Narrative:

While doing before taxi check, noted 0 psi hydraulic pressure on #2 engine. As per company procedure, I checked annunciator panel to determine which checklist to consult for this situation and noted #2 AC generator caution light was also on. We cycled the #2 AC generator switch off then on, and also tried a circuit breaker reset and were unable to restore the situation to normal. Both the hydraulic pump and AC generator operate off an accessory case driven from the propeller reduction gear box. Normally I would have shut the engine down at this point. However, in this case a company instructor was riding in the cabin and I requested he come up front and possibly give me some insight on what the source of the problem might be. He noted immediately that the propeller tachometer was reading 0 RPM. The other engine instruments, torque, itt, nh (N1) were normal. Upon looking out the window, saw that the propeller was stopped. The engine was shut down at this point. An external inspection was made and we were unable to move the propeller initially but several mins later upon checking the propeller again it was tree and approach to spin normally. I then contacted company maintenance by phone. I described the proceeding situation, and stated that it was my thought that this whole scenario reverted back to the AC generator possibly being hung up. So the write-up in the logbook would be '#2 AC generator inoperative.' my thought when submitting this write-up, was that it would suffice to get the maintenance process started. The mechanic I talked to in our maintenance operations control center told me he didn't know either what might have caused our situation, and because the propeller had seized would contact his supervisor. I then met with the mechanics (contract) who had been contacted by our company to look at the airplane. I described everything that had happened and he stated that he didn't have an idea either what the cause of this problem could be. Company maintenance then told us to do an engine start. Watch the gauges carefully for any anomalies, and see if the problem would recur. The engine was then started and all gauges and system operated normally. After running the engine for about 10 mins with various power and propeller configns, the decision was made between our company and contract maintenance to sign off the write-up as 'ground checks ok, could not duplicate.' I agreed to accept the aircraft. Normal operations were resumed. At this point, a week later I am unaware of any further problem with this aircraft. As I reflect, I have several concerns with my actions: 1) on engine start, I can't unequivocally state that the #2 propeller tachometer was showing rotation. That gauge is part of the normal scan during start. The first officer stated he was certain he saw it turning. Also, the ground man who gave us the 'clear to start' told me the propeller was turning. Starting engines is such a common procedure. Through complacency I can't specifically remember what this specific gauge was doing during start. 2) I became confused with an abnormal situation I hadn't encountered before nor had training for. While focusing on the AC system and #2 hydraulic system, I forgot about the rest of the aircraft (basic engine gauges). 3) because I felt there was someone available (the company instructor) to help me out, I delayed doing the obvious and proper thing -- shutting the engine down. 4) my discrepancy write-up was improper. As a pilot my write- up should have been descriptive rather than diagnostic. My main concern at the time was to get someone on the job. Because of my lingering confusion as to what had happened I didn't want to put too much in writing. 5) the mechanics signed off the airplane without pulling the cowling, and looking for something amiss. I thought about this at the time, and rationalized -- if there was engine damage, it would probably be in the reduction gears and show up in the engine readings. Plus it would have required a shutdown and another restart, plus we were behind schedule, plus I felt some personal guilt that I might have screwed up by possibly failing to note the propeller not turning during start.

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Original NASA ASRS Text

Title: MDT ACFT HAD PROB WITH #2 ENG DURING START. 0 HYD PRESSURE AND #2 GENERATOR CAUTION LIGHT ON. CAPT RPTR CALLED AN INSTRUCTOR PLT WHO WAS IN THE CABIN TO LOOK AT THE SIT AND THE INSTRUCTOR NOTED IMMEDIATELY THAT THE PROP WAS NOT TURNING. THE ENG WAS SHUT DOWN, MECHS CHKED IT AND ON RESTART ALL SYS OPERATED NORMALLY.

