52-05-03 BELL: Applies to All Model 47 Helicopters Incorporating Engine Mount Assembly, P/N 47-612-11-1 or -5.
Compliance recommended upon receipt of parts, but required not later than the next 25- hour inspection following receipt of parts or April 1, 1952, whichever occurs first.
As a precautionary measure against the serious consequences resulting from the failure of this particular engine mount, Safety Strap Kit, P/N 47-612-132, must be installed. This kit can be obtained free of charge from the Bell Aircraft Corp., and must be installed in accordance with Bell Service Bulletin No. 87.
AD 51-27-01 remains in effect and is used in conjunction with this directive.
(Bell Service Bulletin No. 87 dated February 12, 1952, covers this same subject.)