Service difficulty report · Clamp · Lear 35LEAR

Difficulty date
August 4, 2005
Submitted
September 1, 2005
Operation
General aviation
Make and model
Lear 35LEAR
Aircraft time
17,260 hours
Engine
Garrtt TFE73122B
Part
Clamp
Part number
420C75275M
Condition
Loose
Location
Bypass Valve
Component
Bypass Valve
Component part number
21000142
Stage of operation
CR
How discovered
O
Nature of condition
J
Precautionary procedure
A

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

(CAN) AT 38000 FEET THE LT FUEL COMPUTER WENT OFF LINE. SHORTLY AFTER THE RT COMPUTER WENT OFF LINE. THIS WAS FOLLOWED BY EXCESSIVELY HIGH TEMPERATURE BUILDING IN THE CABIN WITH NO CONTROL OF THE ENVIRONMENTAL SYSTEM. THE CREW DECIDED TO LAND. MAINTENANCE TROUBLESHOOTING REVEALED A CONNECTOR CLAMP FOR THE HOT AIR BYPASS VALVE HAD COME LOOSE. FURTHER INVESTIGATION FOUND 6 OUT OF 8 CLAMPS WERE LOOSE. THE CLAMPS WERE RE-TORQUED AND LEAK CHECKED SERVICEABLE LACK OF LOCK WIRE ON THE CLAMPS POSSIBLY CONTRIBUTED TO THIS OCCURRENCE. ALL CLAMPS WERE RE-CHECKED AND LOCK WIRED WHEN THE AIRCRAFT RETURNED TO BASE.