.

Low Cost Modifications – Avionics & Mission Systems
This is also a miscellaneous budget entry to anticipate urgent operational low cost mods that
occur in the execution year and are necessary for continued operational support of Combatant
Commanders.

Aircraft Spares and Repair Parts
This program provides funding for repair parts for the E-3.

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Command and Control, Intelligence, Surveillance, and Reconnaissance
(C2ISR)
The Command and Control, Intelligence, Surveillance, and Reconnaissance program investigates
improvements and develops future capabilities of the E-3 AWACS. These efforts include
investigation, analysis, and development to help ensure that the E-3 AWACS successfully
integrates with joint and coalition forces in a net-centric environment. C2ISR primarily supports
pre-systems acquisition in the areas of materiel solution analysis and technology development.
This is accomplished by prototyping and demonstrating new capabilities but also includes
developing an E-3 Modernization & Sustainment Roadmap that projects user capability needs, as
well as materiel solutions for the user needs.

Communications Network Upgrade
The Communications Network Upgrade program provides an upgrade to 20-year-old
communication equipment that has sustainability, diminishing manufacturing sources, and
capability issues. The Multifunctional Information Distribution System (MIDS) Radio System
provides a Link 16 capability with high-jam-resistance, high-speed, crypto-secure computer-tocomputer connectivity in support of every type of military platform from Air Force fighters to
Navy submarines.
Table 6 is the FY2016 budget submission for E-3 Sentry AWACS procurement and E-3 Sentry
AWACS research, development, test, and evaluation programs derived from Air Force budget
justification books. It summarizes prior-year and estimated future-year expenditures for E-3
Sentry AWACS sustainment and modernization programs that are either recently completed or are
currently in progress.

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Table 6. Current E-3 AWACS Sustainment and Modernization Efforts
(in millions of dollars)
Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total
Cost

Block 40/45 Upgradea

543.807

114.439

191.284

183.308

226.429

103.643

58.221

29.533

—

1,450.664

Next Generation Identification Friend or
Foe (NGIFF)

28.403

17.277

9.899

6.786

3.253

—

—

—

—

65.618

Training, Support, and Infrastructure (TSI)

10.270

2.845

3.335

4.015

3.902

3.716

4.044

4.165

—

36.292

Diminishing Manufacturing Sources
Replacement of the Avionics for Global
Operation and Navigation (DRAGON)

—

—

—

—

54.689

89.668

86.344

117.856

—

348.557

Electronic Protection (EP)

—

—

—

—

1.288

11.960

12.930

11.870

—

38.048

Internet Protocol Enabled Capability
(IPEC)

—

—

—

—

12.961

9.263

17.904

5.488

—

45.616

Combat Identification (CID) Diminishing
Manufacturing Sources (DMS)

—

—

—

—

—

—

4.491

14.268

—

18.759

Air Education and Training Command
(AETC) Maintenance Training Device
(MTD) Upgrades – Field Training
Detachments

4.916

0.100

0.608

0.687

0.693

0.706

0.719

0.731

—

9.160

Reliability, Maintainability, and Availability
Modifications

15.216

3.590

2.266

0.825

0.668

0.320

0.095

0.505

—

23.485

Vertical Stabilizer and Rudder
Modifications

0.077

0.238

0.107

0.665

0.287

0.135

0.018

—

—

1.527

Low Cost Modifications – Airframe

0.100

0.012

0.138

0.100

0.100

0.031

—

—

—

0.481

Low Cost Modifications – Avionics &
Mission Systems

0.100

0.012

0.138

0.100

0.100

0.031

—

—

—

0.481

Aircraft Spares and Repair Parts

—

11.681

2.957

16.234

23.806

22.682

24.132

24.552

126.044

602.889

150.194

210.732

212.720

328.176

242.155

208.898

208.968

—
—

Procurement Items

Total Procurement Items

2,164.732

Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total
Cost

Block 40/45 Upgrade

—

11.268

—

—

—

—

—

—

—

—

Next Generation Identification Friend or
Foe (NGIFF)

—

21.554

1.500

—

—

—

—

—

—

—

Training, Support, and Infrastructure (TSI)

—

8.371

11.472

11.139

—

—

—

—

—

—

Diminishing Manufacturing Sources
Replacement of the Avionics for Global
Operation and Navigation (DRAGON)

—

89.482

129.150

88.277

—

—

—

—

—

—

Electronic Protection (EP)

—

9.882

18.604

26.092

—

—

—

—

—

—

Internet Protocol Enabled Capability
(IPEC)

—

—

16.575

13.974

—

—

—

—

—

—

Combat Identification (CID) Diminishing
Manufacturing Sources (DMS)

—

—

—

9.435

—

—

—

—

—

—

Command and Control, Intelligence,
Surveillance, and Reconnaissance (C2ISR)

—

2.847

3.503

3.608

—

—

—

—

—

—

Communications Network Upgrade

—

—

—

9.287

—

—

—

—

—

—

3,706.552

143.404

180.804

161.812

108.766

82.371

100.371

110.466

—

—

RDT&E Items

Total RDT&E Items

Source: Prepared by CRS based on justification books for Air Force procurement accounts and Air Force research, development, test, and evaluation accounts for
FY2016 and prior years.
a.

