AD 99-22-03

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace BAe Model ATP airplanes, that requires repetitive inspections to detect chafing on the fuel manifold drain hose and the adjacent access panel; and corrective actions, if necessary; and installation of a protective spiral wrap on the fuel manifold drain hose. This amendment also provides for an optional terminating action for the repetitive inspections. This amendment is prompted by reports of chafing between the fuel manifold drain hose and the access panel due to contact between the two components over time. The actions specified by this AD are intended to prevent chafing within the engine nacelle, which could result in flammable fluid leaking into a zone that contains ignition sources.

Final rule

99-22-03 BRITISH AEROSPACE REGIONAL AIRCRAFT [Formerly Jetstream Aircraft Limited; British Aerospace (Commercial Aircraft) Limited]: Amendment 39-11381. Docket 99-NM-19-AD. Issued October 14, 1999.
Applicability: BAe Model ATP airplanes, except those airplanes on which British Aerospace Modification 10455A or 10455B (reference British Aerospace Service Bulletin ATP-71-15, dated December 11, 1998) has been accomplished, certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (c) of this AD. The request should include an assessment of the effect of themodification, 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 chafing within the engine nacelle, which could result in flammable fluid leaking into a zone that contains ignition sources, accomplish the following:

Repetitive Inspections and Corrective Actions
(a) Prior to the accumulation of 3,000 total flight hours, or within 1 month after the effective date of this AD, whichever occurs later, perform the actions required in paragraphs (a)(1), (a)(2), and (a)(3) of this AD in accordance with British Aerospace Alert Service Bulletin ATP-A71-14, dated November 4, 1998. Thereafter, repeat the inspections required by paragraphs (a)(1) and (a)(2) of this AD at intervals not to exceed 1,500 flight hours, until accomplishment of the actions specified in paragraph (b) of this AD.

(1) Perform an inspection of the access panel, part number (P/N) JD713J0037-000, to detect chafe damage. If any chafe damage is detected, repair the access panel in accordance with the service bulletin at the time specified in paragraph (a)(1)(i), (a)(1)(ii), or (a)(1)(iii), of this AD, as applicable.

(i) If the damage has reduced the skin thickness by 10 percent or less: Repair within 600 flight hours.

(ii) If the damage has reduced the thickness of the skin by more than 10 percent, but less than 20 percent: Repair within 100 flight hours.

(iii) If the damage has reduced the thickness of the skin by more than 20 percent: Repair prior to further flight.

(2) Perform an inspection of the fuel manifold drain hose, P/N JD007J0983-000 (C37351), to detect chafe damage. If any chafe damage is detected, either replace the fuel manifold drain hose with a new fuel manifold drain hose, P/N JD007J0983-000, in accordance with the service bulletin at the time specified in paragraph (a)(2)(i), (a)(2)(ii), or (a)(2)(iii) of this AD, as applicable; or accomplish the replacement specified in paragraph (b) of this AD. Replacement of the fuel manifold drain in accordance with paragraph (b) of this AD constitutes terminating action for the repetitive inspections required by this AD.

(i) If there are signs of worn or polished strands in the outer braid, but no strand is broken: Replace within 1,500 flight hours.

(ii) If five or less strands are broken: Replace within 300 flight hours.

(iii) If more than five strands are broken or any sign of fuel leakage exists: Replace prior to further flight.

(3) Install a protective spiral binding, P/N EFWRAP-125, on the fuel manifold drain hose.

Optional Terminating Action
(b) Replacement of the fuel manifold drain hose, P/N JD007J0983-000 (C37351), with a new, improved drain hose, P/N JD007J2377-000 (C44311), in accordance with British Aerospace Service Bulletin ATP-71-15, dated December 11, 1998, constitutes terminating action for the requirements of this AD.

Alternative Methods of Compliance
(c) 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, International Branch, ANM-116, 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, International Branch, ANM-116.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtainedfrom the International Branch, ANM-116.

Special Flight Permits
(d) 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.

Incorporation by Reference
(e) The actions shall be done in accordance with British Aerospace Alert Service Bulletin ATP-A71-14, dated November 4, 1998; or British Aerospace Service Bulletin ATP-71-15, dated December 11, 1998, as applicable. This incorporation by reference was 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 British Aerospace Regional Aircraft American Support, 13850 Mclearen Road, Herndon, Virginia 20171. 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.

(f) This amendment becomes effective on November 26, 1999.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain British Aerospace BAe Model ATP airplanes was published in the Federal Register on August 23, 1999 (64 FR 45925). That action proposed to require repetitive inspections to detect chafing on the fuel manifold drain hose and the adjacent access panel; and corrective actions, if necessary; and installation of a protective spiral wrap on the fuel manifold drain hose. That action also provides for an optional terminating action for the repetitive inspections.

Comments
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.

Correction of Address
The FAA has been informed that the title of the location where service information may be obtained has changed. The FAA has made this change in the final rule.

Conclusion
After careful review of the available data, including the change noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the change described previously. The FAA has determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact
The FAA estimates that 10 airplanes of U.S. registry will be affected by this AD.

It will take approximately 2 work hours per airplane to accomplish the required inspection on the fuel manifold drain hose and access panel, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the inspection required by this AD on U.S. operators is estimated to be $1,200, or $120 per airplane, per inspection cycle.

It will take approximately 1 work hour per airplane to accomplish the required installation of the spiral wrap on the fuel manifold drain hose, at an average labor rate of $60 per work hour. Required parts will cost approximately $10 per airplane. Based on these figures, the cost impact of the inspections required by this AD on U.S. operators is estimated to be $700, or $70 per airplane.

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.

Should an operator elect to accomplish the optional terminating option rather than continue the repetitive inspections, it will take approximately 7 work hours per airplane to accomplish the optional terminating action, at an average labor rate of $60 per work hour. Required parts will cost approximately $1,600 (pre-modification 35215A) or $2,400 (post-modification 35215A) per airplane. Based on these figures, the cost impact of this optional terminating action is estimated to be $2,020 (pre-modification 35215A) or $2,820 (post-modification 35215A) per airplane.

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 adding the following new airworthiness directive: