Narrative:

On student's first x-country with instructor. On downwind to 26R at phx, clearance called for left 270 degree turn from right downwind 26R to right base 26R, student allowed altitude to fall 100 ft below tpa (2100) on left turn and climb, engine sputtered then lost power. He leveled the wings and set for a best glide pitch. I informed ATC we needed direct to numbers for engine problems. We were cleared for that and landing on 26R. The glide would not permit landing on runway so I took over and attempted to re-port fuel by slipping aircraft. At 500 ft AGL I secured the engine, reestablished normal glide, and selected a final touchdown point in a field short of the runway we had turned to on extended runway centerline. Once landing was assured I added full flaps, touched down and brought the plane to a full stop. (Hard landing inspection revealed no damage to airframe/power-plant,...). In computing flight, we figured there was 1/4 tank in tanks already by use of a (later found uncalibrated) dipstick. We purchased enough fuel (any more would put flight over gross weight) for a trip to tucson international and return (plus 30 min reserve). The flight down was on schedule, but the return trip was 30 min longer than scheduled. Upon entering the pattern, I figured the reserve was gone, but we still had 1/4 tank. (6.5 gallons, 3.5 unusable, 3 gallons usable). Upon inspecting tanks at the incident scene, the dipstick read just under a 1/4 tank, but only 1 3/8 gallons was drained at the low point engine sump. (This doesn't include unusable). But it never made it to the engine in the attitude the student put the airplane into. From this I have learned that if the quantity is very low, land immediately. (Do not push a flight to the last few gallons). Do not trust other than factory dipsticks. If possible, when training, fill the plane to gross weight or full tanks, which ever less after every landing (for security and student inefficiency).

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Original NASA ASRS Text

Title: OFF ARPT LNDG MADE AFTER SMA EXPERIENCES ENG FAILURE DUE TO FUEL STARVATION AND NEAR EXHAUSTION.

Narrative: ON STUDENT'S FIRST X-COUNTRY WITH INSTRUCTOR. ON DOWNWIND TO 26R AT PHX, CLRNC CALLED FOR L 270 DEG TURN FROM R DOWNWIND 26R TO R BASE 26R, STUDENT ALLOWED ALT TO FALL 100 FT BELOW TPA (2100) ON L TURN AND CLB, ENG SPUTTERED THEN LOST PWR. HE LEVELED THE WINGS AND SET FOR A BEST GLIDE PITCH. I INFORMED ATC WE NEEDED DIRECT TO NUMBERS FOR ENG PROBLEMS. WE WERE CLRED FOR THAT AND LNDG ON 26R. THE GLIDE WOULD NOT PERMIT LNDG ON RWY SO I TOOK OVER AND ATTEMPTED TO RE-PORT FUEL BY SLIPPING ACFT. AT 500 FT AGL I SECURED THE ENG, REESTABLISHED NORMAL GLIDE, AND SELECTED A FINAL TOUCHDOWN POINT IN A FIELD SHORT OF THE RWY WE HAD TURNED TO ON EXTENDED RWY CTRLINE. ONCE LNDG WAS ASSURED I ADDED FULL FLAPS, TOUCHED DOWN AND BROUGHT THE PLANE TO A FULL STOP. (HARD LNDG INSPECTION REVEALED NO DAMAGE TO AIRFRAME/PWR-PLANT,...). IN COMPUTING FLT, WE FIGURED THERE WAS 1/4 TANK IN TANKS ALREADY BY USE OF A (LATER FOUND UNCALIBRATED) DIPSTICK. WE PURCHASED ENOUGH FUEL (ANY MORE WOULD PUT FLT OVER GROSS WT) FOR A TRIP TO TUCSON INTL AND RETURN (PLUS 30 MIN RESERVE). THE FLT DOWN WAS ON SCHEDULE, BUT THE RETURN TRIP WAS 30 MIN LONGER THAN SCHEDULED. UPON ENTERING THE PATTERN, I FIGURED THE RESERVE WAS GONE, BUT WE STILL HAD 1/4 TANK. (6.5 GALLONS, 3.5 UNUSABLE, 3 GALLONS USABLE). UPON INSPECTING TANKS AT THE INCIDENT SCENE, THE DIPSTICK READ JUST UNDER A 1/4 TANK, BUT ONLY 1 3/8 GALLONS WAS DRAINED AT THE LOW POINT ENG SUMP. (THIS DOESN'T INCLUDE UNUSABLE). BUT IT NEVER MADE IT TO THE ENG IN THE ATTITUDE THE STUDENT PUT THE AIRPLANE INTO. FROM THIS I HAVE LEARNED THAT IF THE QUANTITY IS VERY LOW, LAND IMMEDIATELY. (DO NOT PUSH A FLT TO THE LAST FEW GALLONS). DO NOT TRUST OTHER THAN FACTORY DIPSTICKS. IF POSSIBLE, WHEN TRAINING, FILL THE PLANE TO GROSS WT OR FULL TANKS, WHICH EVER LESS AFTER EVERY LNDG (FOR SECURITY AND STUDENT INEFFICIENCY).

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.