Procurement funding for the Block 40/45 Upgrade was previously contained in Weapon System Code (WSC) E00300, but as part of the Major Programs
Transparency Act and starting in FY2015, the AWACS Block 40/45 Upgrade was moved to WSC E34045. Prior year funding remains in WSC E00300. The numbers
in this table summarize spending in both WSCs.

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Previous E-3 Recapitalization Efforts
E-10 Program
See “Previous E-8C Recapitalization Efforts” section for a brief discussion of a previous E-3
recapitalization effort under the E-10 program.

Current E-3 Recapitalization Efforts
Air Force budget documents do not specify a plan to recapitalize the E-3 in the near term. The Air
Force is focusing on modernizing the E-3 to the E-3G variant (Block 40/45 Upgrade) which is
expected to be completed by 2020.

RC-135 Family of Aircraft
The RC-135 program consists of three unique models of 22 operational aircraft including 17 RC135V/W RIVET JOINT, 2 RC-135U COMBAT SENT, and 3 RC-135S COBRA BALL.40 In
addition, there are three TC-135W aircraft used for training and one NC-135W used for testing41
for the RC-135V/W RIVET JOINT. All operational and training RC-135 aircraft are assigned to
the 55th Wing, Offutt Air Force Base, Nebraska.42
A 2008 RC-135 viability assessment reported that despite the fleet average airframe age of 44
years and total of 38,000 flight hours as of the end of FY2007, the RC-135 should be able to
continue to meet the Combatant Commanders’ needs through at least 2040. The viability
assessment also summarized that the RC-135 fleet has experienced significant improvements in
reliability, maintainability, and availability since FY2001.

40

Unlike the E-3 Sentry or E-6 Mercury, these RC-135 variants carry the names of the programs under which they
were originally developed. Although the names are not acronyms, they are typically rendered in all-capitals, and CRS
has retained that style.
41
Department of Defense, Model Designation of Military Aerospace Vehicles, DOD Directive 4120.15-L, May 12,
2004, p. 29.
42
U.S. Air Force RC-135V/W RIVET JOINT Factsheet, May 23, 2012, at http://www.af.mil/AboutUs/FactSheets/
Display/tabid/224/Article/104608/rc-135vw-rivet-joint.aspx, U.S. Air Force RC-135U COMBAT SENT Factsheet,
February 14, 2005, at http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104495/rc-135u-combatsent.aspx, U.S. Air Force RC-135S COBRA BALL Factsheet, February 16, 2012, at http://www.af.mil/AboutUs/
FactSheets/Display/tabid/224/Article/104498/rc-135s-cobra-ball.aspx, “2014 Air Force Almanac,” Air Force
Magazine, May 2014, pp. 79-80.

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RC-135V/W RIVET JOINT43
Figure 4. RC-135V/W RIVET JOINT

Source: U.S. Air Force official website, RC-135V/W RIVET JOINT Factsheet, May 23, 2012, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104608/rc-135vw-rivet-joint.aspx.

The RC-135V/W RIVET JOINT reconnaissance aircraft supports theater and national level
leaders with near real time on-scene intelligence collection, analysis, and dissemination
capabilities. The aircraft is an extensively modified C-135. Those modifications are primarily
related to its on-board sensor suite, which allows the mission crew to detect, identify, and
geolocate signals throughout the electromagnetic spectrum. The mission crew can forward
information in a variety of formats via an extensive communications suite. The interior seats
more than 30 people, including the cockpit crew, electronic warfare officers, intelligence
operators, and in-flight maintenance technicians.
The current RC-135 fleet is the latest iteration of modifications to this pool of C-135 aircraft
going back to 1962. RIVET JOINT achieved initial operating capability in January 1964.
According to Air Force data, the average age of the RC-135V RIVET JOINT is 49.8 years, the
43

Information for this section is from U.S. Air Force RC-135V/W RIVET JOINT Factsheet, May 23, 2012, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104608/rc-135vw-rivet-joint.aspx unless noted.

