Airworthiness Directives; Jetstream Model 4101 Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-25-AD; Amendment 39-9100; AD 94-26-04]

Airworthiness Directives; Jetstream Model 4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive

(AD), applicable to certain Jetstream Model 4101 airplanes, that

currently requires inspections to detect damage of the ball bearings in

the aileron quadrants, replacement of damaged ball bearings with new

ball bearings, and adjustment to the secondary stops. This amendment

requires installation of new swivel bearings in the aileron quadrants,

which, when accomplished, will terminate the inspection requirement.

This amendment is prompted by the development of a modification that

eliminates the need to inspect repetitively. The actions specified by

this AD are intended to prevent failure of the bearings in the aileron

quadrants, which could result in reduced controllability of the

airplane.

DATES: Effective January 26, 1995.

The incorporation by reference of Jetstream Alert Service Bulletin

J41-A-27-026, Revision 2, dated January 17, 1994, and Jetstream Service

Bulletin J41-27-027, dated January 17, 1994, is approved by the

Director of the Federal Register as of January 26, 1995.

The incorporation by reference of Jetstream Alert Service Bulletin

J41-A-27-026, Revision 1, dated December 7, 1993, was approved

previously by the Director of the Federal Register as of March 28, 1994

(59 FR 11531, March 11, 1994).

ADDRESSES: The service information referenced in this AD may be

obtained from Jetstream Aircraft, Incorporated, P.O. Box 16029, Dulles

International Airport, Washington, DC 20041-6029. This information may

be examined at the Federal Aviation Administration (FAA), Transport

Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton,

Washington; or at the Office of the Federal Register, 800 North Capitol

Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: William Schroeder, Aerospace Engineer,

Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)

227-2148; fax (206) 227-1320.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal

Aviation Regulations (14 CFR part 39) by superseding AD 93-25-10,

Amendment 39-8849 (59 FR 11531, March 11, 1994), which is applicable to

certain Jetstream Model 4101 airplanes, was published in the Federal

Register on May 4, 1994 (59 FR 23031). The action proposed to require

installation of new swivel bearings in the left and right aileron

quadrants (Modification JM41307A) as terminating action for the

currently required inspections.

Interested persons have been afforded an opportunity to participate

in the making of this amendment. No comments were submitted in response

to the proposal or the FAA's determination of the cost to the public.

The FAA has recently reviewed the figures it has used over the past

several years in calculating the economic impact of AD activity. In

order to account for various inflationary costs in the airline

industry, the FAA has determined that it is necessary to increase the

labor rate used in these calculations from $55 per work hour to $60 per

work hour. The economic impact information, below has been revised to

reflect this increase in the specified hourly labor rate.

As a result of recent communications with the Air Transport

Association (ATA) of America, the FAA has learned that, in general,

some operators may misunderstand the legal effect of AD's on airplanes

that are identified in the applicability provision of the AD, but that

have been altered or repaired in the area addressed by the AD. Under

these circumstances, at least one operator appears to have incorrectly

assumed that its airplane was not subject to an AD. On the contrary,

all airplanes identified in the applicability provision of an AD are

legally subject to the AD. If an airplane has been altered or repaired

in the affected area in such a way as to affect compliance with the AD,

the owner or operator is required to obtain FAA approval for an

alternative method of compliance with the AD, in accordance with the

paragraph of each AD that provides for such approvals. A note has been

added to this final rule to clarify this requirement. The FAA has

determined that this addition will neither increase the economic burden

on any operator nor increase the scope of the AD.

The FAA estimates that 8 airplanes of U.S. registry will be

affected by this AD.

The inspections that were previously required by AD 93-25-10, and

retained in this amendment, take approximately 1 work hour per airplane

to accomplish, at an average labor rate of $60 per work hour. Based on

these figures, the total cost impact of these inspection requirements

on U.S. operators is estimated to be $480, or $60 per airplane, per

inspection cycle.

The adjustment to the secondary stops that were previously required

by AD 93-25-10, and retained in this amendment, take approximately 1

work hour per airplane to accomplish, at an average labor rate of $60

per work hour. Based on these figures, the total cost impact of this

adjustment requirement on U.S. operators is estimated to be $480, or

$60 per airplane. The FAA estimates that all affected U.S. operators

have already accomplished this action; therefore, the future cost

impact of this requirement is minimal.

