Narrative:

The departure and en route portions of the flight were uneventful. The winds in mry were reported calm and we were cleared for a visual approach to runway 28L. I was flying the aircraft. During the final segment of the approach I selected the flaps to 35 degrees to create more drag, because even with the power levers all the way back to flight idle, the right engine was still producing 23 percent torque. We touched down at the flap 35 degree reference speed approximately 1500 ft down the runway. After touchdown the blue flight idle stop light did not illuminate and I could not move the power levers into ground idle or reverse. I tried pushing forward on the yoke in an attempt to put more pressure on the wheels, but the light would still not come on and the power levers would not go into ground idle. By that time, due to the fact that it is a down hill sloping runway and our right engine was still producing power. I was unsure as to whether or not we could stop on the runway with brakes only. I opted to apply full power and execute a missed approach. On the next approach we landed on the uphill sloping runway 10R with flaps 20 degrees. The blue flight idle stop light came on and ground idle and reverse power were available. We taxied to the gate with no further incident. After deplaning I noticed that the winds appeared to be out of the east at somewhere around 5 KTS. I know that pulling the flight idle stop override would have probably released the power levers allowing for reverse power. However, while rolling down the runway at 105 KTS there simply was not enough time to go through that whole thought process and procedure, and furthermore, had the flight idle stop override not worked, we would have had no options left. Additionally all of our landing distance data is predicated on at least ground idle being available. In this case we couldn't even get ground idle, and therefore the airplane was not slowing at all while on the runway. In light of this incident and other problems that I have witnessed and heard of, I strongly believe that the flight idle stop is one of the most dangerous pieces of equipment that I have ever seen installed on an aircraft, and that sooner or later someone will go off the end of a runway because of it. Callback conversation with reporter revealed the following information: reporter captain attributes several possible factors to the failure of the flight idle stop from functioning normally: use of 35 degree flaps may have shifted the center of gravity far enough rearward which kept the aircraft weight off the wheels too long. The down hill slope of the runway, which added to the ground speed. Again, weight off the wheels, faulty strut or wheel spin up switch which provides the signal for the flight idle stop, engines misrigged to a higher idle power setting. Though the aircraft has a flight idle stop override switch, reporter says there wasn't enough time to pull it. Reporter says this failure of the flight idle stop occurred another time within the past few months. He recommends that the problem should first be fixed so there won't be surprise failures of the flight idle stop and, in the meantime the airlines should train their pilots to be better prepared to use the override. To do that, he suggests that the PF has his hand on the override on landing as well as the PNF monitoring the blue flight idle stop light and advise the PF immediately of the light off, so the override can be immediately used. There also has been other incidents of misrigging of the power lever quadrant which may also be the cause.

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Original NASA ASRS Text

Title: SAAB 340B ACFT. AFTER LNDG THE FLT IDLE STOP LIGHT DID NOT ILLUMINATE AND RPTR CAPT COULDN'T PWR LEVERS INTO GND IDLE. NOT ENOUGH TIME TO PULL FLT IDLE STOP OVERRIDE, SO RPTR EXECUTED A GAR. NEXT LNDG WAS UPSLOPE WITH LESS FLAP SETTING AND FLT IDLE STOP WORKED NORMALLY.

