V-22 Osprey Aircraft: Background and Issues for Congress

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V-22 Osprey Aircraft: Background and Issues

for Congress

September 12, 2025

Congressional Research Service

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R48703

SUMMARY

V-22 Osprey Aircraft: Background and Issues

for Congress

R48703

September 12, 2025

Jennifer DiMascio

Analyst in U.S. Defense

The V-22 Osprey is a joint-service, multi-mission, medium-lift rotorcraft. The V-22 is a type of

Policy

aircraft known as a tilt-rotor, which is a unique design for a crewed military aircraft. A tilt-rotor

takes off and lands vertically like a helicopter but flies forward like an airplane by tilting the rotor

blades atop each wing forward like a turboprop aircraft. The Osprey can take off or land without

a runway or from the deck of a ship in ways that fixed-wing aircraft cannot, and the combination

of vertical and forward flight adds speed and range compared with traditional helicopters. The V22 was developed in the 1980s and declared capable of conducting initial operations in 2007. U.S. military personnel have

since flown the aircraft in combat operations in Iraq, Afghanistan, and elsewhere.

The Department of the Navy manages a V-22 Joint Program Office (JPO) for development, support, fielding, and disposal of

the aircraft. The V-22 program office works with Bell Helicopter Textron of Fort Worth, TX, and Boeing Helicopters of

Philadelphia, PA, to manufacture the aircraft in three types, or variants, one each for the Marine Corps, Air Force Special

Operations Command (AFSOC), and the Navy. A prototype of the V-22 was made in 1988 and flew for the first time a year

later. The U.S. Department of Defense (DOD) has purchased 360 V-22s for the Marines, 53 for the Navy, and 56 for

AFSOC, some of which are still in production. DOD is scheduled to close the production line in FY2028. The United States

has exported the V-22 to Japan, which has 17 Ospreys.

As of July 2025, 65 military personnel and civilians have died in mishaps involving V-22 aircraft. That figure includes 30

fatalities before 2007, when the aircraft was declared ready for initial operations, and 35 after 2007. Since 2022, V-22s have

experienced four fatal mishaps that killed 20 servicemembers and injured another 20. Accident investigation reports state that

component failures were the primary cause of at least two of those mishaps. DOD officials have said that similar components

may have been at fault for additional mishaps and have restricted flights to within 30 minutes of a landing zone. Citing fatal

V-22 crashes in 2022 and 2023, some Members of the 118th and 119th Congresses have expressed concern about the

platform’s safety. The House Committee on Government Oversight in December 2023 conducted an investigation into the V22 program and in June 2024 held a hearing on the topic.

The V-22 JPO has stated that it is working to return the Osprey to full operations in 2026 and is pursuing several upgrades to

the aircraft’s parts and components to improve safety and reliability. The Marine Corps, Air Force, and Navy are also

modifying training, and implementing new operating procedures.

Some Members of Congress have also expressed concerns about whether the design of the V-22 can provide any lessons for

the Army’s development of a new tilt-rotor aircraft, known as the Future Long-Range Assault Aircraft. Congress may

consider whether or not to provide oversight of such topics and/or whether to provide funding for such upgrades. In

conducting oversight of the V-22, Congress may consider the following issues, among others:

•

the size of the V-22 fleets for the Marine Corps, Air Force, and Navy;

the logistics of carrier-based V-22s;

funding for V-22 upgrades and their potential effects on safety;

access to V-22 safety investigation reports; and

training for V-22 maintenance personnel.

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

Contents

Introduction ..................................................................................................................................... 1

Background ..................................................................................................................................... 2

Safety Issues .................................................................................................................................... 5

Aviation Mishaps and Investigations ........................................................................................ 5

V-22 Mishap Rates, FY2015-FY2024....................................................................................... 7

Selected Fatal V-22 Mishaps Involving Mechanical Failures ................................................... 7

June 8, 2022, Marine Mishap in El Centro, CA .................................................................. 7

November 29, 2023, Air Force Mishap off Yakushima Island, Japan................................. 8

Nacelles ..................................................................................................................................... 9

Proprotor Gearbox (PRGB) ................................................................................................ 9

V-22 Full-Flight Operations Plans ................................................................................................. 10

Selected V-22 Upgrade Plans ...................................................................................................11

V-22 Training and Operational Changes ................................................................................. 12

Tilt-Rotor Lessons Learned ........................................................................................................... 13

Legislative Activity ....................................................................................................................... 14

FY2025.................................................................................................................................... 14

Summary of Congressional Action on FY2025 Funding Request .................................... 14

FY2025 National Defense Authorization Act (H.R. 8070; S. 4638; H.R. 5009;

P.L. 118-159).................................................................................................................. 15

FY2025 DOD Appropriations Act (H.R. 8774; S. 4921; P.L. 119-4, Division A,

Title IV) ......................................................................................................................... 16

FY2026.................................................................................................................................... 16

Summary of Congressional Action on FY2026 Funding Request .................................... 16

Proposals for FY2026 National Defense Authorization Act (H.R. 3838; S. 2296)........... 17

Proposals for FY2026 DOD Appropriations Act (H.R. 4016; S. 2572) ............................ 18

Potential Considerations for Congress .......................................................................................... 18

Size of V-22 Fleets .................................................................................................................. 18

Aircraft Carrier Logistics ........................................................................................................ 19

Funding for Future Upgrades .................................................................................................. 20

Safety Investigation Reports ................................................................................................... 20

Maintenance Training.............................................................................................................. 20

Figures

Figure 1. Selected V-22 Osprey Dimensions ................................................................................... 5

Figure 2. Proprotor Gearbox Schematic .......................................................................................... 9

Tables

Table 1. Selected V-22 Specifications ............................................................................................. 4

Table 2. Congressional Action on FY2025 Funding Request for Selected V-22 Line Items......... 14

Table 3. Congressional Action on FY2026 Funding Request for Selected V-22 Line Items......... 17

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Table A-1. Selected Marine Corps and Air Force Class A Flight Mishaps and Mishap

Rates, FY2015-FY2024 ............................................................................................................. 22

Table A-2. Number of Fatalities Due to V-22 Mishaps ................................................................. 22

Appendixes

Appendix. Safety Statistics ............................................................................................................ 22

Contacts

Author Information........................................................................................................................ 22

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V-22 Osprey: Background and Issues for Congress

Introduction

This report provides background information and potential issues for Congress about the U.S.

Department of Defense (DOD) V-22 Osprey, a joint-service, multi-mission, medium-lift

rotorcraft. The Osprey is produced in three variants, one each for the Marine Corps, Air Force,

and Navy. DOD began developing the V-22 in the 1980s to replace the CH-46 and CH-53 cargo

helicopters. The V-22 experienced delays and fatal accidents during development and was not

declared operational until 2007.1 Since then, the Marine Corps has deployed the V-22 to Iraq,

Afghanistan, and elsewhere. Some military officials have said the aircraft’s unique design

expanded the fleet’s logistics range (i.e., a spectrum between self-sufficient forces and those that

depend on outside resources) 3.5 times beyond its predecessor aircraft.2

As of July 2025, 65 people have died in mishaps involving V-22 aircraft.3 Since 2022, V-22s have

experienced four fatal mishaps4 that killed 20 servicemembers and injured another 20.5 According

to accident investigation reports, component failures within the V-22 drive system caused two of

those crashes.6 After the mishaps, the Navy temporarily halted V-22 operations before reinstating

them in 2024 with a restriction that the craft remain within 30 minutes of a landing site.7 The

Navy and Air Force fleets remain restricted to that limit, which may not be lifted until 2026.8

Some Members of Congress have expressed interest in the safety of the aircraft, particularly

hardware failures; how flying restrictions on the aircraft have affected training and operations of

U.S. forces; and to what extent lessons learned from developing and operating the V-22 are

informing an Army effort to develop a similar type of aircraft, called the Future Long-Range

Assault Aircraft (FLRAA).

1 Department of the Navy, U.S. Navy, U.S. Naval Air Systems Command (NAVAIR), MV-22B Osprey website,

updated February 2023, https://www.navair.navy.mil/product/MV-22B-Osprey; and archived CRS Report RL31384, V22 Osprey Tilt-Rotor Aircraft Program.

2 Lieutenant Colonel (ret.) Douglas Thumm, “I Commanded a Marine V-22 Squadron. Here’s What I Learned,”

Military Times, March 13, 2024, https://www.militarytimes.com/opinion/2024/03/13/i-commanded-a-marine-v-22squadron-heres-what-i-learned/.

3 Flight Safety Foundation, Aviation Safety Network Database, Bell-Boeing V-22 Osprey, accessed on July 1, 2025,

https://asn.flightsafety.org/asndb/type/V22. Marine Corps data provided by Marine Corps Legislative Liaison, July 14,

2025. Air Force data provided by Air Force Legislative Liaison, January 7, 2025.

4 According to DOD Instruction 6055.07, “Mishap Notification, Investigation, Reporting, and Record Keeping,” June

6, 2011, updated June 11, 2019, an aviation mishap is “a DoD mishap involving aircraft or flying operations.” Mishaps

are classified by level of severity. The most serious mishaps are “Class A” mishaps that resulted in death, total

disability, damage equal to or greater than $2 million, or resulted in a destroyed aircraft.

