67-33-03 GENERAL DYNAMICS: Amdt. 39-528 Part 39 Federal Register December 29, 1967, as amended by Amendment 39-1528. Applies to Model 240/340/440 airplanes using turbo-propeller power which have been modified to incorporate underwing pressure fueling per STC Nos. SA1316WE, SA1132WE, SA1096WE or SA1054WE.
Compliance required as indicated.
Because of three reports of overpressurization of the wing fuel tank in affected airplane types that have been attributed to failure of the upper and lower diaphragm assemblies in the pressure fueling valves (P/N 2640644 or P/N 2650198), accomplish the following:
(1) Before further flight from the next maintenance base where facilities and personnel are available, externally inspect each wing in the area of the fuel tank for fuel leakage;
(2) If fuel leakage is found as a result of the inspection per Paragraph (1), before further flight internally inspect each wing fuel tank exhibiting fuel leakage for presence of structural damage;
(3) If structural damage is found as a result of the inspection per Paragraph (2), before further flight repair portion of each wing exhibiting structural damage as necessary; and
(4) Within thirty days after the effective date of this amendment to AD 67-33-03, unless already accomplished, install adjacent to each underwing refuel valve in clear view of ground fueling crews a placard stating, 'Remove the overwing filler cap(s) while fueling the tank above 80% capacity. If not, further inspection required per AD 67-33-03.'
When fueling at or above 80% of the fuel tank capacity, perform all underwing fueling with overwing fuel tank filler cap(s) removed. The placard may be removed, and the procedure described in this paragraph may be discontinued after the accomplishment of (5) below.
(5) Compliance with paragraph (4) is no longer required:
(a) When underwing pressure fueling system as installed on the Model 240 aircraft is modified to incorporate a pressure vent valve in accordance with Aircraft Tank Service, Incorporated, Drawing 2036, Change "A", entitled 'Refueling Valve Installation-CV 240', dated April 23, 1966, or later FAA-approved revisions, or an equivalent modification approved by the Chief, Aircraft Engineering Division, Western Region.
(b) When the underwing pressure fueling system as installed on the Model 340/440 aircraft is modified to incorporate a pressure vent valve in accordance with Aircraft Tank Service, Incorporated, Drawing 2363, Change "B", entitled 'Installation of Pressure Vent Valve-Wing Fuel Tanks - Convair 340/440', dated July 3, 1968, or later FAA-approved revisions, or an equivalent modification approved by the Chief, Aircraft Engineering Division, Western Region.
(6) If either (a) fuel leakage or overpressurization is detected in operation, or (b), the aircraft is known to have been refueled not in accordance with the procedure set forth in paragraph (4) above, repeat the inspection described in paragraphs (1) and (2) above, and accomplish repairs, per (3) above, if applicable.
Amendment 39-528 was effective December 29, 1967, for all persons except those to whom it was made effective immediately by telegram issued previously.
This Amendment 39-1528 is effective October 3, 1972.