Airworthiness Directives; British Aerospace HP137 Mk1 and Jetstream Series 200 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 British Aerospace HP137 Mk1 and Jetstream series 200 airplanes. The proposed AD would require you to inspect the vertical stabilizer skin for disbonding, corrosion, cracks, and loose rivets, and repair any vertical stabilizer skin where discrepancies are found. 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 prevent failure of the vertical stabilizer caused by disbonding, corrosion, cracks, or loose rivets in the stabilizer skin. Such failure could lead to aircraft controllability problems.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this proposed rule on or before October 27, 2000.

ADDRESSES:

Submit comments in triplicate to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-73-AD, 901 Locust, Room 506, 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 British Aerospace Regional Aircraft, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland; telephone: (01292) 479888; facsimile: (01292) 479703. This information also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT:

Mr. S.M. Nagarajan, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4145; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on the proposed AD? The FAA invites comments on this proposed rule. You may submit whatever written data, views, or arguments you choose. You need to include the rule's docket number and submit your comments in triplicate to the address specified under the caption ADDRESSES. The FAA will consider all comments received on or before the closing date. We may amend the proposed rule in light of comments received. Factual information that supports your ideas and suggestions is extremely helpful in evaluating the effectiveness of the proposed AD action and determining whether we need to take additional rulemaking action.

Are there any specific portions of the proposed AD I should pay attention to? The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of the proposed rule that might suggest a need to modify the rule. You may examine all comments we receive before and after the closing date of the rule in the Rules Docket. We will file a report in the Rules Docket that summarizes each FAA contact with the public that concerns the substantive parts of the proposed AD.

We are re-examining the writing style we currently use in regulatory documents, in response to the Presidential memorandum of June 1, 1998. That memorandum requires federal agencies to communicate more clearly with the public. We are interested in your comments on whether the style of this document is clearer, and any other suggestions you might have to improve the clarity of FAA communications that affect you. You can get more information about the Presidential memorandum and the plain language initiative at http://www.plainlanguage.gov.

How can I be sure FAA receives my comment? If you want us to acknowledge the receipt of your comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 99-CE-73-AD.” We will date stamp and mail the postcard back to you.

Discussion

What events have caused this proposed AD? The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom, recently notified the FAA that an unsafe condition may exist on all British Aerospace HP137 Mk1 and Jetstream series 200 airplanes. The CAA reports instances of delamination and corrosion of the vertical stabilizer skin. Such damage resulted in cracks around the rivet holes.

What are the consequences if the condition is not corrected? If not detected and corrected, a damaged vertical stabilizer skin could lead to failure of the vertical stabilizer with consequent airplane controllability problems.

Is there service information that applies to this subject? British Aerospace has issued Jetstream Alert Service Bulletin 55-A-JA-990640, Issued: September 1, 1999.

What are the provisions of this service bulletin? This service bulletin:

• Includes procedures for inspecting the vertical stabilizer skin for disbonding, corrosion, cracks, and loose rivets; and
• Specifies repairing any vertical stabilizer skin where discrepancies are found in accordance with the procedures in the maintenance manual or an FAA-approved repair scheme.

What action did the CAA take? The CAA classified this service bulletin as mandatory in order to assure the continued airworthiness of these airplanes in the United Kingdom. The CAA classifying a service bulletin as mandatory is the same in the United Kingdom as the FAA issuing an AD in the United States.

Was this in accordance with the bilateral airworthiness agreement? These airplane models are manufactured in the United Kingdom and are 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 FAA informed of the situation described above.

The FAA's Determination and an Explanation of the Provisions of the Proposed AD

What has FAA decided? The FAA has examined the findings of the CAA; reviewed all available information, including the service information referenced above; and determined that:

• The unsafe condition referenced in this document exists or could develop on other British Aerospace HP137 Mk1 and Jetstream series 200 airplanes of the same type design;
• The actions specified in the previously-referenced service information should be accomplished on the affected airplanes, except for reporting any discrepancies to British Aerospace; and
• AD action should be taken in order to correct this unsafe condition.

What does the proposed AD require? This proposed AD would require you to inspect the vertical stabilizer skin for disbonding, corrosion, cracks, and loose rivets, and repair any vertical stabilizer skin where discrepancies are found.

Are there differences between the proposed AD and the Service Bulletin? British Aerospace Jetstream Alert Service Bulletin 55-A-JA-990640, Issued: September 1, 1999, specifies reporting the results of the inspections to British Aerospace Regional Aircraft. This NPRM does not specify this action. The FAA recommends that each owner/operator submit this information and we are including a note in the proposed AD to communicate this. British Aerospace and the British CAA will use this information to determine whether repetitive inspections are necessary, and, if so, at what intervals.

The FAA will evaluate the information from the British CAA and may initiate further rulemaking action to propose a repetitive inspection requirement.

Cost Impact

How many airplanes does the proposed AD impact? We estimate that the proposed AD affects 85 airplanes in the U.S. registry.

What is the cost impact of the proposed AD on owners/operators of the affected airplanes? We estimate the following costs to accomplish the proposed inspection:

Regulatory Impact

Does this proposed AD impact various entities? The regulations proposed herein would not have a substantial direct effect 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, it is determined that this proposed rule would not have federalism implications under Executive Order 13132.

Does this proposed AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this proposed 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.