5 Marine Corps data provided by Marine Corps Legislative Liaison, December 12, 2024; Air Force data provided by

Air Force Legislative Liaison, January 7, 2025. The Navy Legislative Liaison confirmed on April 21, 2025, that Navy

MCV-22s had not experienced any fatal mishaps.

6 Department of the Navy, U.S. Marine Corps, “Command Investigation Into the Class A Aviation Mishap that

Occurred on 8 June 2022 in the R-2512 Range Complex,” March 23, 2023, https://www.hqmc.marines.mil/Portals/61/

Docs/FOIA/

Class%20A%20Aviation%20%20Mishap%20R_2512%20Range%20CI_8%20Jun%2022_1%20of%204.pdf?ver=

pSp7_xjQyoGl_sKVQtaS3A%3d%3d; and Brigadier General Michael E. Conley, “United States Aircraft Accident

Investigation Board Report, CV-22B T/N 10-0054, Date of Accident: November 29, 2023,” Air Force Special

Operations Command, https://www.afjag.af.mil/LinkClick.aspx?fileticket=ENTTeS2T9go%3d&portalid=77.

7 Michael Marrow and Valerie Insinna, “V-22 Ospreys Barred From Full Mission Capability Until ‘Mid-2025’:

NAVAIR Boss,” Breaking Defense, June 12, 2024, https://breakingdefense.com/2024/06/v-22-ospreys-barred-fromfull-mission-capability-until-mid-2025-navair-boss/.

8 Michael Marrow, “V-22 Will Fly With Restrictions Until 2026,” Breaking Defense, April 30, 2025,

https://breakingdefense.com/2025/04/v-22-will-fly-with-restrictions-until-2026/.

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V-22 Osprey: Background and Issues for Congress

This report discusses 2022 and 2023 mishaps, the services’ plans to modernize the V-22 and

determine it ready for full flight operations, and design differences between the V-22 and the

FLRAA.9 The report also addresses certain legislative activity and issues that Congress may

consider. The Appendix provides tables listing V-22 safety statistics during the 10-year period

2015-2024 and figures on fatal V-22 mishaps.

Background

The V-22 is a type of aircraft known as a tilt-rotor, which is a unique design for a crewed military

aircraft (see Figure 1). Along with the speed and range of propeller-driven forward flight, a tiltrotor has the ability to take off and land without a runway or from the deck of a ship, similar to a

helicopter. The V-22 has an additional feature for maritime use: its wings can rotate and fold

horizontally to be transported and stored more easily on an aircraft carrier or assault ship.10

The V-22 is produced by a joint venture of Bell Helicopter Textron of Fort Worth, TX, and

Boeing Helicopters of Philadelphia, PA, called Bell-Boeing.11 The Department of the Navy’s

Naval Air Systems Command (NAVAIR) manages the V-22 Joint Program Office (JPO) for the

development, support, fielding, and disposal of the three types of V-22.

Formal development of the V-22 began in the 1980s. During development, the platform

experienced mishaps, including one caused by engine failure that killed all seven crew

members.12 As of July 2025, 65 military personnel have died in mishaps involving V-22 aircraft.13

The first V-22 reached initial operational capability in 2007.14 DOD plans for production of the

aircraft to end in 2028.15 The procurement total includes 360 V-22s for the Marines, 56 for Air

Force Special Operations Command (AFSOC), and 53 for the Navy.16 Japan has received 17 V22s.17 DOD in December 2019 estimated the total V-22 acquisition cost at $55.7 billion.18

9 For more information, see CRS In Focus IF12771, Future Long-Range Assault Aircraft (FLRAA), by Jennifer

DiMascio.

10 Boeing, “22 Fast Facts on the Bell Boeing V-22 Osprey,” June 20, 2023, https://www.boeing.com/features/2023/06/

22-fast-facts-on-the-bell-boeing-v-22-osprey.

11 NAVAIR, MV-22B Osprey website.

12 Charles Doe, “V-22 Osprey Crash Blamed on Engine Failure,” United Press International, September 29, 1992,

https://www.upi.com/Archives/1992/09/29/V-22-Osprey-crash-blamed-on-engine-failure/4228717739200/.

13 Flight Safety Foundation, Aviation Safety Network Database, Bell-Boeing V-22 Osprey, accessed on July 1, 2025,

https://asn.flightsafety.org/asndb/type/V22. Marine Corps data provided by Marine Corps Legislative Liaison, July 14,

2025. Air Force data provided by Air Force Legislative Liaison, January 7, 2025.

14 NAVAIR, MV-22B Osprey website.

15 Based on CRS email correspondence with NAVAIR, PMA-275, October 3, 2024.

16 Based on CRS email correspondence with Marine Corps officials, February 13, 2025. According to budget

documents, Congress in FY2024 authorized the purchase of five CMV-22s more than the program of record.

https://www.secnav.navy.mil/fmc/fmb/Documents/26pres/APN_BA1-4_Book.pdf.

17 Colonel [Brian] Taylor, “V-22 Program Overview,” V-22 Joint Program Office, April 30, 2024, p. 3, archived at

https://web.archive.org/web/20241008122301/https://www.marcorsyscom.marines.mil/Portals/105/

001_MDM%202024_NAVAIR_PMA%20275.pdf.

18 U.S. Department of Defense (DOD), Washington Headquarters Services, Freedom of Information Act Reading

Room, Selected Acquisition Reports (SARs), 2019 SARs, V-22 Osprey Joint Services Advanced Vertical Lift Aircraft

(V-22), https://www.esd.whs.mil/Portals/54/Documents/FOID/Reading%20Room/Selected_Acquisition_Reports/

FY_2019_SARS/20-F-0568_DOC_81_V-22_SAR_Dec_2019.pdf.

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V-22 Osprey: Background and Issues for Congress

The Marine Corps version of the V-22—called the MV-22—carries 24 combat troops and was

developed to replace the medium-lift CH-46 and heavy-lift CH-53 helicopters.19 The MV-22 is

designed for amphibious assault, combat support, and medium-lift combat service support

missions.20 The Marine Corps had an inventory of 306 MV-22s, as of June 2024.21 MV-22s are

also a part of Marine Helicopter Squadron One (HMX-1), which supports presidential transport,

carrying support personnel, media, and material. 22 (The President and Vice President fly in a

separate helicopter called the VH-92 Patriot.23)

AFSOC operates a variant of the V-22 called the CV-22. The command uses CV-22s to execute

long-range infiltration, exfiltration, and resupply missions. Those missions tend to take place in

environments that Air Force officials have described as “challenging” and that expose the aircraft

to dust and austere landings.24 The Air Force, which has operated the CV-22 since 2009, has an

inventory of 51 of these aircraft.25 The CV-22 carries up to 32 personnel.26

The Navy’s V-22 variant is called the CMV-22, which is intended to transport personnel, mail,

and priority cargo from advance bases to aircraft carriers, even while under threat.27 The Navy

redesigned the forward sponson fuel tanks and added fuel tanks on the wings so that the aircraft

can carry 25% more fuel than the Marine Corps’ MV-22 variant.28 According to an announcement

from the Navy, the CMV-22 can haul up to 6,000 pounds over 1,150 nautical miles.29 The Navy

also announced that the CMV-22 variant reached initial operating capability in February 2022.30

The Navy has 37 CMV-22s, a platform intended to replace 15 aging C-2 Greyhounds, a fixed-

19 U.S. Marine Corps, Tilt Rotor Aircraft website, https://www.aviation.marines.mil/About/Aircraft/Tilt-Rotor/

#:~:text=It%20will%20replace%20the%20Corps,CH%2D53D%20medium%20lift%20helicopters.

20 U.S. Marine Corps, Tilt Rotor Aircraft website, https://www.aviation.marines.mil/About/Aircraft/Tilt-Rotor/

#:~:text=It%20will%20replace%20the%20Corps,CH%2D53D%20medium%20lift%20helicopters.

21 Written testimony of Vice Admiral Carl Chebi, Commander, Naval Air Systems Command and Gary Kurtz, Program

Executive Officer, Air Anti-Submarine Warfare and Special Missions Programs, DOD, for U.S. Congress, House

Committee on Oversight and Accountability, Subcommittee on National Security, the Border, and Foreign Affairs,

Addressing Oversight and Safety Concerns in the Department of Defense’s V-22 Osprey Program, hearings, 118th

Cong., 2nd sess., June 12, 2024, https://oversight.house.gov/wp-content/uploads/2024/06/Chebi_Kurtz-WrittenTestimony.pdf. Figure is most recently reported inventory information.

22 Chris Riback, “V-22 Gets Presidential Treatment,” Roll Call, March 23, 2015, https://rollcall.com/2015/03/23/v-22gets-presidential-treatment/.

