Airworthiness Directive · Amendment 39-11884 · Lockheed Model L-1011-385 Series Airplanes
Lockheed Model L-1011-385 Series Airplanes
All Model L-1011-385 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 (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.
This amendment adopts a new airworthiness directive (AD), applicable to all Lockheed Model L-1011-385 series airplanes, that requires modifications of the engine turbine cooling air panel at the flight engineer/second officer's console, pilot's caution and warning light panel on the main instrument panel, and monitoring system for the engine turbine air temperature. This amendment is prompted by reports of an undetected fire breaching the high speed gearbox (HSGB) case on certain Rolls Royce engines installed on in-service airplanes due to lack of an internal fire detection system within the HSGB. The actions specified by this AD are intended to prevent undetected fires originating within the HSGB from breaching the HSGB case, which could result in engine damage and increased difficulty in extinguishing a fire.
To prevent undetected fires originating within the high speed gearbox (HSGB) from breaching the HSGB case, which could result in engine damage and increased difficulty in extinguishing a fire, accomplish the following:
(a) Within 24 months after the effective date of this AD, accomplish the actions specified in paragraphs (a)(1), (a)(2), and (a)(3) of this AD, in accordance with Lockheed Service Bulletin 093-77-059, dated February 25, 1998; or Revision 1, dated February 2, 1999.
(1) Modify the engine turbine cooling air panel at the flight engineer/second officer's console.
(2) Modify the pilot's caution and warning light panel on the main instrument panel.
(3) Modify the monitoring system for the engine turbine air temperature.
Note 2: Lockheed Service Bulletin 093-77-059 refers to Rolls Royce Service Bulletins RB.211-72-C178, dated March 20, 1998; and RB.211-77-C144, dated August 7, 1998; as additional sources of service information for accomplishment of the modification of the monitoring system for the engine turbine air temperature.
(b) As of the effective date of this AD, no person shall install on any airplane, an engine turbine cooling air panel assembly, part number 1559672, or a pilot's caution and warning light panel assembly on the main instrument panel, unless it has been modified in accordance with paragraphs (a)(1) and (a)(2) of this AD, as applicable.
