Engine fire extinguisher cartridge wiring connections

Effectivity: Learjet 40/45-70/75  

ATA Code: 26 - Fire Protection 

By: Chris Hyde - Technical Services

Proper installation of the fire extinguisher cartridge wiring is critical to the operation of the fire protection system. Incorrect installation of the cartridge wiring could cause inadvertent suppressant discharge into the opposite engine cowling than desired.    

When performing any maintenance on the fire protection system that requires the removal of the cartridge wiring, following proper maintenance practices as follows can reduce the probability of maintenance errors:  

• Wiring service loops should be routed so that the connectors can only be installed on the intended cartridge, ensuring the wire label number corresponds to the correct cartridge location per the Learjet Wiring Manual. 

• If required, place temporary labeling on wiring before removal to ensure correct reinstallation onto cartridges. No additional testing can be performed after installation to ensure proper relation of the wiring to the cartridges, so correct location of the connections is essential.   

 For additional information or questions, please contact your regional Field Service Representative.