AD 85-16-01

85-16-01 BOEING: Amendment 39-5114. Applies to Boeing Model 767 series airplanes certificated in any category. Compliance is required as indicated, unless already accomplished.

To preclude failure of the Pneumatic System Pressure Regulating and Shutoff Valve (PRSOV), and to assure its integrity when commanded closed by a crew procedure, accomplish either paragraph A. or B., below, (1) within the next 200 hours time-in-service on the PRSOV, or prior to the accumulation of 1500 hours time-in-service on the PRSOV, whichever occurs later, on airplanes equipped with General Electric CF6-80 series engines, or (2) within the next 500 hours time-in-service on the PRSOV, or prior to accumulation of 3000 hours time-in-service on the PRSOV, whichever occurs later, on airplanes equipped with Pratt & Whitney JT9D series engines:

A. Replace the PRSOV, Hamilton Standard P/N 773288, with a serviceable valve. Repeat this procedure for replacement valves not modified in accordance with paragraph B. below, (1) prior to the accumulation of 1500 hours time-in-service on the valve, on airplanes equipped with General Electric CF6-80 series engines, or (2) prior to the accumulation of 3000 hours time-in-service on the valve, on airplanes equipped with Pratt & Whitney JT9D series engines.

B. Accomplish PRSOV modification in accordance with Hamilton Standard Service Bulletin 36-2030, dated March 8, 1985, or later FAA-approved revisions. Valves modified in accordance with this bulletin are not subject to a repetitive replacement, and constitute terminating action for this AD.

NOTE: In the event an operator is unable to establish the accumulated hours time-in- service on a given PRSOV installed on an airplane, the total hours accumulated on the airplane must be used in the determination of replacement or modification times for the PRSOV.

C. Alternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, SeattleAircraft Certification Office, FAA, Northwest Mountain Region.

D. 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 and/or modifications required by this AD.

All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124, or to Hamilton Standard, Bradley Field Road, Windsor Locks, Connecticut 06096. These documents also may be examined at FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective August 19, 1985.