01-16053. Airworthiness Directives; Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 series airplanes. This proposal would require a one-time eddy current inspection for cracks of the fuselage butt joint which is forward of the emergency exits on the left- and right-hand sides of the airplane at the level of stringers 27/48. This proposal would also require repair of any cracks detected. This action is prompted by issuance of mandatory continuing airworthiness information by a foreign airworthiness authority. This action is necessary to detect and correct cracks in the area of the emergency escape hatches, which, if undetected, could result in depressurization during flight, possibly leading to structural failure of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by July 27, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket Number 2001-NM-23-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-23-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Fokker Services B.V., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Tom Rodriguez, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

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 shall 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 action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

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 summarizing 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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2001-NM-23-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, Transport Airplane Directorate, ANM-114, Attention: Rules Docket Number 2001-NM-23-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Rijksluchtvaartdienst (RLD), which is the airworthiness authority for the Netherlands, notified the FAA that a crack was found in the fuselage skin in a bonded doubler at stringer 48 during regular maintenance of a Model F.28 Mark 1000 series airplane. The airplane had accumulated 56,000 total flight cycles when the crack was discovered. Subsequent investigation revealed that the crack began at a scratch, which may have occurred during production, on the bonded doubler at the edge of the bonded lower skin. This condition, if not corrected, could result in depressurization during flight, possibly leading to structural failure of the airplane.

Explanation of Relevant Service Information

Fokker has issued Service Bulletin SBF28/53-148, dated August 15, 2000, which describes procedures for conducting a one-time eddy current inspection for cracks of the fuselage butt joint forward of the emergency exits on the left- and right-hand sides of the airplane at the level of stringers 27/48 and reporting the findings to Fokker. The RLD classified this service bulletin as mandatory and issued Dutch airworthiness directive 2000-151, dated November 30, 2000, in order to assure the continued airworthiness of these airplanes in the Netherlands. If any cracks are found as a result of the inspection, repair is to be conducted in a manner approved by the FAA or the RLD.

FAA's Conclusions

These airplane models are manufactured in the Netherlands and are type certificated for operation in the United States under the provisions of § 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the RLD has kept the FAA informed of the situation described above. The FAA has examined the findings of the RLD, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously, except as discussed below. The proposed AD also would require reporting of the results (positive or negative) to the FAA.

Differences Between Proposed Rule and Foreign Airworthiness Directive

Operators should note that, although the Dutch airworthiness directive specifies that the manufacturer may be contacted for disposition of certain repair conditions, this proposal would require the repair of those conditions to be accomplished per a method approved by either the FAA or the RLD (or a delegated agent of the RLD). In light of the type of repair that would be required to address the identified unsafe condition, and in consonance with existing bilateral airworthiness agreements, the FAA has determined that, for this proposed AD, a repair approved by either the FAA or the RLD would be acceptable for compliance with this proposed AD.

Cost Impact

The FAA estimates that 23 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 2 work hours per airplane to accomplish the proposed eddy current inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $2,760, or $120 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

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 proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the 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 is contained 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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Fokker Services B.V.: Docket 2001-NM-23-AD.

Applicability: All Model F.28 Mark 1000, 2000, 3000, and 4000 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 (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, unless accomplished previously.

To detect and correct cracks in the area of the emergency escape hatches, which, if undetected, could result in depressurization during flight, possibly leading to structural failure of the airplane, accomplish the following:

Inspection

(a) Prior to the accumulation of 30,000 total flight cycles, or within 12 months after the effective date of this AD, whichever occurs later: Perform a one-time eddy current inspection to detect cracks of the fuselage butt joint forward of the emergency hatches on the left- and right-hand sides of the airplane at the level of stringers 27/48, in accordance with the Accomplishment Instructions of Fokker Service Bulletin SBF28/53-148, dated August 15, 2000.

Repair

(b) If any crack is found during the inspection required by paragraph (a) of this AD: Prior to further flight, repair the crack per a method approved by either the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate; or the Rijksluchtvaartdienst (or its delegated agent).

Reporting

(c) Submit a report of inspection findings (both positive and negative) to Fokker Services B.V., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands; and to Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; fax [phone]. The report is to be submitted at the applicable time specified in paragraph (c)(1) or (c)(2) of this AD. The report must include the inspections results, a description of any discrepancies found, the airplane serial number, and the number of landings and flight hours on the airplane. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB control Number 2120-0056.

(1) For airplanes on which the inspection is accomplished after the effective date of this AD: Submit a report of findings within 10 days after performing the inspection required by paragraph (a) of this AD.

(2) For airplanes on which the inspection was accomplished prior to the effective date of this AD: Submit a report of findings within 10 days after the effective date of this AD.

Alternative Methods of Compliance

(d) 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. 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 obtained from the International Branch, ANM-116.

Special Flight Permits

(e) Special flight permits may be issued in accordance with §§ 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.

Issued in Renton, Washington, on June 20, 2001.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.