23 NAVAIR, VH-92 Patriot website, https://www.navair.navy.mil/product/VH-92A-Patriot.

24 Based on CRS communications with Air Force officials, December 5, 2024.

25 Testimony of Vice Admiral Carl Chebi, Commander, Naval Air Systems Command and Gary Kurtz, Program

Executive Officer, Air Anti-Submarine Warfare and Special Missions Programs, DOD, in U.S. Congress, House

Committee on Oversight and Accountability, Subcommittee on National Security, the Border, and Foreign Affairs,

Addressing Oversight and Safety Concerns in the Department of Defense’s V-22 Osprey Program, hearings, 118th

Cong., 2nd sess., June 12, 2024, H.Hrg. 118-115, https://www.govinfo.gov/content/pkg/CHRG-118hhrg56063/pdf/

CHRG-118hhrg56063.pdf.

26 Department of the Air Force, CV-22 Osprey fact sheet, https://www.af.mil/About-Us/Fact-Sheets/Display/Article/

104531/.

27 Robbin Laird, “Why Adding the Osprey to the Atlantic Naval Air Force Matters,” Breaking Defense, December 2,

2024, https://breakingdefense.com/2024/12/why-adding-the-osprey-to-the-atlantic-naval-air-force-matters/.

28 Based on CRS email correspondence with Marine Corps officials, February 13, 2025.

29 Department of the Navy, Naval Air Station Patuxent River Public Affairs, “Navy’s V-22 Achieves Initial Operational

Capability Designation,” press release, February 18, 2022, https://www.navy.mil/Press-Office/News-Stories/Article/

2940299/navys-v-22-achieves-initial-operational-capability-designation/#:~:text=

%E2%80%9CThis%20aircraft%20went%20from%20first,operational%20capability%20expected%20in%202023.

30 NAVAIR, “Navy’s V-22 Achieves Initial Operational Capability Designation.”

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V-22 Osprey: Background and Issues for Congress

wing aircraft that currently conducts carrier onboard delivery (COD) missions. 31 The Navy has

indicated that it plans to retire the remaining Greyhounds by 2026; it has continued to use the C2s while the Navy’s CMV-22s are under flight restrictions.32

Table 1. Selected V-22 Specifications

Propulsion

2 Rolls-Royce AE1107C engines

Maximum Vertical Takeoff Weight

52,600 pounds

Fuel Capacity

1,721-2,025 gallons

Maximum Cruise Speed

255 knots

Service Ceiling

25,000 feet

Source: Department of the Navy, U.S. Marine Corps, V-22 Osprey Guidebook, https://www.mcipac.marines.mil/

Portals/28/Documents/MV22Guidebook.pdf; and NAVAIR, CMV-22 Osprey website,

https://www.navair.navy.mil/product/CMV-22B-Osprey.

31 Chebi, Testimony in H.Hrg. 118-115; and NAVAIR, CMV-22B Osprey website, https://www.navair.navy.mil/

product/CMV-22B-Osprey. Number of CMV-22s current as of February 13, 2024, per program office officials.

32 Sam LaGrone, “Navy Surging C-2A Greyhounds as V-22 Groundings Continue,” USNI News, February 13, 2024,

https://news.usni.org/2024/02/13/navy-surging-c-2a-greyhounds-as-v-22-groundings-continue.

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Figure 1. Selected V-22 Osprey Dimensions

Source: Shutterstock-Pixelsquid/Shutterstock.com; and Department of the Navy, U.S. Marine Corps, V-22

Osprey Guidebook.

Safety Issues

As previously noted, and as of July 2025, 65 people have died in mishaps involving V-22 aircraft,

which includes 30 fatalities before 2007, when the aircraft was declared ready for operations, and

35 after 2007. Of the 35 fatalities since 2007, 23 occurred in Marine Corps aircraft and 12 in Air

Force aircraft.33

Aviation Mishaps and Investigations

DOD characterizes an aviation mishap in the flight subcategory as a situation “where there is

intent for flight and damage to DOD aircraft.”34 Within DOD, the military departments conduct

33 Flight Safety Foundation, Aviation Safety Network Database, Bell-Boeing V-22 Osprey, accessed on July 1, 2025,

https://asn.flightsafety.org/asndb/type/V22. Marine Corps data provided by Marine Corps Legislative Liaison, July 14,

2025. Air Force data provided by Air Force Legislative Liaison, January 7, 2025.

34 DOD Instruction 6055.07, “Mishap Notification, Investigation, Reporting, and Record Keeping,” June 6, 2011,

updated June 11, 2019, p. 29, https://www.esd.whs.mil/Portals/54/Documents/DD/issuances/dodi/605507p.pdf.

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V-22 Osprey: Background and Issues for Congress

investigations into aviation mishaps under their purview. For example, within the Department of

the Air Force, the Air Force Safety Center (AFSEC) oversees mishap investigations for the Air

Force and Space Force.35

After a mishap takes place, AFSEC appoints an Interim Safety Board to begin an investigation

and assigns the mishap a class. DOD defines a Class A mishap, the most serious type, as an

incident in which “the resulting total cost of damages to Government and other property is $2

million or more, a DOD aircraft is destroyed (excluding UAS [Unmanned Aerial Systems]

Groups 1, 2, or 3), or an injury or occupational illness results in a fatality or permanent total

disability.”36

Next, a Safety Investigation Board takes place to discover the root cause of the mishap.

According to DOD, the purpose of safety investigations is to prevent future mishaps. Safety

investigation reports produce findings and recommendations for future action. The

recommendations and much of the information contained in the documents may be privileged

(i.e., legally protected and not for public release). According to DOD, the term “safety privilege”

describes “privileges recognized by the courts that protect safety information from release. It is an

executive privilege afforded a head of an agency to protect information from release that would

hamper the efficient operation of an important Government program and perhaps impair the

national defense or security.”37 DOD describes some exceptions to the privilege. One exception is

a 1989 agreement between DOD and the House Armed Services Committee (HASC) that allows

the chair or the ranking member of the HASC or Senate Armed Services Committee (SASC) to

arrange a briefing about safety information.38 The DOD instruction further states that

[t]he Chairman and Ranking Minority Member may review the requested portions of the

privileged safety report during the briefing, but they may not be provided with advance

copies, nor will the Chairman and Ranking Minority Member release any privileged safety

information to the public, other Government agencies, or other members of the Congress

or staff.39

The Air Force may also convene an Accident Investigation Board to conduct a concurrent

investigation. The resulting reports differ from Safety Investigation Board reports in that accident

investigations may be publicly released, as they are conducted as a legal investigation and do not

offer recommendations.40 The Navy and Marine Corps also may convene Aviation Mishap

Boards, the results of which may be privileged.41 The Navy’s Judge Advocate General may also

conduct a command investigation, and like the Air Force Accident Investigation Board, the results

of that investigation may be disclosed under the Freedom of Information Act.42

35 Department of the Air Force, Air Force Safety Center, https://www.af.mil/About-Us/Fact-Sheets/Display/Article/

104488/air-force-safety-center/.

36 DOD Instruction 6055.07.

37 DOD Instruction 6055.07.

38 DOD Instruction 6055.07.

39 DOD Instruction 6055.07.

40 Department of the Air Force, Air Force Safety Center, Mishap Investigation Process website,

https://www.safety.af.mil/Home/Mishap-Investigation-Process/; Department of the Air Force, Air Force Instruction 51307, Aerospace and Ground Accident Investigations, March 18, 2019, https://static.e-publishing.af.mil/production/1/

af_ja/publication/afi51-307/afi51-307.pdf.

41 Department of the Navy, Naval Safety Command, “Mishap Investigations,” https://navalsafetycommand.navy.mil/

Reporting-Investigations/Mishap-Investigations/.

42 Department of the Navy, Navy Judge Advocate General’s (JAG) Corps, Naval Justice School, JAGMAN

Investigations Handbook, archived at https://apps.dtic.mil/sti/tr/pdf/AD1014458.pdf.

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V-22 Osprey: Background and Issues for Congress

V-22 Mishap Rates, FY2015-FY2024

DOD tracks aircraft mishaps per 100,000 hours of flight. The Class A mishap rate for the Marine

Corps’ MV-22B aircraft is 2.56 mishaps per 100,000 flight hours for FY2015 to FY2024.43 The

Marine Corps’ average for all aircraft over that time frame is 2.67 mishaps per 100,000 flight

hours.44 The Air Force’s Class A mishap rate for CV-22 aircraft over the same time frame is 11.55

mishaps per 100,000 flight hours, compared with the Air Force average for its entire fleet of

aircraft of 1.65 mishaps per 100,000 flight hours.45 According to the Navy, its CMV-22s have not

experienced any mishaps or fatalities.46

For more information on certain military aircraft mishap rates, see Table A-1.

Selected Fatal V-22 Mishaps Involving Mechanical Failures

This section discusses two fatal mishaps, one in 2022 and one in 2023 that

•

are among the most recent fatal incidents,

are the most recent mishaps caused by mechanical failures, and

are mishaps about which some Members of Congress have expressed an interest

in potential material solutions.

