Narrative:

During each of the 3 downwind legs student lowered the gear and I called for a 'gump' check which the pilot performed and I verified 3 green lights to indicate gear down and locked. In addition to the downwind 'gump' check I requested student to perform a 'gump' check on final which he had successfully performed on the previous two lndgs. On the last downwind report the tower instructed us to follow an aircraft preceeding us to land. As our aircraft turned base, I pointed out to student that the projected glide path would not provide proper clearance due to a commercial jet holding between runways 19L and 19R. At this point I took control and reestablished the aircraft on the proper glide path. I called for final 'gump' check about 1/2 mi out. From the time the aircraft was approximately midbase through landing neither the pilot or myself heard any transmission from the tower. This is not unusual on a saturday when traffic is light on runway 19L and an aircraft is cleared to land either downwind or on base and no further xmissions are heard until the aircraft lands and is instructed to contact ground control. As the aircraft passed over the jet's tail I reduced the power to idle as a final check of the landing gear being down and locked, since a 90 HZ beeping warning horn will activate if the throttle is below about 14' of manifold pressure with the gear up. During the round out and flare the aircraft settled onto the runway gear up and slid a few hundred ft and came to a stop.

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Original NASA ASRS Text

Title: SMA MADE GEAR UP LNDG. ALSO, ACFT HAD NOT BEEN CLEARED TO LAND.

Narrative: DURING EACH OF THE 3 DOWNWIND LEGS STUDENT LOWERED THE GEAR AND I CALLED FOR A 'GUMP' CHK WHICH THE PLT PERFORMED AND I VERIFIED 3 GREEN LIGHTS TO INDICATE GEAR DOWN AND LOCKED. IN ADDITION TO THE DOWNWIND 'GUMP' CHK I REQUESTED STUDENT TO PERFORM A 'GUMP' CHK ON FINAL WHICH HE HAD SUCCESSFULLY PERFORMED ON THE PREVIOUS TWO LNDGS. ON THE LAST DOWNWIND RPT THE TWR INSTRUCTED US TO FOLLOW AN ACFT PRECEEDING US TO LAND. AS OUR ACFT TURNED BASE, I POINTED OUT TO STUDENT THAT THE PROJECTED GLIDE PATH WOULD NOT PROVIDE PROPER CLRNC DUE TO A COMMERCIAL JET HOLDING BTWN RWYS 19L AND 19R. AT THIS POINT I TOOK CTL AND REESTABLISHED THE ACFT ON THE PROPER GLIDE PATH. I CALLED FOR FINAL 'GUMP' CHK ABOUT 1/2 MI OUT. FROM THE TIME THE ACFT WAS APPROX MIDBASE THROUGH LNDG NEITHER THE PLT OR MYSELF HEARD ANY XMISSION FROM THE TWR. THIS IS NOT UNUSUAL ON A SATURDAY WHEN TFC IS LIGHT ON RWY 19L AND AN ACFT IS CLRED TO LAND EITHER DOWNWIND OR ON BASE AND NO FURTHER XMISSIONS ARE HEARD UNTIL THE ACFT LANDS AND IS INSTRUCTED TO CONTACT GND CTL. AS THE ACFT PASSED OVER THE JET'S TAIL I REDUCED THE PWR TO IDLE AS A FINAL CHK OF THE LNDG GEAR BEING DOWN AND LOCKED, SINCE A 90 HZ BEEPING WARNING HORN WILL ACTIVATE IF THE THROTTLE IS BELOW ABOUT 14' OF MANIFOLD PRESSURE WITH THE GEAR UP. DURING THE ROUND OUT AND FLARE THE ACFT SETTLED ONTO THE RWY GEAR UP AND SLID A FEW HUNDRED FT AND CAME TO A STOP.

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.