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RC-135W RIVET JOINT is 51.8 years, the TC-135W trainer aircraft is 52.1 years, and the NC135W test aircraft is 52.3 years.44

RC-135U COMBAT SENT45
Figure 5. RC-135U COMBAT SENT

Source: U.S. Air Force official website, RC-135U COMBAT SENT Factsheet, February 14, 2005, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104495/rc-135u-combat-sent.aspx.

The RC-135U COMBAT SENT provides strategic electronic reconnaissance information to
national leaders and theater commanders. The COMBAT SENT locates, identifies, collects, and
examines foreign military land, naval, and airborne radar signals, providing strategic analysis.
Collected data is stored for further analysis by electronic systems theorists and the intelligence
community. Information garnered from the data helps determine detailed operating characteristics
and capabilities of foreign systems. Evasion techniques and equipment are then developed from
this knowledge to detect, warn of, or defeat these electronic systems.
The RC-135U COMBAT SENT is composed of a wide variety of commercial-off-the-shelf and
proprietary hardware and software. The current configuration allows for both manual and
automatic analysis of electronic signals. Communication equipment includes high frequency, very
high frequency, and ultra-high frequency radios. The navigation equipment incorporates ground
navigation radar, a solid state Doppler system, and an inertial navigation system that merges
44

“Aircraft Assets & Availability,” Air Force Times, October 20, 2014, p. 19.
Information for this section is from U.S. Air Force RC-135U COMBAT SENT Factsheet, February 14, 2005, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104495/rc-135u-combat-sent.aspx unless noted.
45

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celestial observations and Global Positioning System data. Although the flight crew stations are
similarly configured, the reconnaissance equipment is slightly unique within each airframe. The
aircraft are identified by their distinctive antennae arrays on the “chin” and wing tips, large cheek
fairings, and extended tail. All RC-135U COMBAT SENT aircraft are equipped with an aerial
refueling system, theoretically yielding unlimited flying range.
COMBAT SENT crews include two pilots, one navigator, two airborne systems engineers, at least
ten electronic warfare officers, and at least six electronic, technical, and area specialists.
Initial operating capability was in April 1964. According to Air Force data, the average age of the
RC-135U COMBAT SENT is 49.5 years.

RC-135S COBRA BALL46
Figure 6. RC-135S COBRA BALL

Source: U.S. Air Force official website, RC-135S COBRA BALL Factsheet, February 16, 2012, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104498/rc-135s-cobra-ball.aspx.

Equipped with a sophisticated array of optical and electronic sensors, recording media, and
communications equipment, the RC-135S COBRA BALL collects optical and electronic data on
ballistic missile targets. Its operators track and monitor missiles during boost and re-entry phases
to provide reconnaissance for treaty verification and theater ballistic missile proliferation.47 This
data is also used to develop U.S. missile defense concepts.
COBRA BALL crews include two pilots, one navigator, three electronic warfare officers, two
airborne systems engineers, and two or more airborne mission specialists.

46

Information for this section is from U.S. Air Force RC-135S COBRA BALL Factsheet, February 16, 2012, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104498/rc-135s-cobra-ball.aspx unless noted.
47
“2014 Air Force Almanac,” Air Force Magazine, May 2014, pp. 79-80.

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The current RC-135S aircraft trace their lineage to C-135 aircraft originally modified in 1961.
Initial operating capability for the RC-135S COBRA BALL was in March 1972. According to Air
Force data, the average age of the RC-135S COBRA BALL is 52.3 years.

Current RC-135 Sustainment and Modernization Efforts48
As the most numerous variant, the RC-135V/W RIVET JOINT drives the integration and
modification upgrade strategy for the entire RC-135 fleet. The majority of the modification
budget is directly related to RIVET JOINT baseline strategy enhancements which subsequently
transfer into follow-on enhancements for COBRA BALL and COMBAT SENT.
The RC-135 program aims to maintain collection parity with evolving and emerging adversarial
weapons systems used by state and non-state actors. The baseline upgrade strategy requires
purchase agreements for long-lead items that take approximately 12 months from contract award
to delivery. Items contracted for purchase and integration in a given baseline upgrade are bought
in the first year of the procurement funding cycle and are installed in the subsequent year.
According to the Air Force, this acquisition strategy has been successful in maintaining combat
capability in the ISR arena over the last 40 years.
The following RC-135 sustainment and modernization initiatives, currently in the program of
record, are either recently completed or are currently in progress. Additional information on each
effort is detailed in the following sections:
•

RIVET JOINT Baseline Modification;

•

COMBAT SENT Baseline Modification;

•

COBRA BALL Baseline Modification;

•

Aircraft Spares and Repair Parts;

•

Defense Airborne Recce Projects (DARP) RC-135;

•

Baseline Configuration Development; and

•

Airborne SIGINT Development - RC-135 RIVET JOINT.

