[Federal Register Volume 61, Number 203 (Friday, October 18, 1996)]
[Proposed Rules]
[Pages 54366-54368]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-26706]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-NM-26-AD]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Model BAe 146 and 
Avro 146-RJ Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of two existing 
airworthiness directives (AD), applicable to British Aerospace Model 
BAe 146 and Avro 146-RJ series airplanes, that currently require 
inspections to detect cracking of the upper main fitting of the nose 
landing gear (NLG), and replacement or repair of cracked parts, if 
necessary. Those actions were prompted by reports of cracking in the 
main fittings of the NLG. This action would require that, for certain 
airplanes, the inspections be accomplished at reduced intervals. This 
proposal is prompted by the results of new analyses of the cracking 
that were conducted by the manufacturer of the NLG. The actions 
specified by the proposed AD are intended to prevent failure of the 
main fitting, which could lead to collapse of the NLG during landing.

DATES: Comments must be received by November 25, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-26-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal 
holidays.
    The service information referenced in the proposed rule may be 
obtained from British Aerospace Holding, Inc., Avro International 
Aerospace Division, P.O. Box 16039, Dulles International Airport, 
Washington DC 20041-6039. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2797; fax (206) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 96-NM-26-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules 
Docket No. 96-NM-26-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On August 23, 1993, the FAA issued AD 93-17-04, amendment 39-8674 
(58 FR 47036, September 7, 1993), applicable to British Aerospace Model 
BAe 146 series airplanes, to require repetitive inspections to detect 
cracking of the upper main fitting of the nose landing gear (NLG), and 
replacement or repair of cracked parts, if necessary. That action was 
prompted by reports of cracking of the upper main fitting of the NLG. 
The requirements of that AD are intended to prevent failure of the main 
fitting, which could lead to collapse of the NLG during landing.
    On February 15, 1995, the FAA issued AD 95-04-06, amendment 39-9158 
(60 FR 12413, March 7, 1995), applicable to British Aerospace Model 
Avro 146-RJ series airplanes. That AD is similar to AD 93-17-04 in that 
it requires repetitive inspections to detect cracking of the upper main 
fitting of the NLG, and replacement or repair of cracked parts, if 
necessary. Likewise, that action was prompted by reports of cracking of 
the upper main fitting of the NLG. The requirements of that AD are 
intended to prevent failure of the main fitting, which could lead to 
collapse of the NLG during landing.

Action Since Issuance of Previous AD's

    Since the issuance of those AD's, a fatigue analysis and a review 
of the service reports were conducted by the manufacturer of the NLG. 
The results of the analysis and review indicate that crack growth can 
occur at a faster rate than what was considered previously. The 
repetitive inspection interval should be reduced for NLG part number

[[Page 54367]]

200876001 or 200876003 from 4,000 landings to 2,000 landings. The 
results of the review and analysis also indicated that the current 
repetitive inspection interval of 8,000 landings is adequate for NLG 
part numbers 200876002, 200876004, and 201138002.

Explanation of Relevant Service Information

    Subsequent to the fatigue analysis and review of the service 
reports, British Aerospace issued Service Bulletin S.B. 32-131, 
Revision 3, dated October 18, 1995, which describes procedures for 
either an eddy current or ultra sensitive penetrant inspection of the 
NLG to detect cracking, and replacement or repair of cracked parts, if 
necessary. (The service bulletin also references Messier-Dowty Service 
Bulletin, Revision 2, dated August 2, 1995, as an additional source of 
service information.) The CAA classified the British Aerospace service 
bulletin as mandatory in order to assure the continued airworthiness of 
these airplanes in the United Kingdom.

FAA's Conclusions

    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the CAA, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would supersede AD 93-17-04 and 
AD 95-04-06 to continue to require either eddy current or ultra 
sensitive penetrant inspections to detect cracking of the upper main 
fitting of the NLG, and replacement or repair of cracked parts, if 
necessary. Although the inspections required by this proposal are the 
same as the inspections required by AD 93-17-04 and AD 95-04-06, this 
proposal would combine the requirements of the previous AD's, but 
require that the repetitive inspection interval for certain airplanes 
(equipped with certain NLG part numbers) would occur more frequently. 
The actions would be required to be accomplished in accordance with the 
British Aerospace service bulletin described previously.

Cost Impact

    There are approximately 52 Model BAe 146 and Model Avro 146-RJ 
series airplanes of U.S. registry that would be affected by this 
proposed AD.
    The inspections that are currently required by AD 93-17-04 and AD 
95-04-06, and retained in this proposal, take approximately 3 work 
hours per airplane to accomplish, at an average labor rate of $60 per 
work hour. Based on these figures, the cost impact on U.S. operators of 
the actions currently required is estimated to be $9,360, or $180 per 
airplane, per inspection cycle.
    Although this proposal adds no new actions, the associated costs 
for some operators would increase somewhat since certain inspections 
would be required to be performed more frequently.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-8674 (58 FR 
47036, September 7, 1993), and amendment 39-9158 (60 FR 12413, March 7, 
1995), and by adding a new airworthiness directive (AD), to read as 
follows:

British Aerospace Regional Aircraft Limited, AVRO International: 
Docket 96-NM-26-AD. Supersedes AD 93-17-04, Amendment 39-8674; and 
AD 95-04-06, Amendment 39-9158.

    Applicability: Model BAe 146 and Avro 146-RJ series airplanes, 
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 request approval for an 
alternative method of compliance in accordance with paragraph (f) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the failure of the main fitting, which could lead to 
collapse of the nose landing gear (NLG) during landing, accomplish 
the following:

Restatement of Continuing Requirements

    (a) For all Model BAe 146 series airplanes on which NLG part 
number 200876002, 200876004, or 201138002 has been installed:
    (1) Prior to the accumulation of 16,000 total landings or within 
30 days after October 7, 1993 (the effective date of AD 93-17-04, 
Amendment 39-8674), whichever occurs later, conduct an eddy current 
or ultra sensitivity penetrant inspection of the NLG, in accordance 
with British Aerospace Service Bulletin S.B. 32-131, dated December 
6, 1991; Revision 1, dated November 12, 1992;

[[Page 54368]]

Revision 2, dated July 10, 1993; or Revision 3, dated October 18, 
1995. Repeat the inspection thereafter at intervals not to exceed 
8,000 landings.
    (2) If cracking is detected during any inspection required by 
this paragraph, prior to further flight, replace the currently 
installed NLG with a new or serviceable unit, or repair the crack, 
in accordance with a method approved by the Manager, Standardization 
Branch, ANM-113, FAA, Transport Airplane Directorate. After 
replacement or repair, repeat the inspection at intervals not to 
exceed 8,000 landings.
    (b) For all Model Avro 146-RJ series airplanes on which NLG part 
number 200876002, 200876004, or 201138002 has been installed:
    (1) Prior to the accumulation of 16,000 total landings or within 
30 days after April 6, 1995 (the effective date of AD 95-04-06, 
Amendment 39-9158), whichever occurs later, conduct an eddy current 
or ultra sensitivity penetrant inspection of the NLG, in accordance 
with British Aerospace Service Bulletin S.B. 32-131, dated December 
6, 1991; Revision 1, dated November 12, 1992; Revision 2, dated July 
10, 1993; or Revision 3, dated October 18, 1995. Repeat the 
inspection thereafter at intervals not to exceed 8,000 landings.
    (2) If cracking is detected during any inspection required by 
this paragraph, prior to further flight, replace the currently 
installed NLG with a new or serviceable unit, or repair the crack, 
in accordance with a method approved by the Manager, Standardization 
Branch, ANM-113, FAA, Transport Airplane Directorate. After 
replacement or repair, repeat the inspection at intervals not to 
exceed 8,000 landings.
    (c) For all Model BAe 146 series airplanes on which NLG part 
number 200876001 or 200876003 has been installed:
    (1) Prior to the accumulation of 4,000 total landings or within 
30 days after October 7, 1993 (the effective date of AD 93-17-04, 
Amendment 39-8674), whichever occurs later, conduct an eddy current 
or ultra high sensitivity penetrant inspection of the NLG, in 
accordance with British Aerospace Service Bulletin S.B. 32-131, 
dated December 6, 1991; Revision 1, dated November 12, 1992; 
Revision 2, dated July 10, 1993; or Revision 3, dated October 18, 
1995. Repeat the inspection thereafter at intervals not to exceed 
4,000 landings until the inspection required by paragraph (e) of 
this AD is accomplished.
    (2) If cracking is detected during any inspection required by 
this paragraph, prior to further flight, replace the currently 
installed NLG with a new or serviceable unit, or repair the crack, 
in accordance with a method approved by the Manager, Standardization 
Branch, ANM-113, FAA, Transport Airplane Directorate. After 
replacement or repair, repeat the inspection at intervals not to 
exceed 4,000 landings until the inspection required by paragraph (e) 
of this AD is accomplished.
    (d) For all Model Avro 146-RJ series airplanes on which NLG part 
number 200876001 or 200876003 has been installed:
    (1) Prior to the accumulation of 4,000 total landings or within 
30 days after April 6, 1995 (the effective date of AD 95-04-06, 
Amendment 39-9158), whichever occurs later, conduct an eddy current 
or ultra high sensitivity penetrant inspection of the NLG, in 
accordance with British Aerospace Service Bulletin S.B. 32-131, 
dated December 6, 1991; Revision 1, dated November 12, 1992; 
Revision 2, dated July 10, 1993; or Revision 3, dated October 18, 
1995. Repeat the inspection thereafter at intervals not to exceed 
4,000 landings until the inspection required by paragraph (e) of 
this AD is accomplished.
    (2) If cracking is detected during any inspection required by 
this paragraph, prior to further flight, replace the currently 
installed NLG with a new or serviceable unit, or repair the crack, 
in accordance with a method approved by the Manager, Standardization 
Branch, ANM-113, FAA, Transport Airplane Directorate. After 
replacement or repair, repeat the inspection at intervals not to 
exceed 4,000 landings until the inspection required by paragraph (e) 
of this AD is accomplished.

New Requirements

    (e) For all Model BAe 146 and Avro 146-RJ series airplanes on 
which NLG part number 200876001 or 200876003 has been installed: 
Within 2,000 landings from the immediately preceding inspection 
conducted in accordance with paragraph (c) or (d) of this AD, or 
within 3 months after the effective date of this AD, whichever 
occurs later, accomplish the following:
    (1) Conduct an eddy current or ultra high sensitivity penetrant 
inspection of the NLG, in accordance with British Aerospace Service 
Bulletin S.B. 32-131, Revision 3, dated October 18, 1995. Repeat the 
inspection thereafter at intervals not to exceed 2,000 landings. 
Accomplishment of this inspection terminates the requirements of 
paragraph (c) and (d) of this AD.

    Note 2: The British Aerospace service bulletin references a 
Messier-Dowty Service Bulletin 145-32-109, Revision 2, dated August 
2, 1995, as an additional source of service information.

    (2) If cracking is detected during any inspection required by 
this paragraph, prior to further flight, replace the currently 
installed NLG with a new or serviceable unit, or repair the crack, 
in accordance with a method approved by the Manager, Standardization 
Branch, ANM-113. After replacement or repair, repeat the inspection 
at intervals not to exceed 2,000 landings.
    (f) 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. 
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 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (g) Special flight permits may be issued in accordance with 
sections 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.

    Issued in Renton, Washington, on October 9, 1996.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-26706 Filed 10-17-96; 8:45 am]
BILLING CODE 4910-13-U