Narrative:

An FAA safety inspector, requested permission to ride, and observe operations, on flight. Permission to ride and observe was granted. During the course of the departure procedures, the FAA representative asked about the yaw dampers, to which I replied that they were working. This seemed to satisfy the agent, as he made no further comments to me during the entire flight. A yaw damper check was performed during taxi using the yaw damper indices the autoplt check was good, confirming yaw damper operation, and the red warning yaw damper failure lights were out. The green yaw damper engaged lights have been very dim in this aircraft, and as this was a night time operation, they are hard to see. It was on the subsequent flight that it was realized that the green yaw damper engagement lights were both not dim, but in fact inoperative. This in no way affects the safety of the operation, as the yaw dampers were both operating, and had 3 separate checks to prove it, but since we were unaware that the green engagement lights were out on departure from cvg, we departed without placarding the lights according to our MEL. This is of course against our operating procedures, and very embarrassing with the FAA on board. The problem was found on the next flight, and turned over to our maintenance for proper handling. One of the reasons the problem was not discovered sooner, is because this aircraft, also had a continuous stick shaker in rotation, and climb out, at cvg. The only way to stop the shaker was to pull its respective circuit breaker, company was advised by and we were advised by company to land at destination (bwi). This event is one that could affect safety of flight, if not handled properly by the crew. In my opinion, my crew, and myself, handled this problem in a timely, and professional manner, at the onset of the stick shaker, full power was applied, and the aircraft flown in accordance with standard departure procedures, until it was determined that this was a nuisance failure of the stall warning system. Upon landing at destination, it was found that the stall warning computer was bad. It was replaced by maintenance, and tested as operational, prior to the next departure. I have initiated this report in an effort to explain my actions, and that of my crew, with respect to these multiple failures, and to alleviate any confusion that might rise as to our actions.

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Original NASA ASRS Text

Title: ACFT FLOWN ILLEGALLY WITH YAW DAMPER INDICATOR LIGHTS INOPERATIVE.

Narrative: AN FAA SAFETY INSPECTOR, REQUESTED PERMISSION TO RIDE, AND OBSERVE OPS, ON FLT. PERMISSION TO RIDE AND OBSERVE WAS GRANTED. DURING THE COURSE OF THE DEP PROCS, THE FAA REPRESENTATIVE ASKED ABOUT THE YAW DAMPERS, TO WHICH I REPLIED THAT THEY WERE WORKING. THIS SEEMED TO SATISFY THE AGENT, AS HE MADE NO FURTHER COMMENTS TO ME DURING THE ENTIRE FLT. A YAW DAMPER CHK WAS PERFORMED DURING TAXI USING THE YAW DAMPER INDICES THE AUTOPLT CHK WAS GOOD, CONFIRMING YAW DAMPER OP, AND THE RED WARNING YAW DAMPER FAILURE LIGHTS WERE OUT. THE GREEN YAW DAMPER ENGAGED LIGHTS HAVE BEEN VERY DIM IN THIS ACFT, AND AS THIS WAS A NIGHT TIME OP, THEY ARE HARD TO SEE. IT WAS ON THE SUBSEQUENT FLT THAT IT WAS REALIZED THAT THE GREEN YAW DAMPER ENGAGEMENT LIGHTS WERE BOTH NOT DIM, BUT IN FACT INOP. THIS IN NO WAY AFFECTS THE SAFETY OF THE OP, AS THE YAW DAMPERS WERE BOTH OPERATING, AND HAD 3 SEPARATE CHKS TO PROVE IT, BUT SINCE WE WERE UNAWARE THAT THE GREEN ENGAGEMENT LIGHTS WERE OUT ON DEP FROM CVG, WE DEPARTED WITHOUT PLACARDING THE LIGHTS ACCORDING TO OUR MEL. THIS IS OF COURSE AGAINST OUR OPERATING PROCS, AND VERY EMBARRASSING WITH THE FAA ON BOARD. THE PROBLEM WAS FOUND ON THE NEXT FLT, AND TURNED OVER TO OUR MAINT FOR PROPER HANDLING. ONE OF THE REASONS THE PROBLEM WAS NOT DISCOVERED SOONER, IS BECAUSE THIS ACFT, ALSO HAD A CONTINUOUS STICK SHAKER IN ROTATION, AND CLBOUT, AT CVG. THE ONLY WAY TO STOP THE SHAKER WAS TO PULL ITS RESPECTIVE CIRCUIT BREAKER, COMPANY WAS ADVISED BY AND WE WERE ADVISED BY COMPANY TO LAND AT DEST (BWI). THIS EVENT IS ONE THAT COULD AFFECT SAFETY OF FLT, IF NOT HANDLED PROPERLY BY THE CREW. IN MY OPINION, MY CREW, AND MYSELF, HANDLED THIS PROBLEM IN A TIMELY, AND PROFESSIONAL MANNER, AT THE ONSET OF THE STICK SHAKER, FULL PWR WAS APPLIED, AND THE ACFT FLOWN IN ACCORDANCE WITH STANDARD DEP PROCS, UNTIL IT WAS DETERMINED THAT THIS WAS A NUISANCE FAILURE OF THE STALL WARNING SYS. UPON LNDG AT DEST, IT WAS FOUND THAT THE STALL WARNING COMPUTER WAS BAD. IT WAS REPLACED BY MAINT, AND TESTED AS OPERATIONAL, PRIOR TO THE NEXT DEP. I HAVE INITIATED THIS RPT IN AN EFFORT TO EXPLAIN MY ACTIONS, AND THAT OF MY CREW, WITH RESPECT TO THESE MULTIPLE FAILURES, AND TO ALLEVIATE ANY CONFUSION THAT MIGHT RISE AS TO OUR ACTIONS.

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.