CHI94LA318

The pilot reported that he attempted to takeoff at a private field on an 1,800 foot long runway. The runway surface consisted of wet grass about six inches tall. He said he calculated the takeoff distance on a grass runway to be 880 feet. About three fourths of the way down the runway, the pilot felt the airplane was not going to become airborne. He aborted the takeoff and the airplane departed the end of the runway, sustaining substantial damage.

On September 8, 1994, about 2240 eastern daylight time, a Piper PA-38-112 airplane, N4286E, sustained substantial damage when it departed the runway during an aborted takeoff from the Thompson Airport, West Branch, Michigan. The private pilot and one passenger reported no injuries. The 14 CFR Part 91 flight was planned to Mason, Michigan, in visual meteorological conditions. No flight plan was filed.

The pilot reported the runway surface was wet grass about six inches tall. He calculated the takeoff distance to be 800 feet for a dry, paved runway then added 10 percent due to the grass runway. He said he used short, soft field takeoff procedures during the attempt to depart the 1,800 foot long runway. When the airplane reached a speed of 55 knots he lowered the flaps and rotated but the airplane did not become airborne. About three-fourths of the way down the runway he elected to abort the takeoff. He shut down the engine, applied wheel brakes, and steered around trees. The nose wheel caught in a shallow ditch and a wing impacted the ground. The airplane sustained substantial damage to the firewall, wings, and fuselage.

The PA-38-112 pilot's operating handbook (POH) contains takeoff performance graphs for a "paved level dry runway" with zero and one notch wing flaps. The POH warns that "performance information derived by extrapolation beyond the limits shown on the charts should not be used for flight planning purposes." The normal takeoff section specifies "normally, flaps are left up for takeoffs; however for short field takeoffs and for takeoffs under such conditions as deep grass or a soft surface, total distances can be reduced appreciably by lowering the flaps one notch and rotating at a lower airspeed." No performance data is provided for these conditions.