RIVET JOINT Baseline Modification
Current modernization efforts concentrate on completing the integration and fielding efforts of
the RIVET JOINT’s Baseline 11 and initial integration of Baseline 12. Baseline 11 subsystem
upgrades consist of precision multi-angle direction finding communications intelligence (DF
COMINT) capability, electronic intelligence (ELINT) recorder expansion, precision ELINT
digital SIGINT system integration, Wideband Global Satellite (WGS) enhanced integration,
increased near real time national tactical integration, continued cockpit avionics enhancements to
include addressing any obsolescence issues, new steerable beam antenna, weight reduction phase

48
Information for current RC-135 sustainment and modernization efforts derived from justification books for Air Force
procurement accounts and research, development, test, and evaluation accounts for FY2016 and prior years unless
noted. Previous modernization efforts are not included in this report.

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3, improved operator interface and reporting tools, and enhancing capabilities in dense signal
environments.
Baseline 12 subsystem upgrades consist of increased digital signal exploitation, increased digital
signal recorder bandwidth, enhanced spatial processing/exploitation, enhanced weather radar,
digitally enhanced electronic flight instrument system, AF-DCGS interoperability, operator work
station 3-D map projection, enhanced operator reporting management tools, modernized
communications security protocols, and new steerable beam antenna.

COMBAT SENT Baseline Modification
Current COMBAT SENT modernization efforts focus on Baseline 5 enhancements. Baseline 5
subsystem upgrades consist of WGS reachback connectivity, precision ELINT systems
replacement, liquid cooling system, super wideband receiver, airborne tracking system, improved
operator interface and reporting tools, integration of the RIVET JOINT Baseline 11 COMINT
suite, and enhancing capabilities in dense signal environments. COMBAT SENT Baseline 5
configurations most closely align with the RIVET JOINT Baseline 11 configuration.

COBRA BALL Baseline Modification
Current COBRA BALL modernization efforts also focus on the same Baseline 5 enhancements as
COMBAT SENT.

Aircraft Spares and Repair Parts
This program provides funding for repair parts for the RC-135 family of aircraft.

Defense Airborne Recce Projects (DARP) RC-135
Detailed information on the Defense Airborne Recce Projects RC-135 program remains
classified. This program is reported in accordance with Title 10, U.S. Code, Section 119(a)(1) in
the Special Access Program Annual Report to Congress.

Baseline Configuration Development
RC-135 operational systems development and enhancement activities support the design studies,
engineering analysis, non-recurring engineering, and other efforts associated with integrating and
modifying the RC-135s and their specialized mission systems, both air and ground. The program
seeks to use COTS based solutions and mitigate the impact of Diminishing Manufacturing
Sources (DMS)/Vanishing Vendor Items.
In FY2016, this program plans to support the RIVET JOINT Baseline 12 and 13, COMBAT
SENT Baseline 5, and COBRA BALL Baseline 5 configurations.
RIVET JOINT Baseline 13 upgrades consist of, but are not limited to, providing a continuous
recording capability, Super Wideband Compressive Receiver and Nyquist Folding Receiver,
global air traffic management avionics upgrades (e.g., new autopilot), Mode 5 IFF system, and

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family of beyond-line-of-sight terminals advanced extremely high frequency communications
suite.

Airborne SIGINT Development - RC-135 RIVET JOINT
The Airborne SIGINT Development - RC-135 RIVET JOINT program supports design studies,
engineering analysis, non-recurring engineering, and other efforts associated with the integration
and modification of the RC-135 SIGINT sensors and their associated air and ground components.
The program seeks COTS-based solutions to field needed capabilities. Funding is split among the
RC RIVET JOINT, COMBAT SENT, and COBRA BALL programs. Funding reflects the SIGINT
Capabilities Working Group priorities and the accomplishment of other Airborne SIGINT
Enterprise initiatives.
Table 7 is the FY2016 budget submission for RC-135 procurement and RC-135 research,
development, test, and evaluation programs derived from Air Force budget justification books. It
summarizes prior-year and estimated future-year expenditures for RC-135 sustainment and
modernization programs that are either recently completed or are currently in progress.

