67-17-03 FAIRCHILD-HILLER: Amdt. 39-412 Part 39 Federal Register May 16, 1967. Applies to Model F-27 Airplanes, Serial Numbers 1 through 122, and Model FH-227 Airplanes, Serial Numbers 501 through 529.
Compliance required as indicated.
To detect cracks in the skin of the upper inboard forward part of the horizontal stabilizer, accomplish the following:
(a) Within the next 50 hours' time in service after the effective date of this AD, unless already accomplished within the last 100 hours' time in service, and thereafter at intervals not to exceed 150 hours' time in service from the last inspection, remove the stabilizer inboard leading edge fairing and inspect the top skin for cracks in the area from Stabilizer Station 0 to Station 30.0 and aft from the front spar to stringer No. 10, using X-ray, or visually with a glass of at least 10-power, or an FAA-approved equivalent inspection.
(b) If a crack is found during an inspection, repair the crack before further flight with an FAA-approved repair, or replace the cracked part with a part of the same part number that has been inspected in accordance with (a) and found free of cracks, or with an FAA-approved equivalent part.
(c) The repetitive inspection interval specified in (a) may be increased from 150 hours' time in service to 1,200 hours' time in service from the last inspection on Model F-27 Series airplanes modified in accordance with Fairchild Hiller Service Bulletin 55-11, Revision 1, dated November 17, 1966, or later FAA-approved revision, or an FAA-approved equivalent modification, and on Model FH-227 airplanes modified in accordance with Fairchild Hiller Service Bulletin 55-1, Revision 1, dated November 17, 1966, or later FAA-approved revision, or an FAA-approved equivalent modification.
(d) Equivalent inspections and repairs may be approved by an FAA maintenance inspector. Equivalent parts, Service Bulletin revisions, and modifications, must be approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.
(e) Upon request with substantiating data submitted through an FAA maintenance inspector, compliance times specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.
This supersedes AD 66-08-03.
This directive effective May 16, 1967.