Brookeridge Air Park Airport
Aircraft Accident/Incident Report

Downers Grove, Illinois 60516
Friday, September 7, 2001 11:53 CDT

The airplane impacted terrain after striking trees and a power line in a residential area during initial climb from runway 27. Recorded wind data from two weather observation stations reported winds from 170 degrees at 14 knots gusting 17 knots and 200 degrees at 16 knots gusting 22 knots. The pilot used a power setting of 35 inches of manifold pressure and a flap setting of 10 degrees for the takeoff configuration. The only takeoff configurations cited in the pilot's operating handbook and checklists are with the use of 36 inches of manifold pressure and a flap setting of either 0 or 25 degrees. There is no performance data within the pilot's operating handbook for flight configurations using 10 degrees of flaps. A review of the airplane's weight and balance forms found a discrepancy in the empty weight values. The airplane's weight and balance forms were reviewed and Safety Board calculations indicated that the airplane had an empty weight of 2,357.57 pounds and a center of gravity of 79.9 inches, compared to an empty weight of 2,261.67 pounds and a CG of 83.3 inches listed in the latest revision forms. The pilot reported using a basic empty weight of 2,304 pounds and a CG of 83.3 inches in his weight and balance calculations. The Safety Board calculated the weight and CG location for the accident flight as 3,490 pounds and 87 inches, respectively. The forward CG range for the accident airplane's weight was between 89 inches and 95 inches. Information about the effects of CG location and wind velocity on takeoff performance is available to pilots from the Federal Aviation Administration and commercial publications. Postaccident examination of the engine found evidence of some spark plug fouling, and camshaft and lifter body wear, although the negative effect of this wear on engine performance is not known because the proper short field takeoff procedures were not followed. The airplane's engine logs did not specify whether oil filters were inspected for metal debris during oil and filter changes.

the improper preflight planning/preparation and the short field take off/procedure not followed by the pilot. Contributing factors were the airplane's forward center of gravity, the variable gusting wind and improper weight and balance calculations by maintenance personnel.