Narrative:

New aircraft owner flying with instructor to meet 5 hours in type for insurance purposes. At the end of the third hour, pilot attempted to land on grass runway with right quartering headwind to crosswind. Pilot had series of bounces on landing. Instructor took control to stop bouncing but was unable to keep aircraft from nosing over onto the propeller at about 20 mph. In the latter part of the landing roll, the aircraft appeared to have attained a steady 3 point (tail down) attitude but, as it came abeam a line of hangars, the tail lifted up as in slow motion and nosed over. I believe, in hindsight, a go around by the pilot would have prevented this incident. The instructor was attempting to demonstrate that, if the pilot held full aft yoke without flying airspeed, the aircraft would not bounce. Unfortunately, it appears that there must have been a venturi effect on the wind around the hangars which shifted the wind to a tailwind which raised the tail as we came abeam them.

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Original NASA ASRS Text

Title: AN INSTRUCTOR PLT RPTS THAT HE ALLOWED A C180 TO NOSE OVER WHEN LNDG ON GRASS. WX FACTORS, THERE MAY HAVE BEEN A WIND SHIFT FROM AROUND SOME HANGARS THAT COULD HAVE LIFTED THE TAIL. ERROR ADMITTED, THEY SHOULD HAVE MADE A GAR.

Narrative: NEW ACFT OWNER FLYING WITH INSTRUCTOR TO MEET 5 HRS IN TYPE FOR INSURANCE PURPOSES. AT THE END OF THE THIRD HR, PLT ATTEMPTED TO LAND ON GRASS RWY WITH R QUARTERING HEADWIND TO XWIND. PLT HAD SERIES OF BOUNCES ON LNDG. INSTRUCTOR TOOK CTL TO STOP BOUNCING BUT WAS UNABLE TO KEEP ACFT FROM NOSING OVER ONTO THE PROP AT ABOUT 20 MPH. IN THE LATTER PART OF THE LNDG ROLL, THE ACFT APPEARED TO HAVE ATTAINED A STEADY 3 POINT (TAIL DOWN) ATTITUDE BUT, AS IT CAME ABEAM A LINE OF HANGARS, THE TAIL LIFTED UP AS IN SLOW MOTION AND NOSED OVER. I BELIEVE, IN HINDSIGHT, A GAR BY THE PLT WOULD HAVE PREVENTED THIS INCIDENT. THE INSTRUCTOR WAS ATTEMPTING TO DEMONSTRATE THAT, IF THE PLT HELD FULL AFT YOKE WITHOUT FLYING AIRSPD, THE ACFT WOULD NOT BOUNCE. UNFORTUNATELY, IT APPEARS THAT THERE MUST HAVE BEEN A VENTURI EFFECT ON THE WIND AROUND THE HANGARS WHICH SHIFTED THE WIND TO A TAILWIND WHICH RAISED THE TAIL AS WE CAME ABEAM THEM.

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.