June 8, 2022, Marine Mishap in El Centro, CA

According to the Judge Adjutant General command investigation report on the Class A mishap on

June 8, 2022, five Marines from the 3rd Marine Aircraft Wing died during a training flight in El

Centro, CA.47 After departure, one pilot asked to change the landing location to cool rising

gearbox temperatures. The crew completed refueling operations at Lake Havasu City Municipal

Airport at 11:50 a.m. and then flew on to Yuma Range. The crew proceeded to the training

location and were flying in a pattern, conducting live-fire testing. The aircraft conducted three

ordnance delivery legs without incident. During the fourth, a crew member reported “indications

of ‘hot boxes,’” and the aircraft was granted permission to move to an overhead flight position to

cool the gearbox—the second time that day the gearbox temperatures were reported rising. Within

two minutes, the aircraft lost radar contact and hit the ground. “The mishap was caused by a dual

HCE [hard clutch engagement] event that created a Single Engine/ICDS [Interconnect Drive

System] failure compound emergency leading to an unrecoverable low altitude departure from

controlled flight and rapid rate of descent.”48

The report further states that “although the root cause of HCE remains unknown, incident trend

analysis shows that HCE events have occurred in aircraft with input quills flown more than 800

43 Based on CRS correspondence with Marine Corps Legislative Liaison for Class A Mishap data, December 12, 2024.

44 Based on CRS correspondence with Marine Corps Legislative Liaison for Class A Mishap data, December 12, 2024.

45 Based on CRS correspondence with Air Force Legislative Liaison for Class A Mishap data, January 7, 2025; and

https://www.safety.af.mil/Portals/71/documents/Aviation/Mishap%20Summaries/USAF_Aviation_Class_A_SummaryCopy.pdf, p. 2.

46 Based on CRS correspondence with Office of Navy Legislative Affairs, April 21, 2025.

47 U.S. Marine Corps, “Command Investigation Into the Class A Aviation Mishap that Occurred on 8 June 2022 in the

R-2512 Range Complex.”

48 U.S. Marine Corps, “Command Investigation Into the Class A Aviation Mishap that Occurred on 8 June 2022 in the

R-2512 Range Complex.”

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

hours.”49 The input quill assemblies in this aircraft had flown more 800 hours.50 Vice Admiral

Carl Chebi, who leads Naval Air Systems Command, which runs the V-22 Joint Program Office,

told the House Committee on Government Oversight that the program has experienced 19 “hard

clutch events,” and that in 2022, a sharp increase in the number had occurred.51 “Over time the

clutch wears out and has a higher susceptibility to slipping which will cause a hard clutch event,”

Chebi said. Based on the data, Chebi said he mandated that clutches with more than 800 flight

hours would be replaced.52

November 29, 2023, Air Force Mishap off Yakushima Island, Japan

A mechanical issue caused another Class A mishap in 2023. On November 29, 2023, eight

members of the Air Force’s 21st Special Operations Squadron died when the CV-22B in which

they were flying crashed into waters about a half mile off the coast of Yakushima Island, Japan.53

The crew was taking part in a joint interoperability exercise. According to the Air Force Accident

Investigation Board report, the pilot received a series of “chip burn” alerts, some of which he

disregarded. After receiving a “Land as Soon as Possible” alert, the crew aborted its mission and

diverted to a nearby airport. On final approach to the runway, the voice and data recorder

recorded cascading failures and auditory warnings. The aircraft rolled to the left and landed in the

water.54

According to the accident report, the Accident Investigation Board President “found, by a

preponderance of the evidence, the mishap was caused by a catastrophic failure of the left-hand

Proprotor Gearbox that created a rapidly cascading failure of the [mishap aircraft’s] drive system,

resulting in an instantaneous asymmetric lift condition that was unrecoverable.”55 The Board also

found that the pilot was at fault for failing to divert the flight and land at a different location

earlier.56 The investigation found that the left-hand PRGB had failed and that one of five highspeed pinion gears within the PRGB had fractured.57 The Navy has said it plans to replace the

gearbox components that had experienced corrosion to prevent future defects.58

49 U.S. Marine Corps, “Command Investigation Into the Class A Aviation Mishap that Occurred on 8 June 2022 in the

R-2512 Range Complex.”

50 U.S. Marine Corps, “Command Investigation Into the Class A Aviation Mishap that Occurred on 8 June 2022 in the

R-2512 Range Complex.” The IQA in the left-side proprotor gearbox had flown 2,437 hours—and 1,094 hours since

being repaired. The IQU on the right-side proprotor gearbox had flown 2,007 hours.

CQ Transcripts, “House Oversight and Accountability Subcommittee on National Security, the Border, and Foreign

Affairs Holds Hearing on V-22 Osprey Program Oversight and Safety,” June 12, 2024.

52 CQ Transcripts, “House Oversight and Accountability Subcommittee on National Security, the Border, and Foreign

Affairs Holds Hearing on V-22 Osprey Program Oversight and Safety,” June 12, 2024.

53 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

54 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

55 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

56 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

57 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

58 NAVAIR, PMA-275 written responses to Congressional Research Service V-22 questions for October 3, 2024.

briefing.

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V-22 Osprey: Background and Issues for Congress

Nacelles

The fatal V-22 mishaps that occurred on June 8, 2022, and November 29, 2023, were linked to

mechanical failures that occurred within the nacelles, which are sections located on the edge of

each wing that tilt to enable the aircraft’s transition from rotary-wing lift to propeller-driven

flight. Each nacelle contains an engine, drive system, components, and wiring. The nacelles

endure vibration from the engine, and dirt, dust, and engine oil can collect on the wires in the

nacelles. Prime contractor Bell Textron said in 2021 that 60% of the V-22’s maintenance hours

are spent on nacelle work.59

Proprotor Gearbox (PRGB)60

In particular, investigators found that different types of mechanical failures in a nacelle

component called the proprotor gearbox (PRGB) were factors in the fatal V-22 mishaps that

occurred on June 8, 2022, and November 29, 2023. Part of the V-22’s drive system, located

within each nacelle, is a PRGB (see Figure 2). The engine provides power to an input quill,

which attaches to the clutch assembly. The clutch assembly provides power through a system of

interlocking gears and pinions to turn the mast, which drives the corresponding proprotor. The

PRGB has magnetic plugs and screens to capture debris, as well as a system of three detectors to

send the pilot a “chip burn” alert if debris is detected in the gear oil.61 Press reports indicate that

DOD has reported 60 incidents with V-22 proprotor gearboxes over the past five years and that

the military removed 609 proprotor gearboxes for repair over the past 10 years.62

Figure 2. Proprotor Gearbox Schematic

Source: Brigadier General Michael E. Conley, “United States Aircraft Accident Investigation Board Report, CV22B T/N 10-0054, Date of Accident: November 29, 2023,” Air Force Special Operations Command,

https://www.afjag.af.mil/LinkClick.aspx?fileticket=ENTTeS2T9go%3d&portalid=77.

59 Bell Boeing, “Bell Boeing Begin Nacelle Improvement on Air Force CV-22,” press release, September 23, 2021,

https://news.bellflight.com/en-US/202903-bell-boeing-begin-nacelle-improvement-on-air-force-cv-22.

60 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

61 Based on CRS correspondence with Marine Corps officials, February 13, 2025.

62 Tara Copp and Aaron Kessler, “Weak spots in metal may have led to fatal Osprey crash off Japan, documents

obtained by AP reveal,” Associated Press, August 4, 2024, https://apnews.com/article/osprey-crash-proprotor-japanv22-d0402b8696e9f1da7d0af4bd368c92f0.

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

V-22 Full-Flight Operations Plans

In December 2023, NAVAIR, which leads the V-22 JPO, grounded all V-22 variants, saying that a

preliminary investigation showed a potential material failure had caused the November 29, 2023,

mishap.63 In March 2024, NAVAIR lifted the initial grounding, though it stated in a press release

that “the U.S. Navy, U.S. Marine Corps, and U.S. Air Force will each execute their return to flight

plans according to service specific guidelines.”64 By May 2024, news reports stated that all

variants of the V-22 were still restricted fly within 30 minutes of a suitable divert airfield.65

After a near-crash in New Mexico in November 2024, Vice Admiral Chebi briefly reinstituted the

fleetwide grounding.66 On December 20, 2024, NAVAIR directed inspections verifying the

number of hours on each PRGB prior to the aircraft’s next flight, allowing the aircraft to resume

restricted flights.67

In a July 16, 2024, letter to then-Defense Secretary Lloyd Austin, the chair and ranking member

of the House Committee on Government Oversight, asked for a list of the “date, location, and

cause of every Class A Osprey mishap” since 1991. The letter also asked for safety investigation

reports from all Class A Osprey mishaps since 1991. The committee, which first requested

information from DOD in December 2023, added that it had “encountered significant delays and

hurdles to obtain necessary materials.”68 As of September 2025, it is not clear whether the

department has transmitted the information.

According to testimony from Kurtz and Vice Admiral Chebi, NAVAIR is conducting engineering

testing and analysis to establish criteria for a full unrestricted flight by the V-22. “A return to full

mission capability is not expected to occur before mid-2025,” they wrote.69 The Department of

the Navy, including the V-22 JPO, NAVAIR, and Bell-Boeing, were reviewing further riskreduction efforts.70 In April 2025, Marine Corps officials reportedly said that full-flight operations

would not resume until 2026, to provide time for the service to roll out upgrades to PRGB

components.71 The Marines are also reportedly testing a new input quill assembly to mitigate

hard-clutch engagements.72

63 NAVAIR, “NAVAIR Grounds V-22 Fleet,” press release, December 7, 2023, https://www.navair.navy.mil/news/

NAVAIR-grounds-V-22-fleet/Wed-12062023-1923.

64 NAVAIR, “NAVAIR Returns V-22 Osprey to Flight Status,” press release, March 8, 2024,

https://www.navair.navy.mil/news/NAVAIR-returns-V-22-Osprey-flight-status/Fri-03082024-0553.

65 Aaron Mehta, “V-22 Osprey Operating With ‘Limited Envelope,’ Required to Stay Near Airfields,” Breaking

Defense, May 15, 2024.

66 Tara Copp, “Military Pauses Osprey Flights Again After More Metal Failures are Found in Near-Crash in

November,” Associated Press, December 9, 2024.

67 NAVAIR, “NAVAIR Issues V-22 Bulletin and Interim Flight Clearance,” press release, December 19, 2024,

https://www.navair.navy.mil/news/NAVAIR-Issues-V-22-Bulletin-and-Interim-Flight-Clearance/Thu-12192024-1121.

68 Letter from James Comer, Chair, House Committee on Government Oversight and Accountability, and Glenn

Grothman, Chair, Subcommittee on National Security, the Border, and Foreign Affairs, to Lloyd Austin, Secretary of

Defense Lloyd Austin, July 16, 2024, https://oversight.house.gov/wp-content/uploads/2024/07/Osprey-Follow-UpLetter13.pdf.

69 Chebi and Kurtz, Testimony in H.Hrg. 118-115.

70 Chebi and Kurtz, Testimony in H.Hrg. 118-115.

71 Michael Marrow, “V-22 Will Fly With Restrictions Until 2026,” Breaking Defense, April 30, 2025,

https://breakingdefense.com/2025/04/v-22-will-fly-with-restrictions-until-2026/.

72 Marrow, “V-22 Will Fly With Restrictions Until 2026.”

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V-22 Osprey: Background and Issues for Congress

Selected V-22 Upgrade Plans

DOD has initiated or proposed various maintenance and upgrade programs to improve the V-22

and its drive system. Upgrade efforts include the following:

Proprotor Gearbox Improvements. According to NAVAIR, the design and qualification

program is complete, and hardware for hardened PRGB planetary pinion bearings was to start

delivery in August 2024 to address a “reliability shortfall.”73 In October 2024, NAVAIR said it

planned to replace some PRGB components—including high-speed planetary pinion gears, lowspeed planetary pinion gears, bull gears, and sun gears—with a more durable alloy known as X53 triple-melt alloy to stop inclusions, or unwanted particles, in the metal (see Figure 2).74

According to the Federal Aviation Administration, the triple-melt refers to a manufacturing

process for nickel-based alloys that has reduced anomalies and are recommended for use in

rotating components.75 In February 2025, the Navy said it would conduct a triple-melt process on

all gears made from double-melt X-53.76 The Navy has said the parts are planned to be available

to the fleet by May 2025. To prevent current flaking of cadmium plating on the upper PRGB

mast, the Navy said it planned to add zinc nickel plating to the PRGB mast beginning in 2025.77

PRGB Input Quill/Clutch Upgrade. As discussed above, the PRGB clutch can disengage and

reengage, resulting in a hard-clutch engagement.78 The Navy has mandated that all clutches that

had flown more than 800 hours be replaced. In January 2023, Bell-Boeing received a $12.7

million contract to engineer the integration, qualification, documentation, and testing for a

proprotor gearbox input quill and clutch design for all variants of the V-22.79 In addition, the

Navy said it may select a redesign of the input quill assembly and provide data for a follow-on

contract beginning in 2026.80

Nacelle Improvement Plan. Naval Air Systems Command awarded Bell-Boeing contracts to

develop, design, and install nacelle modification kits for the Air Force’s CV-22.81 The

modification provides better access to the nacelle’s insides and streamlines the wiring, which

helps maintenance personnel diagnose and troubleshoot potential issues with the drive system.82

In the National Defense Authorization Act for Fiscal Year 2024 (NDAA; P.L. 118-31, §125),

Congress directed DOD to upgrade “not fewer than 24 V-22s” under the nacelle improvement

program.

Osprey Drive System Safety and Health Information (ODSSHI). ODSSHI is a diagnostic

system designed to monitor gearbox vibration and estimate the length of time before a gearbox

73 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024.

74 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024.

75 U.S. Department of Transportation, Federal Aviation Administration, Advisory Circular 33.15-2, “Manufacturing

Processes for Premium Quality Nickel Alloy for Engine Rotating Parts,” https://www.faa.gov/documentLibrary/media/

Advisory_Circular/AC_33_15-2.pdf. According to the document, “Improvements in all stages of melt, remelt, and

conversion have resulted in a significant reduction in the occurrence of melt-related defects since the mid-1980s.”

76 Based on CRS correspondence with Marine Corps officials, February 13, 2025.

77 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024.

78 CQ Transcripts, “House Oversight and Accountability Subcommittee on National Security, the Border, and Foreign

Affairs Holds Hearing on V-22 Osprey Program Oversight and Safety,” June 12, 2024.

79 DOD, Contracts, January 20, 2023 (awarded January 18, 2023), https://www.defense.gov/News/Contracts/Contract/

Article/3273802/.

80 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024.

81 NAVAIR, “V-22 Contract Award Kicks Off Major Nacelle Redesign Effort,” January 27, 2021,

https://www.navair.navy.mil/news/V-22-contract-award-kicks-major-nacelle-redesign-effort/Wed-01272021-1400.

82 Based on CRS communications with Air Force officials, December 5, 2024.

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

requires replacement.83 Bell-Boeing was awarded a $53.6 million contract in March 2023 to

engineer a V-22 Gearbox Vibration Monitoring/Osprey Drive System safety and health

information system to detect degrading gearbox components.84

V-22 Cockpit Technology Refresh (VeCToR). VeCToR is a proposed comprehensive

modernization of the aircraft’s avionics systems, addressing parts obsolescence and upgrading the

flight-control system to improve controls during “brownout” situations, which occur when wind

created by rotor blades stir up a blinding amount of dust. DOD initiated a trade study and analysis

of alternatives in the third quarter of FY2024 to define requirements. The initial phase of the

VeCToR trade study was scheduled to end in the second quarter of FY2025 and inform any

follow-on VeCToR upgrade plans.85

Renewed V-22 Aircraft Modernization Program (ReVAMP). ReVAMP is a proposed mid-life

upgrade designed to allow the Marine Corps continue to operate the MV-22 until 2055. According

to the Navy, elements of ReVAMP may include improved drive systems and nacelles, ice

protection, and new or re-cored engines.86 In the fourth quarter of FY2024, the V-22 program

office initiated a trade study and analysis of alternatives to define requirements, which is

scheduled to end in the first quarter of FY2026.87

V-22 Training and Operational Changes

While mechanical failures were factors in the fatal V-22 mishaps that occurred on June 8, 2022,

and November 29, 2023, the Accident Investigation Board report for the latter noted that pilot

error was also a contributing factor.88 (The Command Investigation into the June 2022 mishap

near El Centro, CA, said human factors were not a factor in the mishap and that pilot and aircrew

preparation were appropriate.)89 Accident investigations determined that that pilot error had

caused two other fatal mishaps during the 2022-2023 timeframe—one in Australia and one in

Norway.90

In addition to seeking to address the mechanical failures, DOD has implemented controls to

improve flight safety. In testimony to the House Government Oversight Committee, Vice Admiral

Chebi and Gary Kurtz, the DOD Program Executive Officer for Air Anti-Submarine Warfare and

Special Missions Programs, wrote that some of those controls include NAVAIR briefings about

mishap causal factors and reviews and serial-number verification of “safety critical life-limited

components.”91 They also testified that program officials plan to verify on the ground that the V83 Based on CRS communications with officials from Bell Textron, November 21, 2024.

DOD, Contracts for March 8, 2023, Navy contracts, https://www.defense.gov/News/Contracts/Contract/Article/

3323211/.

85 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024; and Taylor, “V-22 Program Overview,”

V-22 Joint Program Office, p. 6.

86 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024; and Taylor, “V-22 Program Overview,”

V-22 Joint Program Office, p. 6.

87 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024.

88 Conley, “United States Aircraft Accident Investigation Board Report, CV-22B T/N 10-0054, Date of Accident:

November 29, 2023.”