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Table 7. Current RC-135 Sustainment and Modernization Efforts
(in millions of dollars)
Total
Cost
FY2014a

Total
Cost
FY2015b

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

154.940

146.745

143.388

186.270

189.421

172.665

175.773

10.444

10.539

6.633

6.728

6.893

6.834

6.957

9.129

6.062

6.144

6.325

6.537

6.776

6.898

Aircraft Spares and Repair Parts

—
—
—
—

28.280

57.119

54.016

48.632

49.407

50.331

Defense Airborne Recce Projects
(DARP) RC-135

—

20.577

24.710

25.072

25.496

25.933

Total Procurement Items

—

223.370

245.175

235.253

273.451

RDT&E Items

Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

13.491

13.516

32.556

46.047

Procurement Items
RIVET JOINT Baseline Modification
COMBAT SENT Baseline Modification
COBRA BALL Baseline Modification

Baseline Configuration Development
Airborne SIGINT Development - RC135 RIVET JOINT
COBRA BALLc
Total RDT&E Items

Prior
Years

—
—
—
—

Cost to
Complete

Total Cost
1,169.202

51.237

—
—
—
—

26.393

26.861

—

175.042

278.191

262.999

267.726

—

1,786.165

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total Cost

13.245

14.184

14.366

14.462

14.720

Continuing

Continuing

15.007

41.846

23.152

43.611

51.430

58.353

Continuing

Continuing

28.523

55.091

37.336

57.977

65.892

73.073

Continuing

Continuing

55.028
47.871
339.022

Source: Prepared by CRS based on justification books for Air Force procurement accounts and Air Force research, development, test, and evaluation accounts for
FY2016 and prior years.
a.

FY2014 funding totals includes an Overseas Contingency Operations (OCO) add of $2.7M for X-Net integration.

b.

FY2015 funding totals includes a Congressional Add of $10.6M for baseline modernization shortfalls.

c.

RDT&E budget exhibits for this program were not available due to classification.

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Previous RC-135 Recapitalization Efforts
E-10 Program
See “Previous E-8C Recapitalization Efforts” section for a brief discussion of a previous RC-135
recapitalization effort under the E-10 program.

Current RC-135 Recapitalization Efforts49
The RIVET JOINT Baseline 11 and 12 integration efforts address the 2012 RC-135 MultiAttribute Utility Assessment (MUA) that detailed operational effectiveness, cost, and program
analyses of the alternative weapon system configurations. The MUA determined that retaining
and sustaining the RC-135V/W airframe offers the highest assessed weapons system utility
(measured as a benefit of cost-to-risk ratio) over the 25-year assessment period.

49

Information for current RC-135 recapitalization efforts derived from justification books for Air Force procurement
accounts and research, development, test, and evaluation accounts for FY2016 and prior years unless noted.

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WC-135 Constant Phoenix50
Figure 7. WC-135 Constant Phoenix

Source: U.S. Air Force official website, WC-135 Constant Phoenix Factsheet, May 27, 2005, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104494/wc-135-constant-phoenix.aspx.

The WC-135 Constant Phoenix atmospheric collection aircraft supports national leaders by
collecting particulate and gaseous effluents and debris to detect nuclear weapons testing and
detonations from accessible regions of the atmosphere.
General Dwight D. Eisenhower commissioned the Constant Phoenix program on September 16,
1947, when he charged the Army Air Forces with the overall responsibility for detecting atomic
explosions anywhere in the world. In September 1949, a WB-29 flying between Alaska and Japan
detected nuclear debris from Russia’s first atomic test, an event thought not possible until mid1950. Beginning in August 1950, WB-50 aircraft were converted for the air-sampling mission
over a two-year period. WC-135 aircraft began replacing the WB-50s in December 1965 and
became the workhorse of the atmospheric collection program.
Currently, the air-sampling mission supports the Limited Nuclear Test Ban Treaty of 1963, which
prohibits any nation from above ground nuclear weapons testing. WC-135s are currently the only
aircraft in the inventory conducting air-sampling operations.
50

Information for this section is from U.S. Air Force WC-135 Constant Phoenix Factsheet, May 27, 2005, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104494/wc-135-constant-phoenix.aspx unless noted.

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The aircraft is a modified C-135B or EC-135C platform. The Constant Phoenix’s modifications
are primarily related to its on-board atmospheric collection suite, which allows the mission crew
to detect radioactive “clouds” in real time. The aircraft is equipped with external flow-through
devices to collect particulates on filter paper and a compressor system for whole air samples
collected in holding spheres. There are two versions of the WC-135, a WC-135C and a WC135W, with one of each version in the active inventory. According to Air Force data, the age of
the WC-135C is 50.2 years and the age of the WC-135W is 52.3 years.
The aircraft and cockpit crew are assigned to the 55th Wing while the special equipment operators
are assigned to Detachment 1, Air Force Technical Applications Center, both located at Offutt Air
Force Base, Nebraska.

