47-41-02 BELL: (Was Mandatory Note 14 of AD-1H-2.) Applies to Models 47B and 47B3 Helicopters.
Compliance required prior to next flight after receipts of parts from Bell Aircraft Corp., but, in any event, not later than January 1, 1948.
To prevent excessive vibration and subsequent failure of the main oil line from the oil cooler to the oil filter, two additional supports must be installed for this oil line, one each at the bends near the oil filter and oil cooler.
(Bell Service Bulletin 47C28 (revised), dated July 1, 1947, covers this same subject.)