56-01-01 BELL: Applies to Model 47G, Serial Numbers 666 Through 1411 and Model 47G2, Serial Numbers 1342 Through 1412.
Compliance required as soon as possible, but not later than January 31, 1956.
Ventral fin support angle braces, P/N 47-267-085-5 and -6 shafe the tail boom longeron, P/N 47-267-057-111 due to interference of these parts. The longeron must be inspected on both sides for wear and damage. Any damage of the longeron in excess of 0.008 inch, based on the diameter of the undamaged tube, must be repaired. 1/32 inch clearance must be provided between the support angle braces and the longeron. Additional rework of the 47-267-057-167 angle brace by the welding of a 1/16-inch steel plate, 3/4-inch x 3 inches, to the back of this part may be necessary to provide adequate clearance, if repair of the longeron by means of a split tube sleeve has been accomplished.
(Bell Mandatory Service Bulletin No. 103 dated September 30, 1955, covers this same subject and outlines the details of the inspection and repairs.)