AD 99-18-19

This amendment adopts a new airworthiness directive (AD) that is applicable to General Electric Company CF6-80A1/A3 and CF6-80C2A series turbofan engines, installed on Airbus Industrie A300-600 and A310 series airplanes. This action requires, prior to further flight, one of the following: (1) performing a DPV pressure check for leakage, and, if necessary, replacing the DPV assembly with a serviceable assembly and performing an operational check of the thrust reverser, or deactivating the thrust reverser; or (2) replacing the directional pilot valve (DPV) assembly with a serviceable assembly and performing an operational check of the thrust reverser. Thereafter, this AD requires one of these actions on a repetitive basis. If a thrust reverser is deactivated, this action requires, prior to further flight, revising the FAA-approved airplane flight manual (AFM) to require performance penalties to be applied for certain takeoff conditions. The AD also requires a revision to theEmergency Procedures Section of the FAA approved AFM to include a flightcrew operational procedure in the event of any indication of an in-flight thrust reverser deployment. This amendment is prompted by review of thrust reverser safety analyses following a report of inadvertent thrust reverser deployment on another make and model engine. The actions specified in this AD are intended to prevent inadvertent thrust reverser deployment, which, if it occurred in-flight, could result in loss of control of the airplane.

Final rule; request for comments.

99-18-19 GENERAL ELECTRIC COMPANY: Amendment 39-11285. Docket 99-NE-41-AD. Issued August 26, 1999.
Applicability: General Electric Company (GE) CF6-80A1/A3 and CF6-80C2A series turbofan engines, installed on Airbus Industrie A300-600 and A310 series airplanes.
NOTE 1: This airworthiness directive (AD) applies to each engine 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 engines 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) 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 inadvertent thrust reverser deployment, which, if it occurred in-flight, could result in loss of control of the airplane, accomplish the following:
GE CF6-80A1/A3 Series Engines
(a) Prior to further flight, for GE CF6-80A1/A3 series engines, perform one of the following, in accordance with Paragraphs 2.B and 2.C. of the Accomplishment Instructions of Middle River Aircraft Systems Alert Service Bulletin (ASB) No. 78A4022, dated June 4, 1999:
(1) Perform a DPV pressure check for leakage, and, if necessary, either
(i) Replace the directional pilot valve (DPV) assembly with a serviceable assembly and then perform an operational check of the thrust reverser, or
(ii) Deactivate the thrust reverser in accordance with paragraph 2(B)(8)(a) of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A4022, dated June 4, 1999, provided, however, that within 10 days after deactivation the DPV is replaced with a serviceable assembly and an operational check of the thrust reverser is then performed.
(2) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser.
(b) Thereafter, at intervals not to exceed 700 hours time-in-service (TIS) since the last check or replacement of the DPV, for GE CF6-80A1/A3 series engines, perform one of the following, in accordance with Paragraphs 2.B and 2.C. of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A4022, dated June 4, 1999:
(1) Perform a DPV pressure check for leakage, and, if necessary, either
(i) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser, or
(ii) Deactivate the thrust reverser in accordance with paragraph 2(B)(8)(a) of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A4022, dated June 4, 1999, provided, however, that within 10 days after deactivation the DPV is replaced with a serviceable assembly and an operational check of the thrust reverser is then performed.
(2) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser.
GE CF6-80C2A Series Engines
(c) Prior to further flight, for GE CF6-80C2A series engines, perform one of the following, in accordance with Paragraphs 2.B and 2.C. of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A1081, dated June 4, 1999:
(1) Perform a DPV pressure check for leakage, and, if necessary, either
(i) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser, or
(ii) Deactivate the thrust reverser in accordance with paragraph 2(B)(8)(a) of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A1081, dated June 4, 1999, provided, however, that within 10 days after deactivation the DPV is replaced with a serviceable assembly and an operational check of the thrust reverser is then performed.
(2) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser.
(d) Thereafter, at intervals not to exceed 700 hours TIS since the last check or replacement of the DPV, for GE CF6- 80C2A series engines, perform one of the following, in accordance with Paragraphs 2.B and 2.C. of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A1081, dated June 4, 1999:
(1) Perform a DPV pressure check for leakage, and, if necessary, either
(i) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser, or
