B737-300
Flight Crew Air Transport Pilot (ATP)
Confusion; Training / Qualification; Troubleshooting; Workload
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew FLC Overrode Automation; Flight Crew Took Evasive Action; Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft; Procedure; Chart Or Publication
When the pilot flying called for 'landing gear up;' the pilot monitoring was unable to raise the gear handle above the OFF position.  This was while flying a departure with an immediate turn to intercept a radial; with more turns shortly thereafter; and altitude restrictions; in an older model aircraft with no map display.  It required undivided attention and navigation system management by both pilots.  A quick decision was made to pull the solenoid trigger to get the gear up and stabilize the navigation and rapid-fire communication situation; and then we would go to the QRH at that time.  It should be added here that after the debrief; the pilot flying did not know it was against QRH procedure to use the Manual Solenoid Release to raise the gear; and the pilot monitoring had only a vague recollection after the fact; from past study; that there was a situation in which using the release trigger was not correct procedure.  With the gear now up and indicating up; and all known related systems behaving normally; it was decided to wait until above 10;000 feet and no longer in sterile cockpit to consult the QRH.  It was there that we learned that we should not have used the Manual Solenoid Release to raise the gear; and that there was what is essentially a 'flight test procedure' to follow in order to determine the specific system that failed.  In our case; this would have involved coordinating a flight test area with ATC; lowering the gear again above 10;000 feet to commence a QRH procedure that was supposed to be performed before raising the gear in the first place; and possibly pulling circuit breakers; and an overweight landing back in an extremely congested ATC environment.  Since the gear was already up; the QRH reviewed; aircraft was operating normally; and the destination was a Company Maintenance Base/Station; we decided to continue and not use the speedbrakes in case the situation was due to air/ground system failure or ground spoiler bypass valve failure.  Maintenance was notified enroute and the flight proceeded to an uneventful landing.  Upon meeting the Mechanic at the gate; he discovered a circuit breaker in the tripped position and informed us that that would cause the gear handle not to raise above OFF. There was more than one error.  The first being that we used the lever lock to raise the gear in the first place.  If the crew had a more comprehensive knowledge of the non-memory items in the QRH; the gear would not have been raised.  The popped circuit breaker that caused the gear handle not to raise was out of the normal field of view of the pilot flying and was shrouded by the intentionally (blue) collared breaker right next to it from the pilot monitoring's perspective.  A more diligent look by the pilot monitoring once airborne would have caught it. But then what?  It is policy that a tripped circuit breaker not be reset unless; in the opinion of the PIC; it is critical to the safe conduct of the flight.  Is that circuit breaker critical? What do you do if you've already got the gear up (contrary to the QRH guidance) and the find the tripped breaker?  Do you automatically reset it?  It seems fairly evident from the location of that particular circuit breaker; that it was inadvertently tripped by an overly rapid First Officer's seatbelt retraction.  Perhaps some sort of shield could be fabricated to prevent such a thing or a dash pot/damper to slow the rapid retraction of the belt.
A B737-300 crew used the Landing Gear Manual Solenoid Release to raise a non-responsive landing gear and while completing the QRH determined that was an unauthorized procedure. After landing; Maintenance discovered a tripped landing gear circuit breaker caused the problem.