Narrative: WHILE DOING BEFORE TAXI CHK, NOTED 0 PSI HYD PRESSURE ON #2 ENG. AS PER COMPANY PROC, I CHKED ANNUNCIATOR PANEL TO DETERMINE WHICH CHKLIST TO CONSULT FOR THIS SIT AND NOTED #2 AC GENERATOR CAUTION LIGHT WAS ALSO ON. WE CYCLED THE #2 AC GENERATOR SWITCH OFF THEN ON, AND ALSO TRIED A CIRCUIT BREAKER RESET AND WERE UNABLE TO RESTORE THE SIT TO NORMAL. BOTH THE HYD PUMP AND AC GENERATOR OPERATE OFF AN ACCESSORY CASE DRIVEN FROM THE PROP REDUCTION GEAR BOX. NORMALLY I WOULD HAVE SHUT THE ENG DOWN AT THIS POINT. HOWEVER, IN THIS CASE A COMPANY INSTRUCTOR WAS RIDING IN THE CABIN AND I REQUESTED HE COME UP FRONT AND POSSIBLY GIVE ME SOME INSIGHT ON WHAT THE SOURCE OF THE PROB MIGHT BE. HE NOTED IMMEDIATELY THAT THE PROP TACHOMETER WAS READING 0 RPM. THE OTHER ENG INSTS, TORQUE, ITT, NH (N1) WERE NORMAL. UPON LOOKING OUT THE WINDOW, SAW THAT THE PROP WAS STOPPED. THE ENG WAS SHUT DOWN AT THIS POINT. AN EXTERNAL INSPECTION WAS MADE AND WE WERE UNABLE TO MOVE THE PROP INITIALLY BUT SEVERAL MINS LATER UPON CHKING THE PROP AGAIN IT WAS TREE AND APCH TO SPIN NORMALLY. I THEN CONTACTED COMPANY MAINT BY PHONE. I DESCRIBED THE PROCEEDING SIT, AND STATED THAT IT WAS MY THOUGHT THAT THIS WHOLE SCENARIO REVERTED BACK TO THE AC GENERATOR POSSIBLY BEING HUNG UP. SO THE WRITE-UP IN THE LOGBOOK WOULD BE '#2 AC GENERATOR INOP.' MY THOUGHT WHEN SUBMITTING THIS WRITE-UP, WAS THAT IT WOULD SUFFICE TO GET THE MAINT PROCESS STARTED. THE MECH I TALKED TO IN OUR MAINT OPS CTL CTR TOLD ME HE DIDN'T KNOW EITHER WHAT MIGHT HAVE CAUSED OUR SIT, AND BECAUSE THE PROP HAD SEIZED WOULD CONTACT HIS SUPVR. I THEN MET WITH THE MECHS (CONTRACT) WHO HAD BEEN CONTACTED BY OUR COMPANY TO LOOK AT THE AIRPLANE. I DESCRIBED EVERYTHING THAT HAD HAPPENED AND HE STATED THAT HE DIDN'T HAVE AN IDEA EITHER WHAT THE CAUSE OF THIS PROB COULD BE. COMPANY MAINT THEN TOLD US TO DO AN ENG START. WATCH THE GAUGES CAREFULLY FOR ANY ANOMALIES, AND SEE IF THE PROB WOULD RECUR. THE ENG WAS THEN STARTED AND ALL GAUGES AND SYS OPERATED NORMALLY. AFTER RUNNING THE ENG FOR ABOUT 10 MINS WITH VARIOUS PWR AND PROP CONFIGNS, THE DECISION WAS MADE BTWN OUR COMPANY AND CONTRACT MAINT TO SIGN OFF THE WRITE-UP AS 'GND CHKS OK, COULD NOT DUPLICATE.' I AGREED TO ACCEPT THE ACFT. NORMAL OPS WERE RESUMED. AT THIS POINT, A WK LATER I AM UNAWARE OF ANY FURTHER PROB WITH THIS ACFT. AS I REFLECT, I HAVE SEVERAL CONCERNS WITH MY ACTIONS: 1) ON ENG START, I CAN'T UNEQUIVOCALLY STATE THAT THE #2 PROP TACHOMETER WAS SHOWING ROTATION. THAT GAUGE IS PART OF THE NORMAL SCAN DURING START. THE FO STATED HE WAS CERTAIN HE SAW IT TURNING. ALSO, THE GND MAN WHO GAVE US THE 'CLR TO START' TOLD ME THE PROP WAS TURNING. STARTING ENGS IS SUCH A COMMON PROC. THROUGH COMPLACENCY I CAN'T SPECIFICALLY REMEMBER WHAT THIS SPECIFIC GAUGE WAS DOING DURING START. 2) I BECAME CONFUSED WITH AN ABNORMAL SIT I HADN'T ENCOUNTERED BEFORE NOR HAD TRAINING FOR. WHILE FOCUSING ON THE AC SYS AND #2 HYD SYS, I FORGOT ABOUT THE REST OF THE ACFT (BASIC ENG GAUGES). 3) BECAUSE I FELT THERE WAS SOMEONE AVAILABLE (THE COMPANY INSTRUCTOR) TO HELP ME OUT, I DELAYED DOING THE OBVIOUS AND PROPER THING -- SHUTTING THE ENG DOWN. 4) MY DISCREPANCY WRITE-UP WAS IMPROPER. AS A PLT MY WRITE- UP SHOULD HAVE BEEN DESCRIPTIVE RATHER THAN DIAGNOSTIC. MY MAIN CONCERN AT THE TIME WAS TO GET SOMEONE ON THE JOB. BECAUSE OF MY LINGERING CONFUSION AS TO WHAT HAD HAPPENED I DIDN'T WANT TO PUT TOO MUCH IN WRITING. 5) THE MECHS SIGNED OFF THE AIRPLANE WITHOUT PULLING THE COWLING, AND LOOKING FOR SOMETHING AMISS. I THOUGHT ABOUT THIS AT THE TIME, AND RATIONALIZED -- IF THERE WAS ENG DAMAGE, IT WOULD PROBABLY BE IN THE REDUCTION GEARS AND SHOW UP IN THE ENG READINGS. PLUS IT WOULD HAVE REQUIRED A SHUTDOWN AND ANOTHER RESTART, PLUS WE WERE BEHIND SCHEDULE, PLUS I FELT SOME PERSONAL GUILT THAT I MIGHT HAVE SCREWED UP BY POSSIBLY FAILING TO NOTE THE PROP NOT TURNING DURING START.

Data retrieved from NASA's ASRS site as of July 2007 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.