AD 79-13-08

79-13-08 AIRBORNE MANUFACTURING COMPANY: Amendment 39-3507. Applies to the below listed part number Dry Air Pumps installed on piston engine aircraft certificated in all categories.

AIRBORNE PART NUMBER

SERIAL NUMBERS 211 CC 5E9318 thru 5E9347

5E9407 thru 5E11419 211 CC-9 5E616 thru 5E715 211 CC TR 5E1264 thru 5E1406 212 CW 5E3403 thru 5E4197

5E9129E thru 5E9131E 212 CW-6 5E9 thru 5E25 242 CW-4 5E8 thru 5E11 441 CC 5E332 thru 5E401

5E450 thru 5E483 441 CC-7 5E911 thru 5E981 441 CC-9 5E75 thru 5E80 441 CC-11 5E4 441 CC-13 5E7 thru 5E12 441 CC-17 5E106 thru 5E116 442 CW 5E926 thru 5E1023 442 CW-4 5E137 thru 5E149 442 CW-6 5E765 thru 5E785 442 CW-8 5E114 442 CW-12 5E431 thru 5E435

These pumps were not available for installation before May 15, 1979, therefore, dry air pumps installed previous to that date are exempt from this AD. Compliance is required prior to next flight.

To prevent catastrophic failure of the pump and subsequent loss of the vacuum system remove above listed dry air pumps from service and replace with an airworthy pump of the same part number. An airworthy pump is one which has a serial number not listed above or if listed above also has an "A" or "2" ink stamped by the manufacturer with black ink on the periphery of the body near the mounting flange. The aircraft may be flown under day VFR conditions in accordance with FAR 21.197 to a base where the corrective action can be performed. Additional information concerning disposition of the affected pumps is contained in Airborne Manufacturing Company, Aviation Products Group, Service Letter Number 22A, dated June 5, 1979.

This amendment becomes effective upon publication in the Federal Register, as to all persons except those to whom it was made immediately effective by the airmail letter dated June 7, 1979, which contained this amendment.