The installation of new swivel bearings (Modification JM41307A)

that will be required by this amendment will take approximately 10 work

hours per airplane to accomplish, at an average labor rate of $60 per

work hour. Required parts will be provided by the manufacturer at no

cost to the operator. Based on these figures, the total cost impact of

the modification requirement of this AD on U.S. operators is estimated

to be $4,800, or $600 per airplane.

The total cost impact figure discussed above is based on

assumptions that no operator has yet accomplished any of the

requirements of this AD action, and that no operator would accomplish

those actions in the future if this AD were not adopted.

The regulations adopted herein will not have substantial direct

effects on the States, on the relationship between the national

government and the States, or on the distribution of power and

responsibilities among the various levels of government. Therefore, in

accordance with Executive Order 12612, it is determined that this final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (1) is

not a ``significant regulatory action'' under Executive Order 12866;

(2) is not a ``significant rule'' under DOT Regulatory Policies and

Procedures (44 FR 11034, February 26, 1979); and (3) will not have a

significant economic impact, positive or negative, on a substantial

number of small entities under the criteria of the Regulatory

Flexibility Act. A final evaluation has been prepared for this action

and it is contained in the Rules Docket. A copy of it may be obtained

from the Rules Docket at the location provided under the caption

ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by

reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the

Administrator, the Federal Aviation Administration amends part 39 of

the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.

106(g); and 14 CFR 11.89.

39.13 [Amended]

2. Section 39.13 is amended by removing amendment 39-8849 (59 FR

11531, March 11, 1994), and by adding a new airworthiness directive

(AD), amendment 39-9100 to read as follows:

94-26-04 Jetstream Aircraft Limited: Amendment 39-9100. Docket 94-

NM-25-AD. Supersedes AD 93-25-10, Amendment 39-8849.

Applicability: Model 4101 airplanes having constructors numbers

41004 and subsequent; on which Modification JM41307A or JM41307B has

not been installed previously; certificated in any category.

Note 1: This AD applies to each airplane identified in the

preceding applicability provision, regardless of whether it has been

modified, altered, or repaired in the area subject to the

requirements of this AD. For airplanes that have been modified,

altered, or repaired so that the performance of the requirements of

this AD is affected, the owner/operator must use the authority

provided in paragraph (e) to request approval from the FAA. This

approval may address either no action, if the current configuration

eliminates the unsafe condition; or different actions necessary to

address the unsafe condition described in this AD. Such a request

should include an assessment of the effect of the changed

configuration on the unsafe condition addressed by this AD. In no

case does the presence of any modification, alteration, or repair

remove any airplane from the applicability of this AD.

Compliance: Required as indicated, unless accomplished

previously.

To prevent failure of the bearings in the aileron quadrants,

which could result in reduced controllability of the airplane,

accomplish the following:

(a) Within 7 days after March 28, 1994 (the effective date of AD

93-25-10, Amendment 39-8849), perform a detailed visual inspection

to detect damage of the bearings in the aileron quadrant in the

pilot's and co-pilot's aileron control, in accordance with Jetstream

Aircraft Limited Alert Service Bulletin J41-A-27-026, Revision 1,

dated December 7, 1993; or Revision 2, dated January 17, 1994.

(1) If no damaged bearing is found, repeat the inspection,

thereafter, at intervals not to exceed 7 days.

(2) If any damaged bearing is found, prior to further flight,

replace the damaged bearing with a new bearing in accordance with

the service bulletin, and repeat the inspection, thereafter, at

intervals not to exceed 7 days.

Note 2: Paragraph (a) of this AD restates the requirement for an

initial and repetitive inspections contained in paragraph (a) of AD

93-25-10. Therefore, for operators that have previously accomplished

at least the initial inspection in accordance with AD 93-25-10,

paragraph (a) of this AD requires that the next scheduled inspection

be performed within 7 days after the last inspection performed in

accordance with paragraph (a) of AD 93-25-10.