Current WC-135 Sustainment and Modernization Efforts51
Air Force budget documents do not specify a plan to modernize the WC-135 Constant Phoenix
aircraft in the near term.

Current WC-135 Recapitalization Efforts52
Air Force budget documents do not specify a plan to recapitalize the WC-135 Constant Phoenix
aircraft in the near term.

51
Information for current WC-135 sustainment and modernization efforts derived from justification books for Air
Force procurement accounts and research, development, test, and evaluation accounts for FY2016 and prior years
unless noted. Previous modernization efforts are not included in this report.
52
Information for current WC-135 recapitalization efforts derived from justification books for Air Force procurement
accounts and research, development, test, and evaluation accounts for FY2016 and prior years unless noted.

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OC-135B Open Skies53
Figure 8. OC-135B Open Skies

Source: U.S. Air Force official website, OC-135B Open Skies Factsheet, February 1, 2001, at http://www.af.mil/
AboutUs/FactSheets/Display/tabid/224/Article/104496/oc-135b-open-skies.aspx.

The OC-135B Open Skies Observation Aircraft supports the Open Skies Treaty.54 The aircraft
flies unarmed observation flights over participating parties of the treaty.

53
Information for this section is from U.S. Air Force OC-135B Open Skies Factsheet, February 1, 2001, at
http://www.af.mil/AboutUs/FactSheets/Display/tabid/224/Article/104496/oc-135b-open-skies.aspx unless noted.
54
The Treaty on Open Skies was first proposed by President Eisenhower to the former Union of Soviet Socialist
Republics at the Geneva Conference of 1955. In the context of the Cold War, this bilateral proposal was rejected by the
Soviet Union and lay dormant for a generation. In May 1989, Open Skies was proposed as an instrument of confidence
building, which would promote and consolidate the international trends toward openness already in progress. Formal
negotiations on a Treaty on Open Skies began in Ottawa in February 1990, and continued in Budapest in April and
May 1990. At that time, however, the Soviet Union was still not prepared to open all of its territory to aerial
observation. Following the stalemate at Ottawa and Budapest, the Open Skies negotiations lapsed for over a year,
although the United States and others continued to press the issue bilaterally. After the abortive coup in Moscow in
August 1991 the former Soviet Union changed its position and agreed to open all of its territory for aerial observation.
This change cleared the way for productive negotiations, which commenced in November 1991 in Vienna, leading to
the signing of the Treaty in Helsinki on March 24, 1992. The Treaty on Open Skies is designed to enhance mutual
understanding and confidence by giving all participating countries, regardless of size, a direct role in gathering
information about military forces and activities of concern to them. The Treaty on Open Skies is based on complete
territorial openness, on the use of unarmed observation aircraft, on sensors on board those aircraft, and on quotas of
observation flights which each participating country is willing to accept, and entitled to conduct, annually. (Source:
Department of State, Letter of Submittal - Treaty on Open Skies, August 12, 1992, http://www.state.gov/t/avc/trty/
102337.htm#submittal.)

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The aircraft are modified WC-135Bs dating from the early 1960s. One aircraft was converted to
an OC-135B in October 1993. Two additional operational OC-135B aircraft were delivered in
1996 and remain the in the active inventory. The original OC-135B is in permanent storage at the
Aircraft Maintenance and Regeneration Center at Davis Monthan Air Force Base, Arizona.
According to the Air Force, the average age of the OC-135B Open Skies is 52.3 years.
Since the primary mission of the OC-135B is to take pictures, most of the installed equipment and
systems provide direct support to the cameras and the camera operator. Cameras installed include
one vertical and two oblique KS-87E framing cameras used for low-altitude photography
(approximately 3,000 feet above the ground) and one KA-91C panoramic camera, which scans
from side to side to provide a wide sweep for each picture (used for high altitude photography at
approximately 35,000 feet). The interior seats 35 people, including the cockpit crew, aircraft
maintenance crew, foreign country representatives, and crew members from the Department of
Defense’s Defense Threat Reduction Agency (DTRA).
The integrated data annotation and recording system processes navigational, altitude, time, and
camera signals to annotate each picture with correct position, altitude, time, roll angle, and other
information. In addition, this system records every picture taken according to camera, frame, and
navigational position. Two Barco 12-inch VGA color monitors display camera annotation and
other camera data on screen for the sensor operator and observer use.
The OC-135B Open Skies aircraft are assigned to Air Combat Command’s 55th Wing, Offutt Air
Force Base, Nebraska for operations, training, and maintenance. When tasked, Air Combat
Command’s role is to transport a DTRA observation team to an Open Skies point of entry airport,
conduct the observation flight, then return the team to the continental United States.

