62-16-03 LOCKHEED: Amdt. 461 Part 507 Federal Register July 12, 1962. Applies to All Models 1049-54, 1049B, 1049C, 1049D, 1049E, 1049F, 1049G, and 1049H Series Aircraft.
Compliance required as indicated.
As a result of corrosion found on the wing rear spar upper cap exposed surfaces which exceeded the negligible damage limits the following is required:
(a) Within the next 700 hours' time in service after the effective date of this AD, unless already accomplished, inspect the exposed surfaces of the rear spar upper caps from wing Station 80 to wing Station 458 using a wood or micarta pick as a probe and a good light source to illuminate the area.
(b) If no corrosion is found, coat the spar cap with zinc chromate primer. The aircraft may then be returned to service.
(c) If corrosion damage is found on the exposed surfaces of the rear spar upper cap, remove enough rivets from the aft upper surface skin to allow lifting the skin for the purpose of inspecting the aftouter surface of the rear spar upper cap in accordance with (a).
(d) Repair all corrosion damage in accordance with Lockheed Report 8882, figure 2- 25 and paragraph 1-67N, or FAA approved equivalent. If no corrosion is found on the aft outer surface of the rear spar upper cap, coat it with zinc chromate.
(e) All rear spar upper caps which have been inspected and repaired in accordance with (a) through (d) shall be reinspected and repaired in accordance with (a) through (d) at periods thereafter not to exceed 5,000 hours' time in service or two calendar years, whichever occurs first. The first periodic reinspection of any rear spar upper cap which was inspected and repaired in the manner prescribed in (a) through (d) prior to the effective date of this AD, shall be accomplished within 5,000 hours' time in service or two calendar years, whichever occurs first, following the date of that inspection.
(f) Upon request of the operator, and FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator.
(Lockheed Field Service Letters FS/249582L dated November 4, 1960, and FS/250141L dated December 20, 1960, cover this same subject.)
This directive effective August 13, 1962.