Narrative:

The incident involved an small aircraft. The purpose of the flight was to maintain proficiency and was restr to the traffic pattern for takeoff and lndgs. This aircraft is equipped with an automatic gear extension system which will lower the gear or prevent its retraction if the airspeed is below approximately 100 KTS. It was placed in override and deactivated. The gear down lights have a rheostat that is wired to the navigation/instrument lights. If the aircraft is configured for night flight, the intensity of the gear lights are greatly reduced. The aircraft had been configured early for night operations. The aircraft is equipped with a gear unsafe warning horn and a red light on the glareshield, however there is no recommended test procedure. On the fifth and last landing in the series, the aircraft was required to slow to lower than normal due to conflicting traffic in the pattern. A series of non standard procedures by other aircraft in the pattern distracted attention away from the normal landing checklist procedures and we directed it towards traffic avoidance. An extended downwind and an irregular pattern led to a disrupted and accelerated checklist. It was assumed that the gear was placed down at normal abeam T/D point. It was assumed that the gear was down because there was no warning indications when the throttle was retarded (used in place of gear down lights because they were not easily readable because of dimmed position). The result was a very nice 'gear up landing.' an inquiry into why there were no warnings revealed that the throttle needed to be pulled hard against the idle stop to activate the horn and the red warning on the glareshield had vibrated loose from its electrical contacts. In summary, there were 2 qualified pilots on board this aircraft, and both were lulled away from using standard procedures. Pilots cannot afford to be complacent in their assumption--it can be a subtle killer.

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Original NASA ASRS Text

Title: GA SMA GEAR UP LNDG.

Narrative: THE INCIDENT INVOLVED AN SMA. THE PURPOSE OF THE FLT WAS TO MAINTAIN PROFICIENCY AND WAS RESTR TO THE TFC PATTERN FOR TKOF AND LNDGS. THIS ACFT IS EQUIPPED WITH AN AUTOMATIC GEAR EXTENSION SYS WHICH WILL LOWER THE GEAR OR PREVENT ITS RETRACTION IF THE AIRSPD IS BELOW APPROX 100 KTS. IT WAS PLACED IN OVERRIDE AND DEACTIVATED. THE GEAR DOWN LIGHTS HAVE A RHEOSTAT THAT IS WIRED TO THE NAV/INSTRUMENT LIGHTS. IF THE ACFT IS CONFIGURED FOR NIGHT FLT, THE INTENSITY OF THE GEAR LIGHTS ARE GREATLY REDUCED. THE ACFT HAD BEEN CONFIGURED EARLY FOR NIGHT OPS. THE ACFT IS EQUIPPED WITH A GEAR UNSAFE WARNING HORN AND A RED LIGHT ON THE GLARESHIELD, HOWEVER THERE IS NO RECOMMENDED TEST PROC. ON THE FIFTH AND LAST LNDG IN THE SERIES, THE ACFT WAS REQUIRED TO SLOW TO LOWER THAN NORMAL DUE TO CONFLICTING TFC IN THE PATTERN. A SERIES OF NON STANDARD PROCS BY OTHER ACFT IN THE PATTERN DISTRACTED ATTN AWAY FROM THE NORMAL LNDG CHKLIST PROCS AND WE DIRECTED IT TOWARDS TFC AVOIDANCE. AN EXTENDED DOWNWIND AND AN IRREGULAR PATTERN LED TO A DISRUPTED AND ACCELERATED CHKLIST. IT WAS ASSUMED THAT THE GEAR WAS PLACED DOWN AT NORMAL ABEAM T/D POINT. IT WAS ASSUMED THAT THE GEAR WAS DOWN BECAUSE THERE WAS NO WARNING INDICATIONS WHEN THE THROTTLE WAS RETARDED (USED IN PLACE OF GEAR DOWN LIGHTS BECAUSE THEY WERE NOT EASILY READABLE BECAUSE OF DIMMED POS). THE RESULT WAS A VERY NICE 'GEAR UP LNDG.' AN INQUIRY INTO WHY THERE WERE NO WARNINGS REVEALED THAT THE THROTTLE NEEDED TO BE PULLED HARD AGAINST THE IDLE STOP TO ACTIVATE THE HORN AND THE RED WARNING ON THE GLARESHIELD HAD VIBRATED LOOSE FROM ITS ELECTRICAL CONTACTS. IN SUMMARY, THERE WERE 2 QUALIFIED PLTS ON BOARD THIS ACFT, AND BOTH WERE LULLED AWAY FROM USING STANDARD PROCS. PLTS CANNOT AFFORD TO BE COMPLACENT IN THEIR ASSUMPTION--IT CAN BE A SUBTLE KILLER.

Data retrieved from NASA's ASRS site as of August 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.