Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
SW-07-33
May 2, 2007
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin (SAIB) alerts you,
owners and operators of Bell Helicopter Textron Inc.-manufactured UH-1H
surplus military helicopters, of failures of the quick connect fittings.
Background
There have been reports of failures of the quick connect system
involving the engine and transmission quick connect flexible hose
lines. It is believed that the quick connect fittings, which have no
life limit, may become worn over time due to vibration and fatigue and
allow either an internal mechanism failure or inadvertent
disconnection. The consequence of an inadvertent engine oil line
coupling disengagement is a sudden high oil temperature and pressure
indication followed by possible damage or failure of the engine
bearings. If a transmission oil line quick connect becomes disengaged,
complete loss of transmission oil pressure would occur. This could lead
to damage and possible failure of the transmission.
Recommendations
During scheduled maintenance, we strongly recommend inspecting the
engine and transmission quick connect fittings for functionality per
the referenced maintenance manual and correcting any noncompliance.
These inspections allow measuring wear on the breakaway pins of the
quick connect couplings to determine if the coupling is serviceable.
Reference
Army Technical Manual TM-55-1520-210-23-1, Chapter 4, Section V,
pages 4-46 (Change 42) and Chapter 6, Section III, page 6-72 (Change 19)