Airworthiness directives: Short Brothers and Harland Ltd.,

[Federal Register: September 28, 1999 (Volume 64, Number 187)]

[Proposed Rules]

[Page 52263-52265]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr28se99-21]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-99-AD]

RIN 2120-AA64

Airworthiness Directives; Short Brothers and Harland Ltd. Models SC-7 Series 2 and SC-7 Series 3 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: This document proposes to adopt a new airworthiness directive (AD) that would apply to all Short Brothers and Harland Ltd. (Shorts) Models SC-7 Series 2 and SC-7 Series 3 airplanes. The proposed AD would require repetitively inspecting the wing attachment bushes in the fuselage front and rear spar frames for migration (gaps), and replacing the bushes if a gap exists that is of a certain length or more. The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by the proposed AD are intended to detect and correct migration of the wing attachment bushes in the fuselage front and rear spar frames, which could result in structural damage to the wing spar/fuselage fitting with possible loss of control of the airplane.

DATES: Comments must be received on or before November 3, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 97-CE-99-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. Comments may be inspected at this location between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted.

Service information that applies to the proposed AD may be obtained from Short Brothers plc, P.O. Box 241, Airport Road, Belfast BT3 9DZ, Northern Ireland. This information also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. Roger Chudy, Aerospace Engineer, FAA, Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, Missouri 64106; telephone: (816) 426-6932; facsimile: (816) 426-2169.

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 should 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 that summarizes each FAA-public contact concerned with the substance of this proposal will be filedin 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 No. 97-CE-99-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, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 97-CE-99-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Discussion

The Civil Airworthiness Authority (CAA), which is the airworthiness authority for the United Kingdom, recently notified the FAA that an unsafe condition may exist on all Shorts Models SC-7 Series 2 and SC-7 Series 3 airplanes. The CAA reports migration in the wing attachment bushes in the fuselage front and rear spar frames.

If the migration is not detected and corrected in a timely manner, then gaps will occur in these areas. Once a gap exists that is of a certain length, structural damage to the wing spar/fuselage fitting could occur. This could eventually result in loss of control of the airplane.

Relevant Service Information

Short Brothers & Harland Ltd. issued Shorts Service Bulletin 53-68, which specifies procedures for inspecting the wing attachment bushes in the fuselage front and rear spar frames for migration (gaps), and replacing the bushes if a gap exists that is of a certain length or more. Shorts Service Bulletin No. 53-68 incorporates the following pages:

Pages

Revision level

Date

6, 7, 8, 9, 10, 13, 14, 17, Original Issue. January 10, 1996. 18, 19, 20, 21, 22, 23, 24, and 25. 12.......................... Revision No: 1. May 30, 1996. 3........................... Revision No: 2. September 1998. 1, 2, 4, 5, 11, 15, and 16.. Revision No: 3. May 1999.

The CAA classified this service bulletin as mandatory and issued British Airworthiness Directive 009-01-96, not dated, in order to assure the continued airworthiness of these airplanes in the United Kingdom.

[[Page 52264]]

The FAA's Determination

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, including the service information referenced above; and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of the Provisions of the Proposed AD

Since an unsafe condition has been identified that is likely to exist or develop in other Shorts Models SC-7 Series 2 and SC-7 Series 3 airplanes of the same type design registered in the United States, the FAA is proposing AD action. The proposed AD would require repetitively inspecting the wing attachment bushes in the fuselage front and rear spar frames for migration (gaps), and replacing the bushes if a gap exists that is of a certain length or more. Accomplishment of the proposed action would be required in accordance with Shorts Service Bulletin 53-68.

Cost Impact

The FAA estimates that 22 airplanes in the U.S. registry would be affected by the proposed initial inspection, that it would take approximately 10 workhours per airplane to accomplish the proposed inspection, and that the average labor rate is approximately $60 an hour. Based on these figures, the total cost impact of the proposed initial inspection on U.S. operators is estimated to be $13,200, or $600 per airplane.

These figures only take into account the cost of the initial inspections and do not account for the cost of repetitive inspections or the cost necessary to replace any bushings when gaps that exceed a certain length are found. The FAA has no way of determining the number of repetitive inspections or replacements each owner/operator will incur over the life of the affected airplanes.

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 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) 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 has been placed 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 adding a new airworthiness directive (AD) to read as follows:

   Short Brothers and Harland Ltd.: Docket No. 97-CE-99-AD.

   Applicability: Models SC-7 Series 2 and SC-7 Series 3 airplanes, all serial numbers, 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 in the body of this AD, unless already accomplished.

   To detect and correct migration of the wing attachment bushes in the fuselage front and rear spar frames, which could result in structural damage to the wing, accomplish the following:

   (a) Within the next 100 hours time-in-service (TIS) after the effective date of this AD, and thereafter as indicated in the paragraphs below (depending on the inspection results), inspect the wing attachment bushes in the fuselage front and rear spar frames for migration. Accomplish this inspection in accordance with Shorts Service Bulletin No. 53-68, which incorporates the following pages:

   Pages

   Revision level

   Date

   6, 7, 8, 9, 10, 13, 14, 17, Original Issue. January 10, 1996. 18, 19, 20, 21, 22, 23, 24, and 25. 12.......................... Revision No: 1. May 30, 1996. 3........................... Revision No: 2. September 1998. 1, 2, 4, 5, 11, 15, and 16.. Revision No: 3. May 1999.

   (b) If no gaps are found at the bush areas during any inspection required by this AD, repeat the inspection specified in paragraph (a) of this AD at intervals not to exceed 500 hours.

   (c) If any gap is found at the bush area that is less than 0.125 inches in length during any inspection required by this AD, repeat the inspection specified in paragraph (a) of this AD at intervals not to exceed 100 hours TIS provided the gaps do not increase to 0.125 inches or more in length. If the gap has not increased during 3 additional inspections and continue to not increase, then the inspection intervals may be increased to 500 hours TIS.

   (d) If any gap is found at the bush areas that is 0.125 inches or more in length during any inspection required by this AD, prior to further flight, replace the bushes with parts specified in and in accordance with Shorts Service Bulletin 53-68. Inspect the replacement bushes at intervals not to exceed

   [[Page 52265]]

   500 hours TIS (in accordance with paragraph (a) of this AD).

   (e) 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.

   (f) An alternative method of compliance or adjustment of the initial or repetitive compliance times that provides an equivalent level of safety may be approved by the Manager, Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, Missouri 64106. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

   Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate.

   (g) Questions or technical information related to Shorts Service Bulletin 53-68 should be directed to Short Brothers plc, P.O. Box 241, Airport Road, Belfast BT3 9DZ, Northern Ireland. This service information may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

   Note 3: The subject of this AD is addressed in British Airworthiness Directive 009-01-96, not dated.

   Issued in Kansas City, Missouri, on September 21, 1999. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 99-25221Filed9-27-99; 8:45 am]

   BILLING CODE 4910-13-U