89 U.S. Marine Corps, “Command Investigation Into the Class A Aviation Mishap that Occurred on 8 June 2022 in the

R-2512 Range Complex.”

90 U.S. Marine Corps, “Command Investigation into the Facts and Circumstances Surrounding the Class A Aviation

Mishap of an MV-22B of Marine Medium Tiltrotor Squadron 363 (Reinforced) on 27 August 2023 in Australia,” May

4, 2024; and U.S. Marine Corps, “Command Investigation into the MV-22 Aviation Mishap that Occurred on 18 March

2022 During Exercise Cold Response,” June 29, 2022.

91 Chebi and Kurtz, Testimony in H.Hrg. 118-115.

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

22 drive train is operating properly before a flight, improve mission planning, and modify

emergency procedures.92

In March 2024, the Marine Corps in a press release indicated it was taking a “three-phased

approach” to returning 17 MV-22 squadrons to flight.93 First, the Marines would provide care and

basic skills training for pilots and aircrew. Second, squadrons were to follow training and

readiness manuals for basic and advanced proficiency. Third, the squadrons were to conduct predeployment, mission-specific training for any next deployment.

Also in March 2024, the Navy in a press release stated it was implementing “a deliberate, multiphased, conditions-based approach that will prioritize safety during the CMV-22 return to

flight.”94 That plan includes maintenance checks and tailored training.95 The Navy changed its

instructions for operations so that pilots would no longer disregard the V-22’s on-board alert

system.96

The Air Force has said it made similar operational modifications. “Our criteria prior was threechip [warnings] was a ‘land as soon as practical,’” Air Force Special Operations Command

Commander Lieutenant General Michael E. Conley reportedly stated in September 2024.97

“We’ve changed that to one, and then two becomes a ‘land as soon as possible.’ At the end of the

day, there will always be aircraft commander and crew discretion.”98

Air Force Special Operations Command stated in a press release that it is also implementing a

three-phase plan to return CV-22s to full flight operations.99 The first phase contains ground and

simulator training, safety briefings, a review of maintenance records, and refined squadron

training with new safety protocols.100 The second, multi-month phase includes basic training and

training for full mission proficiency, as well as additional maintenance training and squadronlevel training.101 The third phase includes a resumption of full mission profiles, with multilateral

exercises, and operational deployments.102

Tilt-Rotor Lessons Learned

The Army is seeking a next-generation rotorcraft with more speed and greater range than the prior

types of helicopters and has chosen to develop a tilt-rotor design similar to the V-22 from Bell

92 Chebi and Kurtz, Testimony in H.Hrg. 118-115.

93 U.S. Marine Corps, “Marine Corps Returns MV-22 to Flight Status,” press release, March 8, 2024,

https://www.marines.mil/News/Press-Releases/Press-Release-Display/Article/3700548/marine-corps-returns-mv-22-toflight-status/.

94 U.S. Navy, “Navy Announces CMV-22 Return to Flight Status.”

95 U.S. Navy, “Navy Announces CMV-22 Return to Flight Status.”

96 Mallory Shellbourne, “Navy, Marines Learning to Make Do as V-22 Restrictions Endure,” USNI News, February 11,

2025, https://news.usni.org/2025/02/11/navy-marines-learning-to-make-do-as-v-22-restrictions-endure.

97 Greg Hadley, “AFSOC Will Deploy Ospreys in ‘Weeks,’ But Full Fleet Readiness is Still Months Away,” Air &

Space Forces Magazine, September 18, 2024, https://www.airandspaceforces.com/afsoc-boss-osprey-deploy-weeks/.

98 Hadley, “AFSOC Will Deploy Ospreys in ‘Weeks,’ But Full Fleet Readiness is Still Months Away.”

99 Department of the Air Force, U.S. Air Force, Air Force Special Operations Command (AFSOC) Public Affairs,

“AFSOC to Resume CV-22 Flight Operations,” press release, March 8, 2024, https://www.afsoc.af.mil/News/ArticleDisplay/Article/3700599/afsoc-to-resume-cv-22-flight-operations/.

100

AFSOC Public Affairs, “AFSOC to Resume CV-22 Flight Operations.”

101 AFSOC Public Affairs, “AFSOC to Resume CV-22 Flight Operations.”

102 AFSOC Public Affairs, “AFSOC to Resume CV-22 Flight Operations.”

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V-22 Osprey: Background and Issues for Congress

Textron. Army officials say they intend the aircraft, called the Future Long-Range Assault

Aircraft (FLRAA), to replace the Sikorsky UH-60 Black Hawk helicopter.103

Although the current FLRAA design is similar to the V-22 in that it is a tilt-rotor, FLRAA differs

from that of the V-22 in several noteworthy ways. The V-22 is larger than FLRAA.104 The V-22’s

entire nacelle, containing the engine, rotates; on the FLRAA design, only the rotor blades tip

forward. Officials from Bell state they have further simplified the nacelle design, using digital

tools not available when the current design was created.105 Technological advancements also

potentially enable a less complex wiring system for FLRAA, with wires that are coated and

intended to be easier to maintain. Company officials say that the FLRAA clutch is more

conventional and akin to other models of helicopter than the V-22’s clutch.106 The current FLRAA

prototype design reportedly has a straight wing, which eliminates the need for a mid-wing

gearbox like on the V-22.107

Legislative Activity

FY2025

Summary of Congressional Action on FY2025 Funding Request

Table 2 summarizes congressional action on the FY2025 funding request for line items

referencing the V-22 program.

Table 2. Congressional Action on FY2025 Funding Request for Selected V-22

Line Items

(in millions of dollars of budget authority)

Authorization

Appropriation

Line

Type

Request

HASC

SASC

Enacted

HAC

SAC

V-22 (Tilt/Rotor

ACFT) Osprey

[Navy]

Proc.

$235.1

360.1

325.1

V-22 (Medium-Lift)

[Navy]

Proc.

$60.2

V-22A [Navy]

RDT&E

$109.4

CV-22 Mods [Air

Force]

Proc.

CV-22 Modification

[SOCOM]

Proc.

Enacted

295.1

$295.1

$265.1

$60.2

$80.2

$30.2

$109.4

$144.8

$103.9

$108.2

$42.8

$49.4

$40.8

103 For more information, see CRS In Focus IF12771, Future Long-Range Assault Aircraft (FLRAA), by Jennifer

DiMascio.

104 Based on CRS correspondence with Marine Corps officials, February 13, 2025.

105 Based on CRS communications with Bell program officials, October 24, 2024.

106 Based on CRS communications with Bell program officials, October 24, 2024.

107 Steve Trimble, “A Decade in the Making, U.S. Army Nears Final FLRAA Decision,” Aviation Week Intelligence

Network, October 6, 2022.

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

Authorization

Appropriation

CV-22 PostProduction Support

[Air Force]

Proc.

$12.0

CV-22 [Air Force]

RDT&E

$26.2

$535.1

$660.1

$625.1

$595.1

$650.5

$521.0

$525.3

Total

Source: Table prepared by CRS based on U.S. Congress, House Committee on Armed Services, Servicemember

Quality of Life Improvement and National Defense Authorization Act for Fiscal Year 2025, legislative text and joint

explanatory statement to accompany H.R. 5009/P.L. 118-159, 119th Cong., 1st sess., H.Prt. 119-2, January 2025;

H.R. 8774 and H.Rept. 118-557; S. 4921 and S.Rept. 118-204; and DOD’s 1414 Base for Reprogramming Actions,

https://comptroller.defense.gov/Portals/45/Documents/execution/

FY_2025_DD_1414_Base_for_Reprogramming_Actions.pdf.

Notes: HAC is House Appropriations Committee; SAC is Senate Appropriations Committee. Proc. is

procurement. RDT&E is research, development, test, and evaluation. The Full-Year Continuing Appropriations

and Extensions Act, 2025 (H.R. 1968; P.L. 119-4), did not include a list of line-item level dollar amounts for DOD

programs. Section 1422 of the full-year CR required DOD, “after consultation with” defense appropriations

subcommittees, to submit a detailed “spending, expenditure, or operating plan” for FY2025 within 45 days of

enactment (i.e., not later than April 29, 2025). DOD’s DD 1414 Base for Reprogramming Actions details the

DOD’s FY2025 operating plan. See CRS Insight IN12425, FY2025 Defense Appropriations: Summary of Funding, by

Cameron M. Keys. Table does not include additional V-22 funding for spare and repair parts, support equipment,

or certain systems. Table also does not include mandatory funding provided by P.L. 119-21. Figures rounded to

the nearest tenth. Totals may not sum due to rounding.

FY2025 National Defense Authorization Act (H.R. 8070; S. 4638; H.R. 5009; P.L.