Current OC-135B Sustainment and Modernization Efforts55
There is one sustainment and modernization initiative currently in progress in the OC-135B
program of record.

OC-135 Open Skies Sensors
The Open Skies Sensors program addresses the requirements in Presidential Policy Directive-15
(PPD-15), which on March 1, 2012 directed an upgrade to the sensors on the current aircraft by
replacing film-based cameras with available electro-optical sensors. Current film cameras are
nearly obsolete, unreliable, hard and increasingly expensive to maintain, and repair parts must be
individually manufactured. In addition, film manufacturers are discontinuing production of the
film stock. The ultimate imagery product customer also desires digital format products.
This camera replacement program will replace the wet film cameras with modern, digital cameras
expected to be more reliable, maintainable, and cost effective. The customer should be able to
more readily use the imagery products and equipment service life is expected to be extended
significantly.
55
Information for current OC-135B sustainment and modernization efforts derived from justification books for Air
Force procurement accounts and research, development, test, and evaluation accounts for FY2016 and prior years
unless noted. Previous modernization efforts are not included in this report.

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Table 8 is the FY2016 budget submission for OC-135B research, development, test, and
evaluation programs derived from Air Force budget justification books. It summarizes prior-year
and estimated future-year expenditures for OC-135 sustainment and modernization programs that
are either recently completed or are currently in progress.

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Table 8. Current OC-135B Sustainment and Modernization Efforts
(in millions of dollars)

RDT&E Items
OC-135 Open Skies Sensors
Total RDT&E Items

Prior
Years

Total
Cost
FY2014

Total
Cost
FY2015

Total
Cost
FY2016

Total
Cost
FY2017

Total
Cost
FY2018

Total
Cost
FY2019

Total
Cost
FY2020

Cost to
Complete

Total Cost

—

1.430

13.222

12.137

4.892

—

—

—

Continuing

Continuing

—

1.430

13.222

12.137

4.892

—

—

—

Continuing

Continuing

Source: Prepared by CRS based on justification books for Air Force procurement accounts and Air Force research, development, test, and evaluation accounts for
FY2016 and prior years.

U.S. Command and Control and Intelligence, Surveillance, and Reconnaissance Aircraft

Current OC-135B Recapitalization Efforts56
Air Force budget documents do not specify a plan to recapitalize the OC-135B Open Skies
aircraft in the near term.

E-6B Mercury57
Figure 9. E-6B Mercury

Source: U.S. Navy official website, at http://www.navair.navy.mil/img/uploads/E-6B%20fly%201.JPG.

The E-6B Mercury is communications relay and strategic airborne command post aircraft. The E6B provides airborne command, control, and communications between the National Command
Authority (NCA) and U.S. strategic and non-strategic forces. The E-6 replaced the aging EC130Q in the performance of the Navy’s TACAMO (“Take Charge and Move Out”) mission.
TACAMO links the NCA with naval ballistic missile forces during times of crisis. The aircraft
carries a very low frequency communication system with dual trailing wire antennas.
Boeing derived the E-6A from its commercial 707-320 aircraft. The E-6A was assembled on the
same production line as the E-3 Sentry AWACS. The Navy awarded Boeing a full-scale
56

Information for current OC-135B recapitalization efforts derived from justification books for Air Force procurement
accounts and research, development, test, and evaluation accounts for FY2016 and prior years unless noted.
57
Information for this section is from U.S. Navy E-6B Mercury Fact File, February 17, 2009, at http://www.navy.mil/
navydata/fact_display.asp?cid=1100&tid=800&ct=1 unless noted.

