69-26-02 HAWKER SIDDELEY AVIATION, LIMITED: Amdt. 39-894. Applies to Heron Model D.H. 114 Airplanes.
Compliance is required as indicated.
To reduce the possibility of fatigue cracks developing in the engine mount pick-up wing straps located at the top outboard position of the left and right inboard engine-to-wing attachment structure, accomplish the following:
(a) Within 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 250 hours' time in service, remove the top cowling panel over the oil tank on the right and left inboard engine installations and visually inspect the upper outboard engine mounting pick-up wing straps for fatigue cracks using a dye penetrant method and in accordance with Hawker Siddeley Technical News Sheet, Series Heron 114, No. W.15, Issue 1, dated 27 October 1969, or an FAA-approved equivalent.
(b) Within the next 300 hours' time in service after accomplishing the inspection required byparagraph (a), accomplish the following:
(1) Remove and discard the two aft bolts and nuts which attach the upper outboard engine mount pick-up straps of the left and right inboard engine installation structure to the engine mounting pick-up fitting.
(2) Accomplish the inspection required in paragraph (a).
(3) Replace the bolts and nuts removed in accordance with subparagraph (1) with new bolts, P/N A.25/4E, and new nuts, P/N A.16Y/ET in accordance with Hawker Siddeley Technical News Sheet, Series Heron (114), No. W.15, Issue 1, dated 27 October 1969, or an FAA-approved equivalent.
(c) Within the next 600 hours' time in service after compliance with paragraph (b) and thereafter at intervals not to exceed 600 hours' time in service since the last inspection, accomplish the inspection required by paragraph (a).
(d) If cracks are found during any of the inspections required by paragraphs (a), (b), and (c) replace the cracked wing strap with a new strap in accordance with Hawker Siddeley Technical News Sheet, Series Heron (114), No. W.15, Issue 1, dated 27 October 1969, or an FAA-approved equivalent.
This amendment becomes effective December 18, 1969.