AD 87-03-03

87-03-03 BRITISH AEROSPACE: Amendment 39-5504. Applies to Model 3101 Jetstream (S/N 642 to 646, 648 to 655, 657, 658 and 660 to 666 inclusive) airplanes certificated in any category.

Compliance: Required within 600 hours time-in-service (TIS) after the effective date of this AD, unless already accomplished.

To ensure operation of fuel/hydraulic and water methanol system valves during critical flight operations, accomplish the following:

(a) Modify the HiTemp Valves Part Number (P/N) HTE 4925-001 as follows:

(1) Gain access to the valves in accordance with Section 2. "ACCOMPLISHMENT INSTRUCTIONS", paragraph A PREPARATION", in British Aerospace (BAe) S/B 28-JA850911 dated June 13, 1986.

(2) Replace valve spindles P/N 4925-005 with strengthened spindles P/N 4925-013 in HiTemp Model HTE 1" Actuated Ball Valves in accordance with Section 2. "ACCOMPLISHMENT INSTRUCTIONS" in HiTemp SB HTE 4925/1-SB-1 dated August 19, 1985, on those valves located as follows:(i) Fuel system - left and right LP cocks at wing leading edges outboard of the engines, and crossfeed cock on fuselage center section.

(ii) Hydraulic System - left and right LP cocks in the hydraulic installations below fuselage center section.

(iii) Water Methanol System (if fitted) - stop valves in the left and right main landing gear bays.

(3) Carry out functional tests of the valves in accordance with Section 2. "ACCOMPLISHMENT INSTRUCTIONS", paragraph B "ACCOMPLISHMENT", in BAe S/B 28-JA850911 dated June 13, 1986.

(b) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished.

(c) An equivalent means of compliance with this AD may be used if approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, B-1000, Brussels, Belgium.

All persons affected by this directive may obtain a copy of the document referredto herein upon request to British Aerospace plc, Manager, Product Support Civil Aircraft Division, Prestwick Airport, Ayrshire, KA9 2RW, Scotland; or British Aerospace, Inc., Librarian, Box 17414, Dulles International Airport, Washington, D.C. 20041; or FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106.

This amendment becomes effective on February 17, 1987.