70-02-08 BRITISH AIRCRAFT CORP.: Amdt. 39-918. Applies to Viscount Models 744, 745D, and 810 series airplanes which have fuselage leading edge frame structure reinforcing plates, P/N 70152-2787/8 or P/N 70152-3311/12 installed.
Compliance is required as indicated unless already accomplished.
To prevent failure of the fuselage leading edge frame structure, accomplish the following:
(a) For airplanes which have reinforcing plates P/N 70152-2787/8 installed, visually inspect the reinforcing plates for cracks within the next 500 landings after the effective date of this AD, unless already accomplished within the last 500 landings, or within 1,000 landings after the reinforcing plates were installed, whichever occurs later, and thereafter at intervals not to exceed 1,000 landings since the last inspection. If cracks are found, comply with paragraph (c) of this AD within the next 500 landings.
(b) For airplanes which have reinforcing plates, P/N 70152-3311/12 installed,visually inspect the reinforcing plates within the next 1,500 landings after the effective date of this AD unless already accomplished within the last 1,500 landings or within 3,000 landings after the reinforcing plates were installed, whichever occurs later, and thereafter at intervals not to exceed 3,000 landings since the last inspection. If cracks are found, comply with paragraph (c) of this AD within the next 500 landings.
(c) If cracks are found during the inspection required by paragraphs (a) and (b) of this AD, replace the cracked reinforcing plates with new plates P/N 70152-3311/12 by the incorporation of Modification D.3072 Part (d) (for Models 744 and 745D series airplanes) or Modification FG.1928 Part (d) (for Model 810 series airplanes), or FAA-approved equivalents.
(d) Upon request by the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Certification Staff, FAA Europe, Africa, and Middle East 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 the operator.
(e) For the purpose of complying with this AD, subject to the acceptance by the assigned FAA maintenance inspector, the number of landing may be determined by dividing each airplane's hours' time in service by the operator's fleet average time from takeoff to landing for the type aircraft.
(British Aircraft Corp., Ltd., Preliminary Technical Leaflets No. 242, Issue 4 (Model 744 and 745D airplanes) and No. 106, Issue 4 (Model 810 series airplanes) cover this subject and present an approved accessibility scheme to facilitate the inspections required by paragraphs (a) an (b)).
This amendment becomes effective February 8, 1970.