Service difficulty report · Generator · Lear 35LEAR

Difficulty date
April 13, 2018
Submitted
April 18, 2018
Operation
Air carrier
Aircraft
N542LM
Make and model
Lear 35LEAR
Aircraft serial
35280
Aircraft time
14,549 hours, 13,070 cycles
Part
Generator
Part number
66082019
Part serial
193
Condition
Failed
Location
Right
Stage of operation
CR
How discovered
O
Nature of condition
H, J
Precautionary procedure
B

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

What was found

AFTER LEVELING OFF AT CRUISE ALTITUDE AFTER ABOUT 5-10 MINUTES THE RT GENERATOR CAUTION LIGHT ILLUMINATED. PILOT NOTED THAT THEY HAD LOST THE RT GENERATOR. RT GENERATOR WOULD NOT RESET AFTER RUNNING THE CHECKLIST. THE LT GENERATOR WAS THEN NOTED TO BE OFFLINE AS WELL. THE FIRST TWO ATTEMPTS TO RESET THE LT GENERATOR DID NOT WORK. THE CREW DECLARED AN EMERGENCY AND STARTED DESCENT TO 14000FT. THE LT GEN DID RESET AND WORKED PROPERLY ON THE THIRD RESET. AIRCRAFT CONTINUED. MAINT INSPECTED THE AIRCRAFT AND ON PULLING THE COWLING, NOTICED SMALL METAL WIRE PARTS FALLING OUT. THE PARTS WERE FOUND TO BE THE WINDINGS FROM THE RT GENERATOR. THE GENERATOR WAS REMOVED AND FOUND TO HAVE A SHEARED SHAFT. UPON FURTHER INSPECTION, FOUND THE RT CURRENT LIMITER WAS BLOWN AND THE TORLON INSERT IN THE GEARBOX TO THE GENERATOR WAS DAMAGED. THE RT INSERT, CURRENT LIMITER, AND GENERATOR WERE REPLACED. GENERATORS WERE PARALLELED, AND OPERATIONAL CHECK OF LT AND RT DC GENERATION SYSTEMS WERE GOOD. NO FURTHER DAMAGE OR ISSUES NOTED. AIRCRAFT WAS RETURNED TO SERVICE.