118-159)

The House Armed Services Committee, in a report (H.Rept. 118-529) accompanying its version

of the FY2025 NDAA (H.R. 8070), recommended $125.0 million more than requested for line

items referencing the V-22 program (see HASC column of Table 2). The committee report, in

part,

•

directs the Secretary of the Navy to provide a report on how the Navy will

support carrier strike groups when the C-2 Greyhound is retired and restrictions

on CMV-22 flights, including a description of carrier onboard deliveries during

combat operations and a plan for supporting the CMV-22 itself;

directs the Chief of Staff of the Air Force and the Commandant of the Marine

Corps to brief the House Armed Services Committee on expected upgrades to the

V-22;

directs the Secretary of the Navy to brief the House Armed Services Committee

on plans for nacelle improvement, including statistics on mission readiness,

comparing aircraft that have received improved nacelles to those that have not

received improvements;

directs the Chief of Naval Operations, in coordination with the Chief of Staff of

the Air Force and the Commandant of the Marine Corps, to brief the House

Armed Services Committee on planned investments for each variant of the V-22;

and

directs the Secretary of the Air Force to provide a briefing to the House Armed

Services Committee on the proposed force structure for the CV-22 fleet.108

108 H.Rept. 118-529, pp. 20, 21, 22, 32.

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V-22 Osprey: Background and Issues for Congress

The Senate Armed Services Committee, in a report (S.Rept. 118-188) accompanying its version

of the FY2025 NDAA (S. 4638), recommended $90 million more than requested for line items

referencing the V-22 program (see SASC column of Table 2).

The enacted Servicemember Quality of Life Improvement and National Defense Authorization

Act for Fiscal Year 2025 (H.R. 5009; P.L. 118-159) authorized $60 million more than requested

for line items referencing the V-22 program (see enacted authorization column of Table 2),

including $60 million more than requested in the Navy procurement line V-22 (Tilt/Rotor ACFT)

Osprey for “safety enhancements.”109

FY2025 DOD Appropriations Act (H.R. 8774; S. 4921; P.L. 119-4, Division A,

Title IV)

The House Appropriations Committee, in a report (H.Rept. 118-557) accompanying its version of

the Department of Defense Appropriations Act, 2025 (H.R. 8774), recommended $115.4 million

more than requested for line items referencing the V-22 program (see HAC column of Table 2).

The Senate Appropriations Committee, in a report (S.Rept. 118-204) accompanying its version of

the FY2025 DOD Appropriations Act (S. 4921), recommended $90 million more than requested

for line items referencing the V-22 program (see SAC column of Table 2). The committee report,

in part,

•

encourages the Army Program Executive Officer, Aviation to collaborate with the

Navy’s Program Executive Officer, Air Anti-Submarine Warfare, Assault and

Special Mission on lessons learned for the development and operation of tiltrotor

aircraft to ensure insights gained across the V-22 program lifecycle can be

applied early to FLRAA detailed design activities as appropriate, and

directs the Secretary of the Navy to provide quarterly updates to the

congressional defense committees on the status of the NAVAIR-led

comprehensive review of the V-22 program, as well as a final report on the

findings and implementation plan of all recommendations, not later than 90-days

following the completion of NAVAIR’s comprehensive review.110

The enacted version of the FY2025 DOD Appropriations Act (P.L. 119-4, Division A, Title IV)

appropriated $9.8 million less than requested for line items referencing the V-22 program (see the

enacted appropriations column of Table 2).111

FY2026

Summary of Congressional Action on FY2026 Funding Request

Table 3 summarizes congressional action on the FY2026 funding request for line items

referencing the V-22 program.

109 H.Prt. 119-2, p. 1223.

110 S.Rept. 118-204, p. 92.

111 DOD’s 1414 Base for Reprogramming Actions, https://comptroller.defense.gov/Portals/45/Documents/execution/

FY_2025_DD_1414_Base_for_Reprogramming_Actions.pdf; and FY2026 DOD budget justification documentation.

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V-22 Osprey: Background and Issues for Congress

Table 3. Congressional Action on FY2026 Funding Request for Selected V-22

Line Items

(in millions of dollars of budget authority)

Line

V-22 (Tilt/Rotor

ACFT) Osprey

[Navy]

V-22 (Medium-Lift)

[Navy]

V-22A [Navy]

CV-22 Mods [Air

Force]

CV-22 Modification

[SOCOM]

CV-22 PostProduction Support

[Air Force]

CV-22 [Air Force]

Authorization

HASC

SASC

Enacted

$319.1

Appropriation

HAC

SAC

Enacted

$247.8

$309.1

Type

Proc.

Request

$319.1

Proc.

$47.2

$50.9

$47.2

RDT&

Proc.

$125.0

$144.8

$125.0

$78.7

$100.4

$78.7

Proc.

$19.7

Proc.

RDT&

Total

$5.1

$0.7

$30.9

$0.7

$590.4

$594.4

$580.4

Source: Table prepared by CRS based on H.R. 3838 and H.Rept. 119-231; S. 2296 and S.Rept. 119-39; H.R.

4016 and H.Rept. 119-162; S. 2572 and S.Rept. 119-52.

Notes: HAC is House Appropriations Committee; SAC is Senate Appropriations Committee. Proc. is

procurement. RDT&E is research, development, test, and evaluation. Table does not include funding for V-22

spare and repair parts, support equipment, or certain systems. Table also does not include mandatory funding

provided by P.L. 119-21. Figures rounded to the nearest tenth. Totals may not sum due to rounding.

Proposals for FY2026 National Defense Authorization Act (H.R. 3838; S. 2296)

The House Armed Services Committee, in a report (H.Rept. 119-231) accompanying its version

of the Streamlining Procurement for Effective Execution and Delivery and National Defense

Authorization Act for Fiscal Year 2026 (H.R. 3838), recommended the requested amounts for line

items referencing the V-22 program (see HASC column of Table 3). The committee, in the report,

•

encourages the Department of Defense to prioritize funding for essential

upgrades, such as nacelle improvement, digital interoperability enhancements,

and sustainment that increase aircraft availability, and

directs the Secretary of the Navy, in coordination with the Secretary of the Air

Force, to submit a briefing to the House Committee on Armed Services not later

than December 1, 2025, on the near- and long-term modernization strategy for

the V-22 fleet.112

The Senate Armed Services Committee, in a report (S.Rept. 119-39) accompanying its version of

an FY2026 NDAA (S. 2296), recommended the requested amount for line items referencing the

V-22 program (see SASC column of Table 3). The committee, in the report,

112 H.Rept. 119-231, pp. 24.

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V-22 Osprey: Background and Issues for Congress

•

directs the Comptroller General to conduct a review of the V-22 program’s safety,

cost, reliability, and performance to include an assessment of DOD efforts to

incorporate lessons learned from the V-22 program for the FLRAA program;113

encourages the Secretary of the Navy to integrate nacelle improvements into the

CMV-22B aircraft fleet;114 and

directs the Comptroller General to assess the Department of the Army’s FLRAA

program and consider the extent to which the Army and contractors incorporated

V-22 lessons into the design, risk reduction, and plans for operation and

maintenance of FLRAA.115

Proposals for FY2026 DOD Appropriations Act (H.R. 4016; S. 2572)

The House Appropriations Committee, in a report (H.Rept. 119-162) accompanying its version of

a DOD Appropriations Act, 2026 (H.R. 4016), recommended $4.0 million more than requested

for line items referencing the V-22 program (see HAC column of Table 3). The committee, in the

report,

•

directs the Commander of Special Operations Command to submit to the House

and Senate Committees on Appropriations, Subcommittees on Defense, a report,

with a follow-on briefing, that includes the results of accident investigations

pertaining to any crash of the CV-22 Osprey since the introduction of the aircraft

or other mishap findings involving the failure of the single high-speed planetary

pinion gear.116

The Senate Appropriations Committee, in a report (S.Rept. 119-52) accompanying its version of

an FY2026 DOD Appropriations Act (S. 2572), recommended $10 million less than requested for

line items referencing the V-22 program (see SAC column of Table 3).

Potential Considerations for Congress

Congress may or may not approve funding for the modernization, future purchase, and operation

of the V-22. Congress also may provide oversight about the platform’s safety. Congress has asked

for information about aircraft carrier logistics support, nacelle improvement, investment in

upgrades, CV-22 force structure, and the program as a whole. Some additional matters for

Congress to consider include the following:

Size of V-22 Fleets

DOD plans call for V-22 production to end in 2028; procurement funding requested in FY2026

would not fund the acquisition of new aircraft. Rather it is for components and production line

shutdown costs, among other activities. One potential issue for Congress is whether DOD has

enough, too many, or too few V-22s to meet operational requirements.

Some analysts argue that the Navy should buy more CMV-22s to respond to the Navy’s logistics

needs, which are growing as the Navy moves toward Distributed Maritime Operations (DMO) for

113 S.Rept. 119-39, pp. 17-18.

114

S.Rept. 119-39, pp. 16-17.

115 S.Rept. 119-39, p. 51.

116 H.Rept. 119-162, p. 54.

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V-22 Osprey: Background and Issues for Congress

operations in the Asia-Pacific.117 These analysts contend that the CMV-22’s vertical take-off and

landing capability—even at night—enables the aircraft to provide logistics support without a need

for the aviation infrastructure, such as runways, required by the C-2 Greyhound cargo aircraft.118

Congress may consider seeking additional information about the CMV-22’s role in DMO and

whether or not to provide funding to maintain production of the CMV-22 beyond plans to close

the production line in 2028. Congress may also consider whether to pursue alternatives to the

CMV-22.