Narrative: THE DEP AND ENRTE PORTIONS OF THE FLT WERE UNEVENTFUL. THE WINDS IN MRY WERE RPTED CALM AND WE WERE CLRED FOR A VISUAL APCH TO RWY 28L. I WAS FLYING THE ACFT. DURING THE FINAL SEGMENT OF THE APCH I SELECTED THE FLAPS TO 35 DEGS TO CREATE MORE DRAG, BECAUSE EVEN WITH THE PWR LEVERS ALL THE WAY BACK TO FLT IDLE, THE R ENG WAS STILL PRODUCING 23 PERCENT TORQUE. WE TOUCHED DOWN AT THE FLAP 35 DEG REF SPD APPROX 1500 FT DOWN THE RWY. AFTER TOUCHDOWN THE BLUE FLT IDLE STOP LIGHT DID NOT ILLUMINATE AND I COULD NOT MOVE THE PWR LEVERS INTO GND IDLE OR REVERSE. I TRIED PUSHING FORWARD ON THE YOKE IN AN ATTEMPT TO PUT MORE PRESSURE ON THE WHEELS, BUT THE LIGHT WOULD STILL NOT COME ON AND THE PWR LEVERS WOULD NOT GO INTO GND IDLE. BY THAT TIME, DUE TO THE FACT THAT IT IS A DOWN HILL SLOPING RWY AND OUR R ENG WAS STILL PRODUCING PWR. I WAS UNSURE AS TO WHETHER OR NOT WE COULD STOP ON THE RWY WITH BRAKES ONLY. I OPTED TO APPLY FULL PWR AND EXECUTE A MISSED APCH. ON THE NEXT APCH WE LANDED ON THE UPHILL SLOPING RWY 10R WITH FLAPS 20 DEGS. THE BLUE FLT IDLE STOP LIGHT CAME ON AND GND IDLE AND REVERSE PWR WERE AVAILABLE. WE TAXIED TO THE GATE WITH NO FURTHER INCIDENT. AFTER DEPLANING I NOTICED THAT THE WINDS APPEARED TO BE OUT OF THE E AT SOMEWHERE AROUND 5 KTS. I KNOW THAT PULLING THE FLT IDLE STOP OVERRIDE WOULD HAVE PROBABLY RELEASED THE PWR LEVERS ALLOWING FOR REVERSE PWR. HOWEVER, WHILE ROLLING DOWN THE RWY AT 105 KTS THERE SIMPLY WAS NOT ENOUGH TIME TO GO THROUGH THAT WHOLE THOUGHT PROCESS AND PROC, AND FURTHERMORE, HAD THE FLT IDLE STOP OVERRIDE NOT WORKED, WE WOULD HAVE HAD NO OPTIONS LEFT. ADDITIONALLY ALL OF OUR LNDG DISTANCE DATA IS PREDICATED ON AT LEAST GND IDLE BEING AVAILABLE. IN THIS CASE WE COULDN'T EVEN GET GND IDLE, AND THEREFORE THE AIRPLANE WAS NOT SLOWING AT ALL WHILE ON THE RWY. IN LIGHT OF THIS INCIDENT AND OTHER PROBS THAT I HAVE WITNESSED AND HEARD OF, I STRONGLY BELIEVE THAT THE FLT IDLE STOP IS ONE OF THE MOST DANGEROUS PIECES OF EQUIP THAT I HAVE EVER SEEN INSTALLED ON AN ACFT, AND THAT SOONER OR LATER SOMEONE WILL GO OFF THE END OF A RWY BECAUSE OF IT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CAPT ATTRIBUTES SEVERAL POSSIBLE FACTORS TO THE FAILURE OF THE FLT IDLE STOP FROM FUNCTIONING NORMALLY: USE OF 35 DEG FLAPS MAY HAVE SHIFTED THE CTR OF GRAVITY FAR ENOUGH REARWARD WHICH KEPT THE ACFT WT OFF THE WHEELS TOO LONG. THE DOWN HILL SLOPE OF THE RWY, WHICH ADDED TO THE GND SPD. AGAIN, WT OFF THE WHEELS, FAULTY STRUT OR WHEEL SPIN UP SWITCH WHICH PROVIDES THE SIGNAL FOR THE FLT IDLE STOP, ENGS MISRIGGED TO A HIGHER IDLE PWR SETTING. THOUGH THE ACFT HAS A FLT IDLE STOP OVERRIDE SWITCH, RPTR SAYS THERE WASN'T ENOUGH TIME TO PULL IT. RPTR SAYS THIS FAILURE OF THE FLT IDLE STOP OCCURRED ANOTHER TIME WITHIN THE PAST FEW MONTHS. HE RECOMMENDS THAT THE PROB SHOULD FIRST BE FIXED SO THERE WON'T BE SURPRISE FAILURES OF THE FLT IDLE STOP AND, IN THE MEANTIME THE AIRLINES SHOULD TRAIN THEIR PLTS TO BE BETTER PREPARED TO USE THE OVERRIDE. TO DO THAT, HE SUGGESTS THAT THE PF HAS HIS HAND ON THE OVERRIDE ON LNDG AS WELL AS THE PNF MONITORING THE BLUE FLT IDLE STOP LIGHT AND ADVISE THE PF IMMEDIATELY OF THE LIGHT OFF, SO THE OVERRIDE CAN BE IMMEDIATELY USED. THERE ALSO HAS BEEN OTHER INCIDENTS OF MISRIGGING OF THE PWR LEVER QUADRANT WHICH MAY ALSO BE THE CAUSE.

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.