AD 97-06-12

This amendment supersedes 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 amendment requires that, for certain airplanes, the inspections be accomplished at reduced intervals. This amendment is prompted by the results of new analyses of the cracking that were conducted by the manufacturer of the NLG. The actions specified by this AD are intended to prevent failure of the main fitting, which could lead to collapse of the NLG during landing.

Final rule

97-06-12 BRITISH AEROSPACE REGIONAL AIRCRAFT LIMITED, AVRO INTERNATIONAL: Amendment 39-9969. 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 specificproposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent 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 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; 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 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 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 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 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, orrepair 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, 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 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 therequirements of this AD can be accomplished.

(h) The inspections shall be done in accordance with the following British Aerospace service bulletins:

Service Bulletin Number
Revision Level

Date

S.B. 32-131
(original)
December 6, 1991
S.B. 32-131
Revision 1
November 12, 1992
S.B. 32-131
Revision 2
July 10, 1993
S.B. 32-131
Revision 3
October 18, 1995

The incorporation by reference (IBR) of certain of these service bulletins 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 follows:

Service Bulletin
Number/Revision
IBR
Approval Date
Federal Register
Citation

S.B. 32-131, (original)
January 12, 1993
(57 FR 57883, December 8, 1992)
S.B. 32-131, Revision 1
October 7, 1993
(58 FR 47036, September 7, 1993)
S.B. 32-131, Revision 2
April 6, 1995
(60 FR 12413, March 7, 1995)

The incorporation by reference of British Aerospace Service Bulletin S.B. 32-131, Revision 3, dated October 18, 1995, is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of any of these service bulletins may be obtained from British Aerospace Holding, Inc., Avro International Aerospace Division, P.O. Box 16039, Dulles International Airport, Washington DC 20041-6039. 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.

(i) This amendment becomes effective on April 21, 1997.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 93-17-04, amendment 39-8674 (58 FR 47036, September 7, 1993), and AD 95-04-06, amendment 39-9158 (60 FR 12413, March 7, 1995), which are applicable to British Aerospace Model BAe 146 and Avro 146-RJ series airplanes, was published in the Federal Register on October 18, 1996 (61 FR 54366). The action proposed to supersede AD 93-17-04 and AD 95-04-06 to continue to require either eddy current or ultra high sensitivity penetrant inspections to detect cracking of the upper main fitting of the nose landing gear (NLG), and replacement or repair of cracked parts, if necessary. It also proposed to require that inspections of certain airplanes equipped with specific NLG's be conducted at reduced intervals.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposalor the FAA's determination of the cost to the public.

Conclusion
The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact
There are approximately 52 Model BAe 146 and Model Avro 146-RJ series airplanes of U.S. registry that will 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 of the previously required actions on U.S. operators is estimated to be $9,360, or $180 per airplane, per inspection cycle.

Although this amendment adds no new actions, the associated costs for some operators will increase somewhat since certain inspections will 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 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 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. 106(g), 40113, 44701.

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), by adding a new airworthiness directive (AD), amendment 39-9969, to read as follows: