Circuit Breakers

Pitot heat switch would not stay in the on position. On troubleshooting, the technician found circuit breaker/switch (p/n 35-38013263) to be at fault. AD 2008-13-17 had been completed 2427 flight hours prior. Recommend breaker manufacturer develop a more durable product or aircraft maker look for a different source for its circuit breakers.

Editorial Staff

Monday, October 24, 2016 at 12:00 AM ET

Verified

Key Takeaways:

Circuit breakers in various aircraft models experienced diverse failures, ranging from mechanical issues (e.g., not staying engaged, cracked housing) to electrical malfunctions (e.g., tripping prematurely or failing to trip when overloaded).
These failures led to significant operational issues, including loss of critical systems (e.g., pitot/propeller heat), complete bus power loss, arcing, or internal electrical problems.
Incidents suggest issues with circuit breaker durability and highlight the potential for cascading failures, as well as the impact of external factors like insect contamination on electrical systems.