Airworthiness Directives; deHavilland Inc. Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III Airplanes

[Federal Register Volume 64, Number 78 (Friday, April 23, 1999)] [Proposed Rules] [Pages 19932-19934] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-10172]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-05-AD] RIN 2120-AA64

Airworthiness Directives; deHavilland Inc. Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to adopt a new airworthiness directive (AD) that would apply to all deHavilland Inc. (deHavilland) Models DHC- 2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. The proposed AD would require repetitively inspecting the rear fuselage bulkhead at Station 228 for cracks. The proposed AD would also require repairing any crack found or replacing any cracked rear fuselage bulkhead in accordance with a repair or replacement scheme obtained from the manufacturer through the Federal Aviation Administration (FAA). The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Canada. The actions specified by the proposed AD are intended to detect and correct cracking of the rear fuselage bulkhead at Station 228, which could result in structural damage of the fuselage to the point of failure with consequent loss of airplane control.

DATES: Comments must be received on or before May 21, 1999.

ADDRESSES: Submit comments in triplicate to the FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-05- 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 Bombardier Inc., Bombardier Regional Aircraft Division, Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5; telephone: (416) 633-7310. This information also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. James Delisio, Aerospace Engineer, FAA, New York Aircraft Certification Office, 10 Fifth Street, 3rd Floor, Valley Stream, New York 11581-1200; telephone: (516) 256-7521; facsimile: (516) 568-2716.

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 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 No. 99-CE-05-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. 99-CE-05-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Discussion

Transport Canada, which is the airworthiness authority for Canada, recently notified the FAA that an unsafe condition may exist on all deHavilland Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes. Transport Canada reports three incidents of cracks found in the rear fuselage bulkhead at Station 228. The airplanes involved in these incidents had between 10,000 and 12,000 hours time-in-service (TIS). This condition, if not detected and corrected in a timely manner, could result in structural damage of the fuselage to the point of failure with consequent loss of airplane control.

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Relevant Service Information

Bombardier Inc. has issued the following service information to address the above-referenced condition:

--deHavilland Beaver Service Bulletin 2/52, dated August 30, 1998, which specifies procedures for inspecting the rear fuselage bulkhead at Station 228 for cracks on Models DHC-2 Mk. I and DHC-2 Mk. II airplanes; and --deHavilland Beaver Service Bulletin TB/60, dated August 30, 1998, which specifies procedures for inspecting the rear fuselage bulkhead at Station 228 for cracks on Model DHC-2 Mk. III airplanes.

Transport Canada classified these service bulletins as mandatory and issued Canadian AD No. CF-98-38, dated October 15, 1998, in order to assure the continued airworthiness of these airplanes in Canada.

The FAA's Determination

This airplane model is manufactured in Canada 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, Transport Canada has kept the FAA informed of the situation described above. The FAA has examined the findings of Transport Canada; 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 deHavilland Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III airplanes of the same type design registered in the United States, the FAA is proposing AD action. The proposed AD would require the following:

--Repetitively inspecting the rear fuselage bulkhead at Station 228 for cracks in accordance with the previously referenced service information; and --Repairing any crack found or replacing any cracked rear fuselage bulkhead in accordance with a repair or replacement scheme obtained from the manufacturer through the FAA.

Compliance Time of the Proposed AD

The compliance time of the proposed AD is presented in both calendar time and hours TIS. While cracks are generally a result of classic fatigue (i.e., aging and cylic operation), the FAA and Bombardier believe that the condition could develop over time regardless of how often the airplane is operated. In order to assure that rear fuselage bulkhead cracking does not go undetected, a compliance time of specific hours TIS and calendar time (whichever occurs first) is proposed.

Cost Impact

The FAA estimates that 350 airplanes in the U.S. registry would be affected by the proposed AD, that it would take approximately 1 workhour per airplane to accomplish the proposed initial 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 $21,000, or $60 per airplane. These figures only take into the account the costs of the initial inspection and do not take into account the costs of the repetitive inspections or the cost of any repair or replacement necessary if any rear fuselage bulkhead was found cracked. The FAA has no way of determining the number of repetitive inspections each owner/operator would incur over the life of his/her affected airplane or the number of airplanes that would have a cracked rear fuselage bulkhead and need repair or replacement.

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:

deHavilland Inc. Docket No. 99-CE-05-AD.

Applicability: Models DHC-2 Mk. I, DHC-2 Mk. II, and DHC-2 Mk. III 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 (d) 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 cracking of the rear fuselage bulkhead at Station 228, which could result in structural damage of the fuselage to the point of failure with consequent loss of airplane control, accomplish the following: (a) Within the next 400 hours time-in-service (TIS) after the effective date of this AD or within the next 12 calendar months after the effective date of this AD, whichever occurs first, and thereafter at intervals not to exceed 2,000 hours TIS or 5 years, whichever occurs first, inspect the rear fuselage bulkhead at Station 228 for cracks. Inspect in accordance with the Accomplishment Instructions section of whichever of the following service bulletins that is applicable: (1) For the Models DHC-2 Mk. I and DHC-2 Mk. II airplanes: deHavilland Beaver

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Service Bulletin 2/52, dated August 30, 1998; or (2) For the Model DHC-2 Mk. III airplanes: deHavilland Beaver Service Bulletin TB/60, dated August 30, 1998. (b) If any crack(s) is/are found in the rear fuselage bulkhead at Station 228 during any inspection required by paragraph (a) of this AD, prior to further flight, accomplish the following: (1) Obtain a repair or replacement scheme from the manufacturer through the FAA, New York Aircraft Certification Office (ACO), 10 Fifth Street, 3rd Floor, Valley Stream, New York 11581-1200; facsimile: (516) 568-2716. (2) Incorporate this repair or replacement scheme. (c) 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. (d) 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, New York Aircraft ACO, 10 Fifth Street, 3rd Floor, Valley Stream, New York 11581-1200. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO.

Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO.

(e) Questions or technical information related to deHavilland Beaver Service Bulletin TB/60, dated August 30, 1998, and deHavilland Beaver Service Bulletin 2/52, dated August 30, 1998, should be directed to Bombardier Inc., Bombardier Regional Aircraft Division, Garratt Boulevard, Downsview, Ontario, Canada M3K 1Y5; telephone: (416) 633-7310. 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 Canadian AD No. CF-98-38, dated October 15, 1998.

Issued in Kansas City, Missouri, on April 15, 1999. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-10172 Filed 4-22-99; 8:45 am] BILLING CODE 4910-13-P