AD 73-13-10 R2 ACTIVE

73-13-10 R2 HAWKER SIDDELEY AVIATION, LTD: Amendment 39-1676 as amended by Amendment 39-3133 is further amended by Amendment 39-3797. Applies to all Model DH-125 and BH-125 airplanes.

Compliance is required as indicated.

To prevent possible in-flight failures of the outer flap hinge assembly fittings, accomplish the following:

(a) On airplanes, S/N's 25014, 25074, 25104, 256002, and 256004, before further flight, unless already accomplished within the last 3 months, except that the airplane may be flown in accordance with FAR Section 21.197 to a base where the work can be performed.

(1) Remove the flap outer hinge assembly, including the fittings, P/N's 25WF89A and either 25WF87-8A or 25WF187-8A, and extract the pivot bolt, P/N 25WF91, or the pivot pin, P/N 25WF/Z47/1, as applicable;

(2) Inspect the pivot bolt or pivot pin, as applicable, for cracks, using dye penetrant or an FAA-approved equivalent process; and

(3) If cracks are found during an inspection performed in accordance with paragraph (a)(2), before further flight, as applicable:

(i) Replace cracked pivot bolts, P/N 25WF91, with new parts of the same part number, or with pivot pins, P/N 24WF/Z47/1, of HSA Modification No. 25/2300, Part B, or an FAA-approved equivalent, and thereafter comply with paragraph (e)(5).

(ii) Replace cracked pivot pins with new parts of the same part number or an FAA-approved equivalent, and thereafter comply with paragraph (e)(5).

NOTE: When inspecting a bolt, particular attention should be paid to the bolt shoulder, adjacent to the threaded end.

(b) On airplanes, S/N's 25014, 25074, 25104, 256002, and 256004, before further flight, unless already accomplished within the last 3 months, except that the airplane may be flown in accordance with FAR Section 21.197 to a base where the work can be performed, and thereafter at intervals not to exceed 3 months from the last inspection

(1) Remove all dirt, grease, paint, and other substances from the external surface of the lugs on the outer flap hinge assembly fittings, P/N's 25WF89A and either 25WF87- 8A or 25WF187-8A.

(2) Using a magnifying glass of not less than 10X, inspect the external surface of the lugs on the fittings for cracks; and

xcept that a cracked fitting may be retained in service provided the requirements of paragraph (c) are met, replace the cracked part with a serviceable part of the same part number or an FAA- approved equivalent.

NOTE: During inspection, particular attention should be paid to the crown of the lugs.

(c) A cracked fitting may be retained in service, if - 25WF187-8A -

(i) The fitting is one of a pair incorporating fail-safe links of HSA Modification No. 25/2300, Part A, or an FAA-approved equivalent;

(ii) The mating lugs of the fittings are not cracked;

(iii) The forward lug of the fitting is not cracked; and

(iv) Any cracks in the aft lug of the fitting are in a single plane, parallelto the plane of the fitting.

(2) For upper fittings, P/N 25WF89A, that are installed as one of a pair incorporating fail-safe links of HSA Modification No. 25/2300, Part A, or an FAA-approved equivalent -

(i) The mating lugs of the fitting are not cracked;

(ii) No more than one lug of the forward pair of lugs and no more than one lug of the aft pair of lugs is cracked; and

(iii) Any cracks in a forward or aft lug of the fitting are in a single plane, parallel to the plane of the fitting.

(3) For upper fittings, P/N 25WF89A, that are not installed as one of a pair incorporating fail-safe links -

(i) The mating lugs of the fitting are not cracked;

(ii) No more than one lug of the forward pair of lugs of the fitting is cracked; and

(iii) Any cracks in a forward lug of the fitting are in a single plane, parallel to the plane of the fitting.

(d) On all Hawker Siddeley Model DH-125 and BH-125 airplanes, other than those five airplanes coveredby paragraph (b), within the next 6 weeks after the effective date of this AD, unless already accomplished within the last 6 weeks, and thereafter at intervals not to exceed 3 months from the last inspection, comply with paragraphs (b)(1), (2), and (3).

(e) Replace pivot bolts, P/N's 25WF91, and pivot pins, P/N's 25WF/Z47/1 in accordance with the following:

(1) For pivot bolts which are in place on airplanes, S/N's 25014, 25074, 25104, 256002, and 256004, on the effective date of this AD and are subsequently found to be uncracked at the initial inspection required by this AD, and refitted, before the accumulation of 200 flights or within 3 months after refitting, whichever occurs sooner.

(2) For pivot bolts on Hawker Siddeley Model DH-125 and BH-125 airplanes, other than those five airplanes covered by paragraph (e)(1) which were found to be uncracked at the initial inspection voluntarily conducted in accordance with the applicable HSA Service Bulletins, and refitted, before the accumulation of 200 flights or within 3 months after refitting, whichever occurs sooner.

(3) For new pivot bolts fitted as replacements for uncracked pivot bolts, before the accumulation of 500 flights after such replacement.

(4) For new pivot pins fitted as replacements for uncracked pivot bolts or pivot pins, before the accumulation of 1,200 flights after such replacement.

(5) For new pivot bolts or pivot pins fitted as replacements for cracked pivot bolts or pivot pins, before the accumulation of 200 flights or within 3 months after such replacement, whichever occurs sooner, except that such service life limit may be extended to 1,200 flights, without time limit, if fail-safe links of HSA Modification No. 25/2300, Part A, are installed, or if prior to the accumulation of 200 flights or within 3 months after such replacement, whichever occurs sooner, the fail-safe links of HSA Modification No. 25/2300, Part A are incorporated.

(f) Paragraphs (b), (c), and(d) of this AD do not apply to airplanes required to comply with AD 80-12-10.

Amendment 39-1676 became effective June 27, 1973.

Amendment 39-3133 was effective February 16, 1978, as to all persons except those persons to whom it was made immediately effective by the telegram dated December 1, 1977, which contained this amendment.

This Amendment 39-3797 becomes effective June 23, 1980.