90-07-10 R1 CESSNA CITATION: Amendment 39-6599. Final copy of, and revision to, priority letter. Docket No. 90-NM-54-AD.
Applicability: Model 550, 551, and S550 series airplanes, equipped with STC SA2698SW Freon Air Conditioners installed in the aft section of the baggage compartment, certificated in any category.
Compliance: Required as indicated, unless already accomplished.
To prevent failure of the elevator or rudder control cables, accomplish the following:
A. Prior to further flight, deactivate the air conditioning system by pulling the air conditioner supply breakers on the main junction box and install tie wraps on the breakers.
B. Within the next 10 hours time-in-service, perform a visual inspection of the elevator control cables under and in the vicinity of the aft baggage compartment floor for evidence of damage caused by electrical arcing and interference.
1. Replace any damaged cable prior to further flight.
2. If fasteners used to secure the compressor condenser unit mounting rails to the baggage floor interfere with the control cables, replace mounting hardware, prior to further flight, in accordance with Keith Service Bulletin No. 108, dated March 26, 1990.
C. Prior to reactivating the air conditioning system, replace mounting hardware on the inboard mounting rail and replace existing ground wire, in accordance with Keith Service Bulletin No. 108, dated March 26, 1990.
D. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Special Programs Office, ASW-190, FAA, Southwest Region.
NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment, and then send it to the Manager, Special Programs Office, ASW-190.
E. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.
All persons affected by this directive who have not already received the appropriate service documents from the manufacturer, may obtain copies upon request to Keith Products, Inc., 4554 Claire Chennault, Dallas, Texas 75248. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the FAA, Southwest Region, Special Programs Office, 4400 Blue Mound Road, Fort Worth, Texas.
Portions of this amendment were effective earlier to all recipients of Priority Letter AD 90-07-10, dated March 29, 1990.
Airworthiness Directive 90-07-10 R1 supersedes Priority Letter AD 90-07-10, issued on March 29, 1990.
Amendment 39-6599, AD 90-07-10 R1 became effective on May 29, 1990.