Narrative:

The aircraft in question; an rv-6A (nosewheel); was built over a period of years by a very inexperienced pilot. The builder took a few hours dual in an rv-6 (conventional gear) but had and has no experience in an rv-6A and his dual time in the rv-6 was several months in the past. The rv-6A was complete and I agreed to assist the builder in 'debugging' the airplane. To this end I did an extensive inspection of the airplane and identified an issue with the brakes. After the builder fixed the brakes we fast taxied the airplane several times and identified an issue with the nav/com and a possible issue with the alternator. The nav/com issue was resolved and the builder attempted to fast taxi the airplane on his own on at least one occasion but had problems with directional control using the rudder only and directional control while braking. We planned to fast taxi the airplane once more. The owner did so with me in the right seat; almost lifted off; and I closed the throttle to prevent takeoff. I suggested we repeat the exercise with both of us on the controls. We did so. The wind was from 090 at 8; variable and gusting. We accelerated to the point where the nosewheel could be lifted and reduced power somewhat to prevent liftoff but caught a gust or roll turbulence off the terrain to our right. Long story short the airplane lifted off to at least 20 feet and drifted left. We were low; slow; with the nose pitched up at somewhat reduced power; close to a stall. In my judgment there was too little runway left to close the throttle and land without running off the end of the runway and hitting an obstacle. I made the decision under what I felt was an emergency to fly the airplane around the pattern and land; which I did. Since I had not planned to fly the airplane I did not review the operating limitations issued with the airworthiness certificate but most homebuilt aircraft are limited to one person for the first 25 or 40 hours thus we may have violated the operating limitations of the airplane. It should be noted that this was a first flight for this airplane and the single circuit around the pattern and landing were uneventful; although it did appear the oil pressure at flight power was too high and needs to be adjusted. That said had I intended that the airplane fly I would have read the operating limitations; flown the airplane solo if the operating limitations so required (there is no way the builder is competent to fly this airplane solo); worn a nomex flight suit and gloves; a crash helmet; had a crash truck standing by and so on; all the usual preparations one makes and precautions one takes before the first flight of a homebuilt airplane. What did I learn: 1) in the future I will avoid doing this type of taxi training/debugging anytime there is a crosswind and/or a gusting wind; 2) in the future I will keep one hand on the throttle as well as the stick and rudder to better control speed; particularly in an airplane with a high a power to weight ratio such as the rv-6A which accelerates quickly; and 3) in the future I will better brief the trainee to prevent inadvertent takeoff. We were fortunate that the builder did a good job and no major problems occurred in this unplanned flight.

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Original NASA ASRS Text

Title: An RV-6A Flight Instructor reported taking off from an intended fast taxi test when a gust of wind forced the aircraft airborne.

Narrative: The aircraft in question; an RV-6A (nosewheel); was built over a period of years by a very inexperienced pilot. The builder took a few hours dual in an RV-6 (conventional gear) but had and has no experience in an RV-6A and his dual time in the RV-6 was several months in the past. The RV-6A was complete and I agreed to assist the builder in 'debugging' the airplane. To this end I did an extensive inspection of the airplane and identified an issue with the brakes. After the builder fixed the brakes we fast taxied the airplane several times and identified an issue with the nav/com and a possible issue with the alternator. The nav/com issue was resolved and the builder attempted to fast taxi the airplane on his own on at least one occasion but had problems with directional control using the rudder only and directional control while braking. We planned to fast taxi the airplane once more. The owner did so with me in the right seat; almost lifted off; and I closed the throttle to prevent takeoff. I suggested we repeat the exercise with both of us on the controls. We did so. The wind was from 090 at 8; variable and gusting. We accelerated to the point where the nosewheel could be lifted and reduced power somewhat to prevent liftoff but caught a gust or roll turbulence off the terrain to our right. Long story short the airplane lifted off to at least 20 feet and drifted left. We were low; slow; with the nose pitched up at somewhat reduced power; close to a stall. In my judgment there was too little runway left to close the throttle and land without running off the end of the runway and hitting an obstacle. I made the decision under what I felt was an emergency to fly the airplane around the pattern and land; which I did. Since I had not planned to fly the airplane I did not review the operating limitations issued with the airworthiness certificate but most homebuilt aircraft are limited to one person for the first 25 or 40 hours thus we may have violated the operating limitations of the airplane. It should be noted that this was a first flight for this airplane and the single circuit around the pattern and landing were uneventful; although it did appear the oil pressure at flight power was too high and needs to be adjusted. That said had I intended that the airplane fly I would have read the operating limitations; flown the airplane solo if the operating limitations so required (there is no way the builder is competent to fly this airplane solo); worn a Nomex flight suit and gloves; a crash helmet; had a crash truck standing by and so on; all the usual preparations one makes and precautions one takes before the first flight of a homebuilt airplane. What did I learn: 1) In the future I will avoid doing this type of taxi training/debugging anytime there is a crosswind and/or a gusting wind; 2) In the future I will keep one hand on the throttle as well as the stick and rudder to better control speed; particularly in an airplane with a high a power to weight ratio such as the RV-6A which accelerates quickly; and 3) In the future I will better brief the trainee to prevent inadvertent takeoff. We were fortunate that the builder did a good job and no major problems occurred in this unplanned flight.

Data retrieved from NASA's ASRS site as of April 2012 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.