82-19-02 GENERAL DYNAMICS: Amendment 39-4458. Applies to Model 340, 440, and military models eligible or to be made eligible for civil use under Type Certificate 6A6, and all such model airplanes converted to turbopropeller power, certificated in all categories. Compliance required as indicated unless previously accomplished.
To prevent possible loss of a horizontal stabilizer due to failure of the stabilizer attachment fittings (P/Ns 340-8510150 and 340-8510151) caused by fatigue cracks, accomplish the following:
A. Within 250 hours time in service or within 90 days from the effective date of this AD, whichever occurs first, unless previously accomplished within the last 450 hours of time in service, conduct a visual inspection of the upper and lower, forward and aft, horizontal stabilizer attachment fitting lugs in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions," General Dynamics Convair Division Service Bulletin 640 (340D)55-3A, Revision 1, dated June 12, 1981. If cracks are found, replace with a new part before further flight.
B. Within 250 hours time in service or within 90 days from the effective date of this AD, whichever occurs first, unless previously accomplished within the last 1150 hours of time in service, conduct an ultrasonic inspection of the upper and lower, forward and aft, horizontal stabilizer attachment fitting lugs in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions" of SB 640 (340D) 55-3A. If cracks are found, replace with a new part before further flight.
C. Repeat the visual inspection required by paragraph A of this AD at intervals not to exceed 700 hours time in service from the last such inspection and repeat the ultrasonic inspection required by paragraph B of this AD at intervals not to exceed 1400 hours time in service from the last such inspection.
D. Within 10,000 hours time in service from the effective dateof this AD, unless already accomplished, install bushings in the horizontal stabilizer attachment fitting lug holes in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions" of SB 640 (340D) 55-3A. Continue to visually inspect at 700 hour intervals per paragraph A and to inspect by ultrasonic procedures at 1400 hour intervals per paragraph B of this AD.
E. Within 250 hours time in service or within 90 days from the effective date of this AD, whichever occurs first, unless previously accomplished within the last 450 hours time in service, conduct an internal visual inspection for cracks in the horizontal stabilizer attachment fittings, upper, lower, forward and aft, and associated structure outboard of the lugs and butt rib in the area surrounding the fasteners, in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions" of General Dynamics Convair Division Service Bulletin 640 (340D) 55-4, Revision 1, dated March 24, 1982. Inspect for evidence of loose rivets or fasteners in the stabilizer attachment fittings with particular attention given to those just outboard of the butt rib which fasten the upper forward fittings to the spar web and rail. If cracks are found in the stabilizer attachment fittings or associated structure, and/or if loose fasteners are detected in the stabilizer attachment fitting: replace fitting with a new part, repair structure, and/or replace the fasteners, in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions" of SB 640 (340D) 55-4 before further flight.
F. Within 250 hours time in service or within 90 days from the effective date of this AD, whichever occurs first, unless previously accomplished within the last 1150 hours time in service, conduct an x-ray inspection for cracks in the upper forward and upper aft horizontal stabilizer attachment fittings in the area outboard of the lugs in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions" of SB 640 (340D) 55-4. Only the four (4) upper fittings are required to be x-ray inspected as they are the most highly loaded in tension and therefore most susceptible to fatigue cracking. If cracks are found, replace with a new part before further flight.
G. Repeat the visual inspection required by paragraph E of this AD at intervals not to exceed 700 hours time in service from the last such inspection and repeat the x-ray inspection required by paragraph F of this AD at intervals not to exceed 1400 hours time in service from the last such inspection.
H. Within 10,000 hours time in service from the effective date of this AD, unless already accomplished, replace the first three (3) steel rivets outboard of the butt rib through the two (2) forward upper horizontal stabilizer attachment fittings in accordance with the applicable provisions of paragraph 2 entitled, "Accomplishment Instructions" of SB 640 (340D) 55-4. Continue to visually inspect at 700 hour intervals per paragraph E and x-ray inspect at 1400 hour intervals per paragraph F of this AD.
I. Prior to issuance of a Certificate of Airworthiness for military aircraft being converted for civil certification, and prior to further flight for any aircraft that has been out of service for one (1) year or more, the airplane must be inspected in accordance with paragraphs A, B, E, and F of this AD.
J. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections or modifications required by this AD.
K. Alternative inspections, modifications, or other actions which provide an equivalent level of safety may be used when approved by the Chief, Western Aircraft Certification Field Office, FAA Northwest Mountain Region, Hawthorne, California.
The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1).
All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to General Dynamics, Convair Division, P.O. Box 80877, San Diego, California 92138. These documents also may be examined at FAA Northwest Mountain Region, 17900 Pacific Highway South, C-68966, Seattle, Washington 98168; or Western Aircraft Certification Field Office, 15000 Aviation Boulevard, Hawthorne, California.
This supersedes AD 81-16-07, Amendment 39-4180 (46 FR 39431), issued July 24, 1981, and AD 80-11-01, Amendment 39-3775 (45 FR 35309), issued May 13, 1980.
This Amendment becomes effective September 16, 1982.