Narrative:

While engaged in multi-engine instructor training in the traffic pattern at the ttn airport, and while on landing flare, the propeller tips of the left engine contacted the runway and were damaged. I was being trained by a multi-engine instructor, rated in the aircraft at the time. The landing gear had inadvertently been left in the retracted position, due to the distrs associated with a simulated engine failure in the traffic pattern, combined with a short approach and landing. Contributing factors were the difficulty controling the aircraft while simulating an engine securing procedure with windy conditions (13+ KTS) and gusts (20+ KTS) as well as occasional moderate turbulence below 3000 ft MSL, which added to the distrs. Additionally, the very bright sunshine glaring off the instrument panel made it impossible to see either the 'gear unsafe' warning light, or the 3 'gear down safe' lights off. Also the gear up warning horn was not heard either because it was not triggered, though the power was below the 15 inches manifold pressure point, or because of the standard cockpit and communications noise. The combined distrs of the nonstandard approach and landing, as well as the existing environmental conditions, resulted in the damage to the left engine propeller tips. The instructor quickly recognized an unusual situation and promptly executed a go around for a normal landing. Since the aircraft operated as normal during the go around, it was thought that it had been the underside of the tail tip or one of the belly antennas that had contacted the runway. It was later discovered, after engine shutdown, that the propeller tips on the left engine had been damaged, and had curled back about 1 inch.

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Original NASA ASRS Text

Title: A FLT INSTRUCTOR AND HIS STUDENT AT TTN FLYING A PA44-180 FAILED TO LOWER THE LNDG GEAR DURING APCH AND STRUCK THE L PROP WHILE ATTEMPTING TO LAND.

Narrative: WHILE ENGAGED IN MULTI-ENG INSTRUCTOR TRAINING IN THE TFC PATTERN AT THE TTN ARPT, AND WHILE ON LNDG FLARE, THE PROP TIPS OF THE L ENG CONTACTED THE RWY AND WERE DAMAGED. I WAS BEING TRAINED BY A MULTI-ENG INSTRUCTOR, RATED IN THE ACFT AT THE TIME. THE LNDG GEAR HAD INADVERTENTLY BEEN LEFT IN THE RETRACTED POS, DUE TO THE DISTRS ASSOCIATED WITH A SIMULATED ENG FAILURE IN THE TFC PATTERN, COMBINED WITH A SHORT APCH AND LNDG. CONTRIBUTING FACTORS WERE THE DIFFICULTY CTLING THE ACFT WHILE SIMULATING AN ENG SECURING PROC WITH WINDY CONDITIONS (13+ KTS) AND GUSTS (20+ KTS) AS WELL AS OCCASIONAL MODERATE TURB BELOW 3000 FT MSL, WHICH ADDED TO THE DISTRS. ADDITIONALLY, THE VERY BRIGHT SUNSHINE GLARING OFF THE INST PANEL MADE IT IMPOSSIBLE TO SEE EITHER THE 'GEAR UNSAFE' WARNING LIGHT, OR THE 3 'GEAR DOWN SAFE' LIGHTS OFF. ALSO THE GEAR UP WARNING HORN WAS NOT HEARD EITHER BECAUSE IT WAS NOT TRIGGERED, THOUGH THE PWR WAS BELOW THE 15 INCHES MANIFOLD PRESSURE POINT, OR BECAUSE OF THE STANDARD COCKPIT AND COMS NOISE. THE COMBINED DISTRS OF THE NONSTANDARD APCH AND LNDG, AS WELL AS THE EXISTING ENVIRONMENTAL CONDITIONS, RESULTED IN THE DAMAGE TO THE L ENG PROP TIPS. THE INSTRUCTOR QUICKLY RECOGNIZED AN UNUSUAL SIT AND PROMPTLY EXECUTED A GAR FOR A NORMAL LNDG. SINCE THE ACFT OPERATED AS NORMAL DURING THE GAR, IT WAS THOUGHT THAT IT HAD BEEN THE UNDERSIDE OF THE TAIL TIP OR ONE OF THE BELLY ANTENNAS THAT HAD CONTACTED THE RWY. IT WAS LATER DISCOVERED, AFTER ENG SHUTDOWN, THAT THE PROP TIPS ON THE L ENG HAD BEEN DAMAGED, AND HAD CURLED BACK ABOUT 1 INCH.

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.