(ii) Deactivate the thrust reverser in accordance with paragraph 2(B)(8)(a) of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A1081, dated June 4, 1999, provided, however, that within 10 days after deactivation the DPV is replaced with a serviceable assembly and an operational check of the thrust reverser is then performed.
(2) Replace the DPV assembly with a serviceable assembly and then perform an operational check of the thrust reverser.
Serviceable DPV Assembly
(e) For the purpose of this AD, a serviceable DPV assembly is an assembly that has accumulated zero time in service, or an assembly that has accumulated zero time in service after having passed the tests in the Middle River Aircraft Systems Component Maintenance Manual GEK 85007 (78-31-51), Revision No. 6 or later, Directional Pilot Solenoid Valve, Page Block 101, Testing and Troubleshooting, or an assembly that has been successfully leak checked in accordance with Paragraph 2.B. of the Accomplishment Instructions of Middle River Aircraft Systems ASB No. 78A4022 or ASB No. 78A1081, both dated June 4, 1999, as applicable, immediately prior to installation on the airplane.
Airplane Flight Manual (AFM) Changes
(f) If one or both thrust reversers are deactivated, then prior to further flight, revise the Limitations Section of the FAA-approved AFM to include the following:
"The takeoff performance on wet and contaminated runways with a thrust reverser(s) deactivated shall be determined in accordance with Airbus Flight Operations Telex (FOT) 999.0066/99, dated June 9, 1999, as follows:
For takeoff on wet runways, use performance data in accordance with paragraph 4.1.1 of the FOT.
For takeoff on contaminated runways, use performance data in accordance with paragraph 4.1.2 of the FOT."
(1) Notwithstanding the provisions of the FAA approved A300-600 and A310 Master Minimum Equipment List (MMEL), dispatch with both thrust reversers deactivated, for the purposes of complying with this AD, is approved.
(2) Notwithstanding the provisions of the FAA Approved A300-600 and A310 MMEL, airplanes which have deactivated one or both thrust reversers in compliance with this AD, may not conduct operation on contaminated runways, as defined in Airbus Flight Crew Operating Manual Section 2.18.50, unless all components of the Main Wheel Brakes, Green and Yellow Brake Systems, Antiskid System, Ground Spoiler System, and all Spoiler and Speed Brake Surfaces, operate normally.
NOTE 2: The "FCOM" referenced in Airbus FOT 999.0066/99, dated June 9, 1999, is Airbus Industrie Flight Crew Operating Manual (FCOM), Revision 27 for Airbus Model A310 series airplanes and Revision 22 for A300-600 series airplanes. [The revision number is indicated on the List of Effective Pages (LEP) of the FCOM.]
(g) Prior to further flight, revise the Emergency Procedures Section of the FAA-approved AFM for Airbus Model A310 and A300-600 airplanes to include the following statement. This may be accomplished by inserting a copy of this AD into the AFM. In the event of any indication of an in-flight thrust reverser deployment or a "ENG REV UNLK" ECAM caution message triggered in flight, this procedure must be applied.
"Indicated In-flight Thrust Reverser Deployment Procedure:
1. THROTTLE (Affected Engine)........... IDLE
IF BUFFET OR BANK
2. FUEL LEVER (Affected Engine).........OFF
3. MAX SPEED............................. 240 KIAS
NOTE: Item 1 of the procedure, and if buffet or bank is detected, items 2 and 3, should be accomplished immediately from memory.
NOTE: Use recommended single engine landing configuration and 1.3Vs approach speed plus 10kt.
IF NO BUFFET OR BANK
4. THROTTLE (Affected Engine)........... KEEP AT IDLE
5. MAX SPEED............................. 300 KIAS
The "Indicated In-flight Thrust Reverser Deployment Procedure" listed above supersedes the "ENG REV UNLK" procedure of the "Procedures Following Failure" Section of the FAA approved AFM, section number 4.02.00, page 1."
NOTE 3: Notwithstanding procedures in the Procedures Following Failure Section of the FAA approved AFM, displayed on the on-board ECAM computer screen, published in the Airbus FCOM, or QRH, or contained in FAA approved company checklists and/or procedures, flightcrews operating A300-600 or A310 airplanes with one of more thrust reverser activated, must follow the procedure of paragraph (g) in the event of any indication of an in-flight thrust reverser deployment triggered in flight.
NOTE 4: An in-flight thrust reverser deployment may be indicated by master caution aural and visual warnings, and/or a REV UNLK light, and/or an "ENG REV UNLK" ECAM caution message, and/or airplane buffet or bank.
(h) 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, Engine Certification Office (ECO). Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, ECO.
NOTE 5: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the ECO.
(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. Incorporation by Reference
(j) The actions required by this AD shall be done in accordance with the following service documents:

Document No.
Pages
Date
Middle River Aircraft
Systems CF6-80A1/A3
ASB 78A4022
1-16
June 4, 1999
Total pages: 16.

