Airworthiness directives: Fokker,
[Federal Register: May 20, 1999 (Volume 64, Number 97)]
[Proposed Rules]
[Page 27480-27483]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20my99-10]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-329-AD]
RIN 2120-AA64
Airworthiness Directives; Fokker Model F.28 Mark 0070 and 0100 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: This document proposes the supersedure of an existing airworthiness directive (AD), applicable to all Fokker Model F.28 Mark 0070 and 0100 series airplanes, that currently requires Airplane Flight Manual (AFM) and maintenance program revisions, modifications, and repetitive checks associated with ensuring the integrity of the thrust reverser system. That AD was prompted by results of a review, which indicated that a potential latent failure of the secondary lock actuator switch 1 of the thrust reverser system in the open position may occur, in addition to the potential failure of the secondary lock relay 1 in the energized position. This proposed AD would continue to require the modifications and repetitive checks, and would add an AFM revision, repetitive operational tests, and other modifications related to the thrust reverser system. The new modifications would terminate the repetitive operational checks and tests. The actions specified by the proposed AD are intended to ensure protection against inadvertent deployment of the thrust reversers during flight, which could result in reduced controllability of the airplane.
DATES: Comments must be received by June 21, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-329-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 Fokker Services B.V., Technical Support Department, P.O. Box 75047, 1117 ZN Schiphol Airport, the Netherlands. 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 98-NM-329-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. 98-NM-329-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.
Discussion
On December 20, 1996, the FAA issued AD 96-26-03, amendment 39-9866 (62 FR 604, January 6, 1997), applicable to all Fokker Model F.28 Mark 0070 and 0100 series airplanes, to require a revision to the Airplane Flight Manual (AFM) to enable the flightcrew to determine if the thrust reversers are properly stowed and locked prior to take-off. In addition, that AD requires a revision to the maintenance program to incorporate instructions to perform checks of the thrust reverser system and correct thrust reverser malfunctions. That AD also requires modifications that serve as terminating actions for the revisions to the AFM and maintenance program, and repetitive checks of the thrust reverser system. That action was prompted by results of a review, which indicated that a potential latent failure of the secondary lock actuator switch 1 of the thrust reverser system in the open position may occur, in addition to the potential latent failure of the secondary lock relay 1 in the energized position. The requirements of that AD are intended to ensure protection against inadvertent deployment of the thrust reversers during flight.
Actions Since Issuance of Previous Rule
In the preamble to AD 96-26-03, the FAA specified that the actions required by that AD were considered to be interim action and that the manufacturer would develop a modification to positively address the unsafe condition. The FAA indicated that it may consider further rulemaking action once a modification was developed, approved, and available. The manufacturer now has developed such a modification, and the FAA has determined that further rulemaking action is indeed necessary; this proposed AD follows from that determination.
[[Page 27481]]
Relevant Service Information
Fokker has issued Service Bulletin SBF100-78-014, Revision 1, dated December 15, 1998, as revised by Change Notice 1, dated December 18, 1998, and Change Notices 2 and 3, both dated January 29, 1999. This service bulletin describes procedures for modification of the thrust reverser electrical control system and thrust reverser indication and warning system. This modification involves connecting both systems to the emergency direct current (DC) bus, and installing a new relay panel, relays, and electrical circuits.
Fokker also has issued Component Service Bulletins P41440-78-04 and P41440-78-05, both dated August 15, 1998, which describe procedures for modification of the aft engine cowlings. This modification involves removing the cover of the terminal block (for certain airplanes, a new cover must be installed), re-routing the electrical wiring of the terminal block (on the side of the thrust reverser), and installing a voltage spike protection diode assembly to the thrust reverser wiring.
In addition, Fokker 70/100 Airplane Maintenance Manual 78-32-01, dated June 1, 1998, describes procedures for repetitive operational tests of the pilot valve and piston seal for leakage of the selector valve of the thrust reversers.
Accomplishment of these service documents is intended to adequately address the identified unsafe condition. The Rijksluchtvaartdienst (RLD), which is the airworthiness authority for the Netherlands, classified these service bulletins as mandatory and issued Dutch airworthiness directive BLA 1996-140/2, dated August 31, 1998, in order to assure the continued airworthiness of these airplanes in the Netherlands.
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 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 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 supersede AD 96-26-03 to continue to require accomplishment of modifications of the wiring of the electrical control, and indication and warning systems of the thrust reversers, and repetitive operational checks of the thrust reverser system. This proposed AD would add requirements for a revision to the Abnormal Procedures section of the FAA-approved AFM to provide the flightcrew with operating procedures in the event that an unlocked thrust reverser alert occurs. This proposed AD also would require repetitive operational tests of the pilot valve and piston seal, for leakage of the selector valve of the thrust reversers. In addition, this proposed AD would require modification of the thrust reverser electrical control system and thrust reverser indication and warning system, and modification of the aft engine cowlings, which, when accomplished, would terminate the repetitive operational checks and tests. The actions would be required to be accomplished in accordance with the service documents described previously, except as discussed below.
Differences Between This Proposed AD and Service Information
Operators should note that the Fokker 70/100 Airplane Maintenance Manual does not specify corrective actions if any discrepancy is detected during any operational test of the pilot valve and piston seal for leakage of the selector valve of the thrust reversers. This proposal would require repair of any discrepancy to be accomplished in accordance with a method approved by either the FAA or the RLD (or its delegated agent). 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
There are approximately 131 airplanes of U.S. registry that would be affected by this proposed AD.
The actions that are currently required by AD 96-26-03 take approximately 20 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts cost approximately $1,200 per airplane. Based on these figures, the cost impact of the currently required actions on U.S. operators is estimated to be $314,400, or $2,400 per airplane.
