68-16-04 GENERAL DYNAMICS: Amendment 39-638. AD 68-16-04 is revised as indicated. Applies to General Dynamics Model 240 airplanes equipped with Rolls Royce MK 542-4 engines and Dowty Rotol (c)R245/4-40-4.5/13 propellers in accordance with General Dynamics Supplemental Type Certificate SA1054WE (hereinafter referred to as the CV-600) and General Dynamics Model 340 and 440 airplanes equipped with Rolls Royce MK 542-4 engines and Dowty Rotol (c) R245-4-40-4.5/13 or Dowty Rotol (c)R259/4-40-4.5/17 propellers in accordance with General Dynamics Supplemental Type Certificate SA1096WE (hereinafter referred to as the CV-640).
Compliance required as indicated unless already accomplished.
To eliminate potential flammable fluid ignition sources in the main landing gear wheel well accomplish the following unless already accomplished:
(A) Inspection requirements, CV-600 and CV-640
(1) Compliance required within the next 50 hours' time in service after the effective date of this Airworthiness Directive unless already accomplished within the last 135 hours' time in service and thereafter not to exceed 185 hours' time in service.
(a) Inspect the mating surfaces of the engine exhaust duct flange joint thermal insulation collar, P/N's 2D6220119-31, -41, and -43 with the engine exhaust duct thermal insulation blanket assemblies for possible gaps. For purposes of this inspection, the engine exhaust system component temperatures shall be no greater than the outside ambient air temperature.
(b) If gaps are found, the thermal insulation collar and/or adjacent thermal insulation blanket must be replaced with new or overhauled insulation collars and/or blankets.
(2) Compliance required within the next 125 hours' time in service after the effective date of this Airworthiness Directive unless already accomplished within the last 125 hours' time in service and thereafter not to exceed 250 hours' time in service.
(a) Inspect the engine exhaust duct flange joints for leakage by inspection of the gaskets and the internal surface of the thermal insulation collars, Part Numbers 2D6220119-31, -41, and -43, or by an equivalent method approved by the Chief, Aircraft Engineering Division, FAA Western Region.
(b) If exhaust leakage is found, replace exhaust duct flange joint gaskets with two gaskets, General Dynamics/Convair P/N 2D6220115-15, at the forward flange and two gaskets, General Dynamics/Convair P/N 2D6220127-9, at the aft flange or equivalent replacements approved by the Chief, Aircraft Engineering Division, FAA, Western Region.
(3) Upon request of the operator, FAA Maintenance Inspectors, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western Region, may adjust the repetitive inspection intervals specified in this Airworthiness Directive to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator.
(4) Upon completion of the work described in (B)(1)(a), below, the inspection requirement of (A) is no longer applicable.
(B) Modification and Relocation Requirements, CV-600 and CV-640
(1) Within the next 4,000 hours' time in service after the effective date of this Airworthiness Directive unless already accomplished.
(a) Modify the engine exhaust duct flange joint thermal insulation collars, P/N's 2D6220119-31, -41 and -43 in accordance with General Dynamics Service Bulletin 600(240D) 640(340D) S.B. No. 78-3 or later FAA approved revision or an equivalent method approved by the Chief, Aircraft Engineering Division, FAA Western Region.
(b) Modify the electrical insulation in the alternating current generator control unit (P/N 914F597) in accordance with Westinghouse Aerospace Service Bulletins 67-802 and 67-803 or later FAA approved revisions or an equivalent method approved by the Chief, Aircraft Engineering Division, FAA Western Region.(c) Relocate the alternating current generator control unit (P/N 914F597) as follows:
(i) For CV-600 aircraft, per General Dynamics Service Bulletin 600(240D) S.B. No. 24-1 or an equivalent method approved by the Chief, Aircraft Engineering Division, FAA Western Region; and
(ii) For CV-640 aircraft per General Dynamics Service Bulletin 640(340D) S.B. No. 24-2 or later FAA approved revision or an equivalent method approved by the Chief, Aircraft Engineering Division, FAA Western Region.
This amendment becomes effective on December 27, 1968.