Separately, some Members have asked for a report about the Air Force CV-22 force structure. A

report accompanying the HASC-reported version of the FY2025 NDAA (H.R. 8070; H.Rept.

119-529) questioned the adequacy of CV-22 fleet size, stating that the Air Force has put CV-22s

in storage until 2026. The Air Force has reportedly transferred certain CV-22s to storage in part to

better maintain and operate a more limited number of aircraft.119 A potential question for

Congress is whether the U.S. military has the capacity to increase the number of V-22s in service,

given declining readiness rates for the aircraft. A Congressional Budget Office (CBO) report

released in November 2024 analyzed the availability of DOD’s rotary wing aircraft.120 CBO

found that the Air Force CV-22 availability has declined from a 61% availability rate in 2017 to a

33% availability rate in 2023. The study was conducted using data before the November 29,

2023, fatal V-22 mishap.121

Congress may evaluate requested information from the Air Force to provide oversight regarding

decisions about the future size of AFSOC’s CV-22 fleet and funding, as well as future plans for

nacelle improvement.

Aircraft Carrier Logistics

As noted above, the Navy is phasing in the CMV-22 to replace the C-2 Greyhound for carrier

onboard delivery missions until 2026. The CMV-22 remains under a 30-minute flight restriction.

The Navy has indicated that it anticipates the CMV-22B will “return to its full operating envelope

in support of this transition with no interruption to the mission.”122

Citing the V-22 safety record and flight restrictions, some Members have asked what other

platforms the Navy might use as an alternative to the CMV-22 for carrier onboard delivery. Navy

officials say that a heavy-lift helicopter, such as the CH-53K, is capable of undertaking the C-2

mission.123 Congress may consider whether or not to direct the Navy to further extend the use of

the C-2, whether or not to direct the Navy study alternatives to the CMV-22, or whether or not to

fund the CMV-22.

117 Sandy Clark, “Time to Double Down on Naval Combat Logistics with the Osprey,” Real Clear Defense, June 14,

2024, https://www.realcleardefense.com/articles/2024/06/14/

time_to_double_down_on_naval_combat_logistics_with_the_osprey_1038039.html. For information about DMO, see

CRS In Focus IF12599, Defense Primer: Navy Distributed Maritime Operations (DMO) Concept, by Ronald O'Rourke.

118 Tim Hanifen, “The CMV-22 Osprey: A Game-Changer for Today’s COD and Tomorrow’s Contested Combat

Logistics Support,” Center for Maritime Strategy, August 13, 2024, https://centerformaritimestrategy.org/publications/

the-cmv-22-osprey-a-game-changer-for-todays-cod-and-tomorrows-contested-combat-logistics-support/.

119 Greg Hadley, “AFSOC Put 15 CV-22 Ospreys in Storage to Increase Mission Readiness for Rest of Fleet,” Air and

Space Forces Magazine, May 24, 2024, https://www.airandspaceforces.com/afsoc-cv-22-ospreys-flyable-storage/.

120 Congressional Budget Office (CBO), “Availability and Use of Rotary-Wing Aircraft in the Department of Defense,”

November 2024, https://www.cbo.gov/system/files/2024-11/60663-dod-rotary-wing.pdf.

121

CBO, “Availability and Use of Rotary-Wing Aircraft in the Department of Defense.”

122 Based on CRS correspondence with NAVAIR, PMA-275, October 3, 2024.

123 Based on CRS communications with NAVAIR officials, September 19, 2024.

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V-22 Osprey: Background and Issues for Congress

Funding for Future Upgrades

One potential issue for Congress is whether or not to support the Marines’ stated intention to

continue operating the MV-22 until 2055. DOD may request future authorization and

appropriation of funding for upgrades, such as the VeCToR and ReVAMP initiatives described

above.

Marine Corps officials say that the V-22’s speed, range, and ability to refuel made the Osprey

essential to operations in Afghanistan and will make it an asset in the Indo-Pacific region. They

argue that its safety record is comparable to other aircraft in its fleet. A Marine Corps official told

Members that initial flight restrictions on the MV-22 hampered about 75% of the Marines’ assault

support, because the MV-22 is critical to the contested logistics mission.124

Congress in the FY2025 NDAA (H.R. 5009; P.L. 118-159) authorized an additional $60 million

for V-22 safety enhancements. Some Members have asked for additional information about DOD

plans. Congress may use the results to consider whether or not to authorize or appropriate funding

for future upgrades.

Safety Investigation Reports

The House Committee on Government Oversight has expressed frustration about a lack of access

to safety investigation reports. A July 16, 2024, letter to then-Defense Secretary Lloyd Austin

requesting those reports and information about all Osprey class A mishaps since 1991 states: “If

DoD continues to fail to produce the requested documents by July 30, 2024, the Committee will

consider additional measures, including use of the compulsory process, to gain compliance and

obtain this critical material.”125

DOD Instruction 6055.07 states that “components protect privileged safety information to ensure

commanders quickly obtain accurate mishap information.” The instruction also lays out

guidelines for privileged information within safety investigations, including the promise of

confidentiality to sources who provide information.126

As previously discussed, DOD has an agreement with the chairs and ranking members of the

House and Senate Committees on Armed Services to provide them with briefings, by request, on

the results of safety investigation boards. Congress may or may not consider changing this

agreement to include more Members and/or professional staff of the committees. Broader

dissemination of the results of a safety investigation board could increase transparency and help

Congress provide oversight. On the other hand, a wider release of the findings could have

unintended consequences, such as compromising the confidentiality of sources assisting with an

investigation.

Maintenance Training

Some analysts have said that the development, training, and education of Marine aviation

technicians and maintainers have not kept pace with the rate of innovation in the Marine aircraft

124 CQ Transcripts, “House Armed Services Subcommittee on Readiness Holds Hearing on the Fiscal Year 2025

Military Readiness Budget Request,” April 30, 2024.

125 Letter from Comer and Grothman to Lloyd Austin, July 16, 2024.

126 DOD Instruction 6055.07, “Mishap Notification, Investigation, Reporting, and Record Keeping.”

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V-22 Osprey: Background and Issues for Congress

fleet, including for the MV-22.127 They argue that to be more successful, maintenance technicians

need the kind of squadron-specific training that pilots and aircrews receive.128 Congress could

consider the costs and benefits of offering squadron-specific training for aircrew maintainers.

Congress could also consider whether or not to provide additional funding for squadron-level

maintenance training.

127 Chief Warrant Officer 3 Brian P. Brewer, U.S. Marine Corps, “Aviation Maintenance: A Critical Vulnerability in

the Marine Corps,” U.S. Naval Institute, November 2024, https://www.usni.org/magazines/proceedings/2024/

november/aviation-maintenance-critical-vulnerability-marine-corps.

128 Brewer, “Aviation Maintenance: A Critical Vulnerability in the Marine Corps.”

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V-22 Osprey: Background and Issues for Congress

Appendix. Safety Statistics

The table below compares the Class A Mishap rates per 100,000 flight hours of the V-22 against

other selected Marine Corps and Air Force rotary-wing aircraft, including the Marines’ AH-1Z

attack helicopter, the CH-53E heavy-lift transport helicopter, and the UH-1Y medium-sized utility

helicopter. Other Air Force rotorcraft include the HH-60 medium-lift utility helicopter and the H1 helicopter. It does not include the CMV-22, which has not experienced any Class A Flight

Mishaps.

Table A-1. Selected Marine Corps and Air Force Class A

Flight Mishaps and Mishap Rates, FY2015-FY2024

(Number and Rate, by Service and Type of Aircraft)

Aircraft Type

Number of Mishaps

Rate

2.67

AH-IZ

0.81

CH-53E

5.49

MV-22B

2.56

UH-1Y

1.54

293

1.65

HH-60

1.29

H-1

0.66

CV-22

11.55

All U.S. Marine Corps

aircraft

All U.S. Air Force aircraft

Source: Marine Corps data provided by Marine Corps Legislative Liaison, December 12, 2024; Air Force data

provided by Air Force Legislative Liaison, January 7, 2025.

Notes: Rate of Class A Flight Mishaps is calculated based on 100,000 flight hours.

Table A-2. Number of Fatalities Due to V-22 Mishaps

(across all V-22 variants)

1991-2007

2007-2025

Source: Marine Corps Legislative Liaison, Air Force Legislative Liaison, Aviation Safety Network Database,

https://asn.flightsafety.org/asndb/type/V22.

Note: The first V-22 variant to achieve initial operational capability was the MV-22 in 2007.

Author Information

Jennifer DiMascio

Analyst in U.S. Defense Policy

Congressional Research Service

V-22 Osprey: Background and Issues for Congress

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R48703 · VERSION 1 · NEW

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