The new AFM revision that is proposed in this AD action would take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the AFM revision proposed by this AD on U.S. operators is estimated to be $7,860, or $60 per airplane.
The new operational tests that are proposed in this AD action would take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the operational tests proposed by this AD on U.S. operators is estimated to be $7,860, or $60 per airplane, per test cycle.
The new modifications that are proposed in this AD action would take approximately 10 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts would cost approximately $7,737 per airplane. Based on these figures, the cost impact of the modifications proposed by this AD on U.S. operators is estimated to be $1,092,147, or $8,337 per airplane.
The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the current or proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.
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
[[Page 27482]]
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
-
The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
-
Section 39.13 is amended by removing amendment 39-9866 (62 FR 604, January 6, 1997), and by adding a new airworthiness directive (AD), to read as follows:
Fokker Services B.V.: Docket 98-NM-329-AD. Supersedes AD 96-26-03, Amendment 39-9866.
Applicability: All Model F.28 Mark 0070 and 0100 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 (h)(1) 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 ensure protection against inadvertent deployment of the thrust reversers during flight, which could result in reduced controllability of the airplane, accomplish the following:
Restatement of Certain Requirements of AD 96-26-03, Amendment 39- 9866
(a) Within 60 days after January 21, 1997 (the effective date of AD 96-26-03, amendment 39-9866), modify the wiring of the electrical control, and indication and warning systems of the thrust reversers, in accordance with Fokker Service Bulletin SBF100-78-012, dated November 22, 1996.
(b) For Model F.28 Mark 0070 series airplanes: Prior to or in conjunction with the accomplishment of paragraph (a) of this AD, modify the wiring of the priority switching of the emergency inverter power supply in accordance with Fokker Service Bulletin SBF100-24-034, Revision 1, dated September 12, 1996.
(c) Within 500 flight cycles following accomplishment of paragraph (a) of this AD, perform operational checks to detect failures of the secondary lock actuator, primary lock switch, indication and warning system, and feedback cable mechanism of the thrust reversers in accordance with Fokker Service Bulletin SBF100- 78-013, dated November 22, 1996. If any failure is detected, prior to further flight, repair the thrust reverser system in accordance with Chapter 78-30-00 of the Fokker Airplane Maintenance Manual. Repeat the operational checks thereafter at intervals not to exceed 500 flight cycles.
New Requirements of This AD
Airplane Flight Manual (AFM) Revision
(d) Within 3 months after the effective date of this AD, revise the Abnormal Procedures Section, Sub-section Engine, of the FAA- approved AFM to include the following information. This may be accomplished by inserting a copy of this AD in the AFM.
Reverser Unlocked Procedure on Ground (Except During Engine Start)
Reverser system........................... Maintenance action required
Note: If alert occurs during engine start, recycle affected reverser after engine start.
In Flight
Note: If thrust lever is not blocked at idle and no pronounced buffet is present, normal operation of the aircraft may be continued, although alert may persist. After landing, maintenance action is required.
ATS....................................... (Check) Disconnect Affected thrust lever..................... (Check) Idle Speed..................................... Max 200 kts Affected fuel lever....................... Shut Single engine procedure................... Apply
Note: Descent below 1,000 feet AGL requires that the landing be completed.
Repetitive Tests
(e) Perform an operational test of the pilot valve and piston seal for leakage of the selector valve of the thrust reversers, in accordance with Fokker 70/100 Airplane Maintenance Manual 78-32-01, dated June 1, 1998, at the latest of the times specified in paragraphs (e)(1), (e)(2), and (e)(3) of this AD. If any discrepancy is detected, prior to further flight, repair in accordance with a method approved by either the Manager, International Branch, ANM- 116, FAA, Transport Airplane Directorate; or the RLD (or its delegated agent). Repeat the operational test thereafter at intervals not to exceed 12,000 flight hours.
(1) For airplanes on which Fokker Service Bulletin SBF100-78- 004, Revision 1, dated November 22, 1996, has been accomplished prior to the effective date of this AD: Within 12,000 flight hours after accomplishment of Fokker Service Bulletin SBF100-78-004, Revision 1, dated November 22, 1996.
(2) Within 6,000 flight hours after accomplishment of Fokker Service Bulletin SBF100-78-012, dated November 22, 1996.
(3) Within 500 flight hours after the effective date of this AD.
Terminating Modifications
(f) Within 18 months after the effective date of this AD, concurrently accomplish the requirements of paragraphs (f)(1) and (f)(2) of this AD. Accomplishment of these modifications constitutes terminating action for the repetitive operational checks and operational tests required by paragraphs (c) and (e) of this AD.
(1) Modify the thrust reverser electrical control system and thrust reverser indication and warning system, in accordance with Fokker Service Bulletin SBF100-78-014, Revision 1, dated December 15, 1998; as revised by Change Notice 1, dated December 18, 1998, and Change Notices 2 and 3, both dated January 29, 1999.
(2) Modify the aft engine cowlings in accordance with Fokker Component Service Bulletins P41440-78-04 and P41440-78-05, both dated August 15, 1998.
Spares
(g) As of the effective date of this AD, no person shall install on any airplane an aft engine cowling having part number 1159P41440, unless it has been modified in accordance with paragraph (f)(2) of this AD.
Alternative Methods of Compliance
(h)(1) 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.
(h)(2) Alternative methods of compliance, approved previously in accordance with AD 96-26-03, amendment 39-9866 for accomplishment of paragraph (c) of that AD, are approved as alternative methods of compliance with paragraph (a) of this AD.
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
(i) 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 Dutch airworthiness directive BLA 1996-140/2, dated August 31, 1998.
[[Page 27483]]
Issued in Renton, Washington, on May 13, 1999. D.L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 99-12689Filed5-19-99; 8:45 am]
BILLING CODE 4910-13-P
