80-08-07 ROCKWELL INTERNATIONAL: Amendment 39-3750. Model NA265-40 (all), -60 (all) and -70 S/N 370-2 through -6 and 370-8 and -9 series airplanes except those modified by Supplemental Type Certificate SA687NW, certificated in all categories.
Compliance required as indicated, unless already accomplished.
To prevent adverse flight characteristics resulting from elevator delamination accomplish the following:
(a) On aircraft with honeycomb elevator trailing edge surfaces in service for one calendar year or more, or with 1,000 hours' time in service, whichever occurs earlier;
(1) Within 100 hours' additional time in service, or within 30 days from the effective date of this AD, whichever occurs earlier, inspect left and right elevator trailing edges for delamination as specified in paragraphs 1(a) and 1(b) of "Modification Instructions" of Rockwell International Service Bulletin No. 48 dated January 9, 1980, and;
(2) At intervals not to exceed 500 hours' timein service or 6 months from the last such inspection, whichever occurs sooner, repeat the inspection of paragraph (a)(1) of this AD.
(b) Repair delaminated elevator trailing edges prior to further flight per paragraph 3 of "Modification Instructions" of Rockwell International Service Bulletin No. 48 dated January 9, 1980 and prior to the accumulation of 1,000 hours' additional time in service on new trailing edges, inspect per paragraph (a)(1) of this AD and reinspect at repetitive intervals specified per paragraph (a)(2) of this AD.
(c) Installation of non-honeycomb trailing edges constitutes terminating action for the inspections required by this AD.
(d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections required by this AD.
(e) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region.
This amendment becomes effective April 21, 1980.