Middle River Aircraft
Systems CF6-80C2A
ASB 78A1081
1-15
June 4, 1999
Total pages: 15.

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Middle River Aircraft Systems, Mail Point 46, 103 Chesapeake Park Plaza, Baltimore, MD, 21220-4295, attn: Product Support Engineering; telephone (410) 682-0093, fax (410) 682- 0100; and Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.
(k) This amendment becomes effective on September 24, 1999.

The Federal Aviation Administration (FAA) received a report of inadvertent thrust reverser deployment on a Pratt & Whitney powered Airbus Industrie A300-600 series aircraft. Following that event, the FAA reviewed thrust reverser safety analyses on other make and model engines, including General Electric Company (GE) CF6-80A1/A3 and CF6-80C2A series turbofan engines. A review of thrust reverser actuation system (TRAS) shop findings and component failure rate data, test data, and system safety analyses revealed that a hidden failure mode involving the directional pilot valve (DPV) exists. The DPV controls the direction of the operation of the center drive unit when the TRAS is activated. If high pressure downstream of the pressure regulating and shutoff valve (PRSOV) exists in combination with a leaking DPV, an inadvertent deployment could occur. High pressure downstream of the PRSOV can be caused by auto restow, PRSOV open failures, or significant PRSOV leakage. PRSOV open failures and significant PRSOV leakage are detected by the DPV pressure switch. DPV open failures and significant DPV leakage are detected by the inability to stow the reverser. However, there exists a range of DPV leakage rates from a closed DPV which are not detectable during normal operation. This undetectable failure mode of the DPV, concurrent with high pressure downstream of the PRSOV, can result in an inadvertent thrust reverser deployment. This condition, if not corrected, could result in inadvertent thrust reverser deployment, which, if it occurred in-flight, could result in loss of control of the airplane. Service Information
The FAA has reviewed and approved the technical contents of Middle River Aircraft Systems Alert Service Bulletin (ASB) No. 78A4022, applicable to GE CF6-80A1/A3 series engines, and ASB No. 78A1081, applicable to GE CF6-80C2A series engines, both dated June 4, 1999, that describe procedures for DPV pressure checks for leakageand operational checks of the thrust reverser, and refer to applicable manuals in the necessity of replacing the DPV assembly or deactivating the reverser. Required Actions
Since an unsafe condition has been identified that is likely to exist or develop on other engines of the same type design, this AD is being issued to prevent inadvertent thrust reverser deployment. This AD requires, prior to further flight, one of the following: (1) performing a DPV pressure check for leakage, and, if necessary, replacing the DPV assembly with a serviceable assembly and performing an operational check of the thrust reverser, or deactivating the thrust reverser; or (2) replacing the DPV assembly with a serviceable assembly and performing an operational check of the thrust reverser. Thereafter, this AD requires one of these actions at intervals not to exceed 700 hours time-in-service. The FAA has determined that whereas deactivation of the thrust reverser(s) addresses the unsafe condition of thisAD, the resultant decrease in airplane stopping performance is acceptable only on a time-limited basis. For this reason, deactivation of the thrust reverser(s) is only allowed after a DPV pressure check has been performed and established the need for the DPV to be replaced with a serviceable DPV and none is available. The FAA has determined that the necessary replacement of the DPV shall be accomplished not later than 10 calendar days from the time of deactivation. If a thrust reverser is deactivated, this action requires, prior to further flight, a revision of the FAA-approved airplane flight manual (AFM) for airplanes equipped with these engines to require performance penalties to be applied for certain takeoff conditions. The actions are required to be accomplished in accordance with the service documents described previously. AFM Changes
The FAA has determined that in the event of an in-flight thrust reverser deployment, airplane controllability may not be adequately maintained with the existing "ENG REV UNLK" procedure of the "Procedures Following Failure" Section of the FAA approved AFM. The AD includes an "Indicated In-flight Thrust Reverser Deployment Procedure," with certain steps recalled from memory by the flightcrew, for inclusion in the AFM Emergency Procedures section of the FAA approved AFM. This new procedure supersedes the existing "ENG REV UNLK" procedure. The FAA finds that this new procedure to be used in the event of any indication of an in-flight thrust reverser deployment provides for more expeditious shutdown of a suspected engine and slowing of the airplane if airplane buffet or bank is experienced. The changes to the AFM required by this AD have been coordinated with the FAA Transport Airplane Directorate.
Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days. Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this 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 under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.
Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the 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 AD 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 Number 99-NE-41-AD." The postcard will be date stamped and returned to the commenter.
The regulations adopted herein will 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to theauthority delegated to me by the Administrator, the Federal Aviation Administration amends 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: