71-09-01 CESSNA: Amdt. 39-1193. Applies to all Model 320 series Airplanes.
Compliance: Required as indicated, unless already accomplished.
To prevent nacelle electrical failures and inflight electrical fires, accomplish the following:
A) Within the next 50 hours' time in service after the effective date of this AD, and thereafter at intervals not to exceed 100 hours' time in service from the date of the last inspection, visually inspect the following:
1) The insulating material of the electrical wiring, grommet and clamps located in the engine nacelles between the canted bulkhead and the firewall for charred, burnt or heat hardened conditions;
2) The heat shields located in the engine nacelles between the canted bulkhead and the forewall for deterioration or improper installation and attachment that could contribute to excessive heat in this area.
B) If any of the conditions described in Paragraph A are found during the required inspections, prior tofurther flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the replacement can be performed, replace any defective parts with airworthy parts. The replacement of defective parts does not relieve the requirement for the repeated inspections specified in Paragraph A.
C) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA, Central Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator.
D) On or before January 1, 1972 modify the engine nacelles in accordance with Cessna Service Letter ME71-6, dated April 9, 1971, and Cessna Service Kit SK320-53, dated March 5, 1971, or any other method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.
E) When the engine nacelles are modified in accordance with Cessna Service Letter ME71-6, dated April 9, 1971, and Cessna Service Kit SK320-53, dated March 5, 1971, the inspections required by Paragraph A will no longer be required.
This amendment becomes effective April 23, 1971.