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development contract for the E-6A in 1983 and the prototype E-6A rolled out from Boeing’s
Renton, Washington factory in December 1986. The first flight was in February 1987. The Navy
accepted the first E-6A in August 1989 and the final airplane in May 1992.58 The Navy E-6Bs
were the last 16 aircraft to roll off of Boeing’s 707 assembly line after 30 years of production.59
The E-6B version was conceived as a replacement for the Air Force’s Airborne Command Post
due to the age of the EC-135 fleet. The E-6B modified an E-6A by adding battlestaff positions
and other specialized equipment. The E-6B is a dual-mission aircraft capable of fulfilling either
the E-6A mission or the airborne strategic command post mission and is equipped with an
airborne launch control system, capable of launching U.S. land based intercontinental ballistic
missiles. The first E-6B aircraft was accepted in December 1997 and the E-6B assumed its dual
operational mission in October 1998. The E-6 fleet was completely modified to the E-6B
configuration in 2003.
There are 16 aircraft in the E-6B fleet. The E-6B has a normal crew of 13 members (three pilots,
two naval flight officers, and eight enlisted aircrew) and a battlestaff crew of 22. All E-6B aircraft
are assigned to Strategic Communications Wing One (SCW-1) at Tinker Air Force Base,
Oklahoma.60

Current E-6B Sustainment and Modernization Efforts61
The following E-6B sustainment and modernization initiatives, currently in the program of
record, are either recently completed or are currently in progress. Additional information on each
effort is detailed in the following sections:
•

Safety Deficiencies;

•

Tech Insertion;

•

Service Life Extension Program (SLEP);

•

Communications Upgrade;

•

Block I;

•

Multi-Role Tactical Common Data Link (MR-TCDL);

•

Auxiliary Power Unit (APU);

•

Family of Advanced Beyond-Line-of-Sight Terminals/Presidential and National
Voice Conferencing (FAB-T/PNVC);

•

Common Ground Equipment; and

•

Navy Strategic Communications Project.

58

Boeing, Airborne Early Warning Systems History, at http://www.boeing.com/boeing/history/boeing/airborne.page.
U.S. Navy Website, VQ-4, accessed March 27, 2014, at http://www.tacamo.navy.mil/vq4/vq4_home.html.
60
U.S. Navy Website, E-6B Mercury Factsheet, accessed March 27, 2014, at http://www.tacamo.navy.mil/
factsheets.html.
61
Information for current E-6B sustainment and modernization efforts derived from justification books for Navy
procurement accounts and research, development, test, and evaluation accounts for FY2016 and prior years unless
noted. Previous modernization efforts are not included in this report.
59

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Safety Deficiencies
The Safety Deficiencies program is intended to correct high risk aircraft safety hazards to protect
personnel and equipment. Federal agency directives, aging aircraft material condition, and the
operational environment generate safety hazards for correction. Modifications under this program
include Fuel Quantity Indicating System installation, aircraft acoustic thermal blankets
replacement, Kapton wiring replacement, and other safety deficiencies that require correction.

Tech Insertion
The Tech Insertion program seeks to correct aircraft obsolescence, supportability, weight
management, and interoperability deficiencies through new technology insertion. Modifications
under this program include CRYPTO modernization, brakes, seats, glare shield, High Power
Transmit Set (HPTS) and the HPTS Camera, Automated Dependent Surveillance Broadcast, High
Frequency Automatic Link Establishment, Common Very Low Frequency Receiver,
Communication Navigation and Surveillance Air Traffic Management, Missions Operation
Monitor, aircraft electrical system, Airborne Launch Control System (ALCS), and other tech
insertion corrections.

Service Life Extension Program (SLEP)
The Service Life Extension Program (SLEP) extends the service life of the aircraft to at least
2040 through airframe strengthening and structural data recording and analysis. This program
also includes just in time modifications to prevent aircraft grounding due to fatigue life expended.
Modifications under this program include Individual Aircraft Tracking System and Crash
Survivable Flight Incident Recorder Phase 2.

Communications Upgrade
The Communications Upgrade program installs expanded aircraft communication bandwidth
capability required to improve Airborne Command Post (ABNCP) operations. Modifications
under this program include Internet Protocol (IP) Phase 1 connectivity and wideband
communication capability to enable voice, video, and data services, International
Marine/Maritime Satellite (INMARSAT), IP Phase 3, and removal of Utility Trailing Wire
Antenna.

Block I
The Block I program aims to correct ABNCP operational test deficiencies to improve mission
capability, readiness, and legacy system obsolescence. Modifications under this program include
Block I, Very Low Frequency Transmit Terminal, and technology upgrade.

Multi-Role Tactical Common Data Link (MR-TCDL)
The Multi-Role Tactical Common Data Link (MR-TCDL) program installs expanded aircraft
communication bandwidth capability required to interoperate with U.S. Strategic Command’s
National Command and Control Architecture.

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Auxiliary Power Unit (APU)
The Auxiliary Power Unit program installs an improved APU to meet increased aircraft power
requirements.

Family of Advanced Beyond-Line-of-Sight Terminals/Presidential and
National V

[Text truncated at 120,000 characters. The full text is on the page linked above.]

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/crs%3AR44108. Public record. Not legal advice.
