Narrative:

We were on a left downwind leg abeam the 'numbers' when the captain called for 'gear down; landing checks; props full forward' as per company policy and procedure. When the captain placed the landing gear handle down; the landing gear relay circuit breaker immediately popped. The captain immediately notified me of the situation as I am unable to see the circuit breaker from my seat. The captain told me to standby and to broadcast over the CTAF that we were going to extend our downwind leg. The captain then called for the 'circuit break tripped' abnormal checklist which reads: 1. Non-essential circuit....do not reset in flight 2. Essential circuit (necessary for continued safe flight): a. Circuit breaker (after allowing to cool for a minimum of 10 seconds)......push to reset b. If circuit breaker trips again.......do not reset. The landing gear relay circuit breaker is an essential circuit as it is part of the landing gear system. The captain shared with me her prior knowledge of knowing that if this exact circuit breaker were to be found tripped on the ground; the aircraft would be grounded as it is a not a part of the minimum equipment list (MEL). Through discussion; we both agreed that it was an essential circuit for safe flight and after following the company checklist pushed the circuit breaker back in; however; the circuit breaker immediately tripped again. As the checklist did not resolve the problem; the 'landing gear manual extension' abnormal checklist was then called for and completed. The proper authorities; such as dispatch; maintenance; assistant chief pilot and operations were well aware of the event during and after touchdown. After a successful landing; the proper personnel were notified and the event was logged with maintenance in the aircraft logbook. Company policies and procedures clearly note that if the circuit breaker is essential to a safe flight; then it will be reset. The captain and I used our knowledge and training and followed company policy and procedures for a tripped circuit breaker. The company does not have a 'list' of what is considered essential and non-essential circuit breakers; therefore; the knowledge and training of the crew is imperative in making the correct judgment. The landing gear is essential for a safe flight and landing.

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Original NASA ASRS Text

Title: B1900 flight crew reports failure of the landing gear to extend during approach due to the landing gear control circuit breaker tripping. The circuit breaker is reset and immediately trips again. Manual gear extension procedures are used and a normal landing ensues.

Narrative: We were on a left downwind leg abeam the 'numbers' when the Captain called for 'gear down; landing checks; props full forward' as per company policy and procedure. When the Captain placed the landing gear handle down; the landing gear relay circuit breaker immediately popped. The Captain immediately notified me of the situation as I am unable to see the circuit breaker from my seat. The Captain told me to standby and to broadcast over the CTAF that we were going to extend our downwind leg. The Captain then called for the 'Circuit Break Tripped' abnormal checklist which reads: 1. Non-essential Circuit....DO NOT RESET IN FLIGHT 2. Essential Circuit (Necessary for continued safe flight): a. Circuit Breaker (after allowing to cool for a minimum of 10 seconds)......PUSH TO RESET b. If Circuit Breaker trips again.......DO NOT RESET. The landing gear relay circuit breaker is an essential circuit as it is part of the landing gear system. The Captain shared with me her prior knowledge of knowing that if this exact circuit breaker were to be found tripped on the ground; the aircraft would be grounded as it is a not a part of the Minimum Equipment list (MEL). Through discussion; we both agreed that it was an essential circuit for safe flight and after following the company checklist pushed the circuit breaker back in; however; the Circuit Breaker immediately tripped again. As the checklist did not resolve the problem; the 'Landing Gear Manual Extension' abnormal checklist was then called for and completed. The proper authorities; such as Dispatch; Maintenance; Assistant Chief Pilot and Operations were well aware of the event during and after touchdown. After a successful landing; the proper personnel were notified and the event was logged with Maintenance in the aircraft logbook. Company policies and procedures clearly note that if the circuit breaker is essential to a safe flight; then it will be reset. The Captain and I used our knowledge and training and followed company policy and procedures for a tripped circuit breaker. The Company does not have a 'list' of what is considered essential and non-essential circuit breakers; therefore; the knowledge and training of the crew is imperative in making the correct judgment. The Landing Gear is essential for a safe flight and landing.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.