Airworthiness directives: Dornier,

[Federal Register: June 9, 1998 (Volume 63, Number 110)]

[Proposed Rules]

[Page 31382-31384]

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

[DOCID:fr09jn98-27]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-113-AD]

RIN 2120-AA64

Airworthiness Directives; Dornier Model 328-100 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY: This document revises an earlier proposed airworthiness directive (AD), applicable to certain Dornier Model 328-100 series airplanes, that would have required repetitive inspections to detect cracking of the support beam of the main landing gear (MLG) fairing; and permanent repair of any cracking found, which would terminate the repetitive inspections. This new action revises the proposed rule by adding a requirement for installation of reinforcement parts for the longitudinal beam of the MLG fairing, which also would terminate the repetitive inspections. This new action also limits the applicability of the proposed rule. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this new proposed AD are intended to prevent cracking of the support beam of the MLG fairing, which could result in reduced structural integrity of the lower part of the MLG fairing, and consequent separation of part of the fairing from the airplane and possible damage to the airplane or injury to persons on the ground.

DATES: Comments must be received by July 6, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 96-NM-113-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from FAIRCHILD DORNIER, DORNIER Luftfahrt GmbH, P.O. Box 1103, D-82230 Wessling, Germany. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

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 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 summarizing 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 Number 96-NM-113-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 No. 96-NM-113-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain Dornier Model 328-100 series airplanes, was published as a notice of proposed rulemaking (NPRM) in the Federal Register on April 9, 1997 (62 FR 17129). That NPRM would have required repetitive inspections to detect cracking of the support beam of the main landing gear (MLG) fairing; and permanent repair of any cracking found, which would terminate the repetitive inspections. That NPRM was prompted by reports of cracking of the support beam of the MLG fairing. That condition, if not corrected, could result in reduced structural integrity of the lower part of the MLG fairing, and consequent separation of part of the fairing from the airplane and possible damage to the airplane or injury to persons on the ground.

Disposition of Comments

Due consideration has been given to the comments received in response to the NPRM.

Request To Cite Additional Service Information

One commenter, the manufacturer, requests that the FAA revise the proposal to reference Dornier Service Bulletin SB-328-53-184, Revision 1, dated July 2, 1997. That service bulletin describes procedures for installation of reinforcement parts for the longitudinal beam of the MLG fairing, which would eliminate the need for the repetitive inspections. The effectivity listing of the service bulletin limits accomplishment of the installation of reinforcement parts to those airplanes on which the installation was not accomplished in production. Accomplishment of the action specified in the service bulletin is intended to adequately address the identified unsafe condition. The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, classified the original release of this service bulletin, dated January 10, 1997, as mandatory and issued German airworthiness directive 97-073, dated March 27, 1997, in order to assure the continued airworthiness of these airplanes in Germany.

The FAA concurs with the commenter's request. The FAA finds that accomplishment of the terminating action is necessary within 3,000 hours time-in-service, as specified in the German airworthiness directive. The FAA has revised this supplemental NPRM accordingly. Additionally, the cost impact information, below, has been revised to reflect any additional costs to operators.

[[Page 31383]]

Request To Revise Compliance Time

The manufacturer requests that the FAA consider adjusting the compliance time specified in paragraph (a)(2) of the proposed AD to provide an option for temporary repair if cracks less than 50 mm are found, and to allow a repetitive inspection every 300 flight hours until the crack length exceeds 50 mm, as recommended in Dornier Alert Service Bulletin ASB-328-53-010, dated October 13, 1995. The commenter states that the request is based on the work hours required to accomplish the installation of reinforcement parts (as described in Dornier Service Bulletin SB-328-53-184) and the availability of mod kits. Additionally, the commenter notes that this option for temporary repair would provide relief for operators to continue revenue flight until arrival at a suitable maintenance facility.

The FAA does not concur. As stated in the original NPRM, the FAA has determined that, due to the safety implications and consequences associated with such cracking, the permanent repair would be required to be accomplished prior to further flight, if evidence of cracking is found. This supplemental NPRM also adds a requirement for installation of reinforcement parts within 3,000 hours time-in-service, which would terminate the requirement for the repetitive inspections; this installation can be accomplished prior to any finding of cracks, and so may be more easily scheduled at the operator's convenience. Additionally, under the provisions of paragraph (d) of this supplemental NPRM, the FAA may approve requests for adjustments to the compliance time if data are submitted to substantiate that such an adjustment would provide an acceptable level of safety.

Conclusion

Since the change described previously expands the scope of the originally proposed rule, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Cost Impact

The FAA estimates that 47 Dornier Model 328-100 series airplanes of U.S. registry would be affected by this proposed AD.

It would take approximately 1 work hour per airplane to accomplish the proposed inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the inspection proposed by this AD on U.S. operators is estimated to be $2,820, or $60 per airplane, per inspection cycle.

It would take approximately 8 work hours per airplane to accomplish the proposed installation of reinforcement parts, and that the average labor rate is $60 per work hour. Required parts would be supplied by the manufacturer at no cost to the operators. Based on these figures, the cost impact of the installation proposed by this AD on U.S. operators is estimated to be $22,560, or $480 per airplane.

The cost impact figures discussed above are 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 AD were not adopted.

Should an operator be required to accomplish the permanent repair of cracked structure, it would take approximately 3 work hours per airplane to accomplish it, at an average labor rate of $60 per work hour. Required parts would be supplied by the manufacturer at no cost to the operators. Based on these figures, the cost impact of the repair action, if accomplished, is estimated to be $180 per airplane.

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 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.

   Sec. 39.13 [Amended]

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

   Dornier Luftfahrt GmbH: Docket 96-NM-113-AD.

   Applicability: Model 328-100 series airplanes, serial numbers 3005, 3008, 3009, and 3011 through 3079 inclusive; 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 (c) 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 prevent reduced structural integrity of the lower part of the main landing gear (MLG) fairing, and consequent separation of part of the fairing from the airplane and possible damage to the airplane or injury to persons on the ground, accomplish the following:

   (a) Within 300 hours time-in-service after the effective date of this AD, perform a visual inspection to detect cracking of the lower attachment flanges in the area of the bend radii of the forward and aft support beams of the MLG, in accordance with Dornier Alert Service Bulletin ASB-328-53-010, dated October 13, 1995.

   (1) If no cracking is found, repeat the inspection thereafter at intervals not to exceed 300 hours time-in-service, until the actions required by either paragraph (a)(2) or (b) of this AD have been accomplished.

   (2) If any cracking is found, prior to further flight, accomplish the permanent repair in accordance with the alert service bulletin. Accomplishment of the permanent repair constitutes terminating action for the repetitive inspections required by this AD.

   (b) Within 3,000 hours time-in-service after the effective date of this AD, install reinforcement parts for the longitudinal beam

   [[Page 31384]]

   of the MLG, in accordance with Dornier Service Bulletin SB-328-53- 184, Revision 1, dated July 2, 1997. Accomplishment of this installation constitutes terminating action for the requirements of this AD.

   (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 obtained from the International Branch, ANM-116.

   (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.

   Note 3: The subject of this AD is addressed in German airworthiness directives 95-413, dated November 2, 1995, and 97-073, dated March 27, 1997.

   Issued in Renton, Washington, on June 3, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-15247Filed6-8-98; 8:45 am]

   BILLING CODE 4910-13-U