(b) Within 7 days after March 28, 1994 (the effective date of AD

93-25-10, Amendment 39-8849), adjust the aileron secondary stop in

the pilot's and co-pilot's aileron control system in accordance with

Jetstream Aircraft Limited Alert Service Bulletin J41-A-27-026,

Revision 1, dated December 7, 1993; or Revision 2, dated January 17,

1994.

Note 3: Paragraph (b) of this AD restates the requirement to

adjust the aileron secondary stop contained in paragraph (b) of AD

93-25-10. As allowed by the phrase ``unless accomplished

previously,'' if that requirement of AD 93-25-10 has been

accomplished previously, this AD does not require that it be

repeated.

(c) Within 7 days after March 28, 1994 (the effective date of AD

93-25-10, Amendment 39-8849), revise the Abnormal Procedures Section

of the FAA-approved Airplane Flight Manual (AFM) to include the

following. This may be accomplished by inserting a copy of this AD

in the AFM:

``Where abnormal aileron control backlash is experienced by one

pilot, the other pilot should assume control of the aircraft without

using the disconnect facility. The disconnect facility should only

be used in accordance with published procedures in cases of control

restrictions or jamming.''

Note 4: Paragraph (c) of this AD restates the requirement for an

AFM revision contained in paragraph (c) of AD 93-25-10. As allowed

by the phrase ``unless accomplished previously,'' if that

requirement of AD 93-25-10 has been accomplished previously, this AD

does not require that it be repeated.

-(d) Within 180 hours time-in-service after the effective date

of this AD, install new swivel bearings in the left and right

aileron quadrants (Modification JM41307A) in accordance with

Jetstream Service Bulletin J41-27-027, dated January 17, 1994.

Accomplishment of this modification constitutes terminating action

for the requirements of this AD. The AFM revision required by

paragraph (c) of this AD may be removed following accomplishment of

this modification.

(e) An alternative method of compliance or adjustment of the

compliance time that provides an acceptable level of safety may be

used if approved by the Manager, Standardization Branch, ANM-113,

FAA, Transport Airplane Directorate. Operators shall submit their

requests through an appropriate FAA Principal Maintenance Inspector,

who may add comments and then send it to the Manager,

Standardization Branch, ANM-113.-

Note 5: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the Standardization Branch, ANM-113.

-(f) Special flight permits may be issued in accordance with

Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR

21.197 and 21.199) to operate the airplane to a location where the

requirements of this AD can be accomplished. -

(g) The actions shall be done in accordance with Jetstream

Service Bulletin J41-27-027, dated January 17, 1994; and Jetstream

Alert Service Bulletin J41-A-27-026, Revision 1, dated December 7,

1993, or Jetstream Alert Service Bulletin J41-A-27-026, Revision 2,

dated January 17, 1994, as applicable. Revision 2 of Jetstream Alert

Service Bulletin J41-A-27-026 contains the following list of

effective pages:

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Revision level

Service bulletin referenced and date Page No. shown on page Date shown on page

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J41-A-27-026......................................... 1-3 2 January 17, 1994.

Revision 2

January 17, 1994..................................... 4-9 1 December 7, 1993.

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The incorporation by reference of Jetstream Alert Service

Bulletin J41-A-27-026, Revision 1, dated December 7, 1993, was

approved previously by the Director of the Federal Register in

accordance with 5 U.S.C. 552(a) and 1 CFR Part 51 as of March 28,

1994 (59 FR 11531, March 11, 1994). The incorporation by reference

of the remainder of the service bulletins listed above is approved

by the Director of the Federal Register in accordance with 5 U.S.C.

552(a) and 1 CFR Part 51. Copies may be obtained from Jetstream

Aircraft, Incorporated, P.O. Box 16029, Dulles International

Airport, Washington, DC 20041-6029. Copies may be inspected at the

FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,

Washington; or at the Office of the Federal Register, 800 North

Capitol Street, NW., suite 700, Washington, DC. -

(h) This amendment becomes effective on January 26, 1995.

Issued in Renton, Washington, on December 14, 1994.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-31178 Filed 12-23-94; 8:45 am]

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