AD 63-25-01

63-25-01 BEECH: Amdt. 652 Part 507 Federal Register December 5, 1963. Applies to Model 35 Aircraft Serial Numbers D-1 through D-1500, Model 35R Aircraft Serial Numbers D- XXR1 and up (35R Aircraft are Remanufactured Model 35 Aircraft and Retain the Original Serial Number in Addition to the Appropriate 35R Serial Number), and Model Super V Conversions of the Standard Beech Models 35, A35, or B35 Serial Numbers SV-XXX-D-1 through SV-XXX-D-1500.

Compliance required within 25 hours' time in service after the effective date of this amendment unless already accomplished within the last 75 hours' time in service and thereafter within 100 hours' time in service from the last inspection.

Inspections required by AD 62-02-01 have not been adequate to detect all fatigue cracks in the steel center section front trusses prior to failure. To preclude these failures, modify the fuselage and inspect the front and rear steel trusses in accordance with (a) and (b).

In order to gain access to the front and rear trusses, remove the front seat bottom, rear seat, front and rear spar forward partitions, and all floorboards adjacent to the front and rear spars. Also, disconnect the air duct on the right side of the forward spar and remove any other adjacent installations as found necessary for access.

(a) Front truss and fuselage.

Modify the fuselage in accordance with (a)(1) prior to inspecting. Inspect in accordance with (a)(2) within the next 25 hours' time in service unless the aircraft has been so inspected within the last 75 hours' time in service and thereafter within 100 hours' time in service and thereafter within 100 hours' time in service from the last inspection.

(1) Cut two 3 1/2 inch diameter inspection openings in the fuselage skin just under the forward centersection steel truss at right and left butt stations 16.50 inches, in accordance with Beech Service Bulletin 35-24, as revised November 5, 1963, or FAA approved equivalent.

(NOTE: In addition to these two openings, any or all of the three inside inspection openings defined in Service Bulletin 35-24 may be incorporated at the owner's option.)

(2) Inspect the front truss for cracks, using the magnetic particle inspection procedures outlined in Beech Service Bulletin 35-24 as revised November 5, 1963, or FAA approved equivalent.

(3) Cracked trusses shall be replaced or repaired in accordance with Beech Service Bulletin 35-24, as revised November 5, 1963, before further flight. After accomplishment of these repairs the inspection specified in paragraph (2) shall be continued.

(b) Rear truss.

Inspect in accordance with either (1) or (2).

(1) Visual inspection. Within 500 hours' time in service since the last visual inspection, performed in accordance with Beech Service Bulletin 35-24 as revised December 1961, and continually thereafter within 500 hours' time in service from the last inspection, conduct a thorough visual inspection for cracks with adequate lighting, a 3-power magnifying glass, and mirror.

(2) Magnetic particle inspection. Within 1,000 hours' time in service since the last magnetic particle inspection performed in accordance with Beech Service Bulletin 35-24 as revised December 1961, and continually thereafter within 1,000 hours' time in service from the last inspection, inspect for cracks using the magnetic particle inspection procedures outlined in Beech Service Bulletin 35-24 as revised November 5, 1963, or FAA approved equivalent.

(3) Cracked trusses shall be replaced or repaired in accordance with Beech Service Bulletin 35-24 as revised November 5, 1963, before further flight. If the truss is repaired, the next inspection shall be within 100 hours' time in service after the repairs were accomplished. (Any cracks that may develop because of the localized heating during repair should be detectable by this time.) Following this inspection, subsequent inspections shall be at500 or 1,000 hours' time in service, in accordance with (1) or (2), depending on whether a visual or a magnetic particle inspection was performed.

(c) If the front truss is replaced with a new heavier steel truss (Beech P/N 35- 410030-17), the requirements specified in (a) shall become applicable 2,000 hours' time in service after installation of this truss.

NOTE: Model 35 airplanes whose steel carry-through trusses have been modified in accordance with an STC that prescribes inspection intervals that differ from those prescribed in this AD, shall be inspected in accordance with the inspection intervals of the STC.

(d) If the front truss is replaced with a new aluminum truss installed in accordance with Beech Kit No. 35-694, the requirements specified in (a) are not applicable.

(e) An appropriate entry in the airplane log shall be made showing whether the front, rear or both truss(es) were inspected and the type of inspection on the rear truss.

This supersedes AD 62-02-01.

This directive effective December 10, 1963.

Revised April 24, 1964.

Revised February 16, 1965.

Revised January 19, 1967.