CHI04LA279

The experimental amateur-built aerobatic airplane was substantially damaged when it impacted trees and terrain during an aerobatic maneuver. The pilot reported that they entered a hammerhead [stall maneuver] at 140 - 145 [miles per hour]. The pilot-rated passenger reported that the pilot executed a "sporty" takeoff, followed by a vertical climb. He stated the pilot performed a hammerhead stall and a low-level pass down the runway. The pilot-rated passenger stated that near the end of the runway the pilot once again pulled into a vertical climb, followed by another hammerhead stall. He reported that as the pilot applied power entering the climb the engine hesitated momentarily similar to when the throttle is advanced too quickly. The passenger stated that the aircraft did not have enough altitude to regain airspeed after the stall. Witnesses stated that the accident airplane took off and pulled into a vertical climb. The pilot executed several aerobatic maneuvers including low-level passes over the runway. The witnesses thought the airplane had departed the area when they saw it descend into trees south of the airport. The airport manager, one of the witnesses, stated that the airplane impacted at a 60-degree or more angle and recalled that it was not spinning or turning. The witnesses did not perceive any engine problems. The aircraft impacted a one-lane airport perimeter road south-southeast of the runway. Trees, approximately 25 feet in height, lined both sides of the road. Numerous tree strikes were observed on the tree line south of the road. The aircraft came to rest on the north side of the road, oriented in a southerly direction. A post-accident examination did not reveal any anomalies associated with a pre-impact failure. The operation manual for the accident aircraft stated that the recommended entry speed for a hammerhead stall maneuver was between 130 and 180 miles per hour.

On September 25, 2004, about 1700 eastern standard time, an experimental amateur-built Ernst Pitts S2E airplane, N8005X, piloted by a private pilot, was substantially damaged during an in-flight collision with trees and terrain near Lee Bottom Airport (64I), Hanover, Indiana. The flight was being conducted under 14 CFR Part 91 without a flight plan. Visual meteorological conditions prevailed. The pilot and pilot-rated passenger sustained serious injuries. The flight departed 64I about 1645 with an intended destination of Moraine Airpark (I73), Dayton, Ohio.

In his written statement, the pilot reported: "For a few hours I had been extremely thirsty. There was only a soda machine, so I had one. I think we entered a hammerhead [stall maneuver] at 140 - 145 [miles per hour]. I believe dehydration contributed to this error."

The pilot-rated passenger reported that the pilot executed a "sporty" takeoff, establishing a shallow climb angle in order to build speed after liftoff. He noted that near the departure end of the runway, the accident pilot pulled into a vertical climb and applied full power. He stated that the pilot performed a hammerhead stall at the top of the climb, followed by a low-level pass over the runway.

The pilot-rated passenger stated that near the end of the runway the pilot once again pulled into a vertical climb, followed by another hammerhead stall. He reported that as the pilot applied power entering the climb the engine hesitated momentarily similar to when the throttle is advanced too quickly. The passenger stated that the aircraft did not have enough altitude to regain airspeed after the stall. The passenger commented that the pilot was "very proficient" in aerobatics.

The airport manager stated that after takeoff the pilot executed torque rolls while in a vertical climb. He noted the pilot then entered a split-S, followed by a hammerhead stall. He recalled that the pilot subsequently executed an inverted pass over the runway about 20 feet above ground level (agl). The pilot finished with an outside loop and it appeared to him that the aircraft had departed the area.

The airport manager stated that a minute or two later someone pointed out the aircraft. When he looked up, he saw it go straight down behind a line of trees south of the airport. He noted that the airplane impacted at a 60-degree or more angle relative to the horizon and recalled that it was not spinning or turning. He commented that he did not perceive any engine problems.

A second witness reported that when the accident aircraft took off, it pulled up and entered a hammerhead stall. He stated the pilot executed an inverted pass down the runway about 25 feet agl. The aircraft then entered another "vertical maneuver" and returned for a second inverted pass. He recalled seeing something fall into the canopy during one of the inverted passes.

This witness reported that the aircraft turned as though it was departing the area. However, shortly afterward someone noticed the aircraft again. He stated that he looked up and saw the aircraft off the end of the runway. He reported that "it went straight in." He noted he "didn't hear the engine sputter or misfire" during the time he observed the aircraft.

The aircraft impacted a one-lane airport perimeter road south-southeast of the runway. Trees, approximately 25 feet in height, lined both sides of the road. Numerous tree strikes were observed on the tree line south of the road. The aircraft came to rest on the north side of the road, oriented in a southerly direction.

The airport manager recalled weather conditions as good, with high broken clouds, calm winds and "excellent" visibility.

A post-accident inspection did not reveal any anomalies associated with a pre-impact failure. The elevator and rudder remained attached. Control continuity was traced from the elevator and rudder to the cockpit area. The ailerons were damaged but remained attached to the airframe. Aileron control continuity was not determined due to wing damage.

FAA records indicate that the pilot bought the accident aircraft on April 29, 2004. The FAA issued an experimental airworthiness certificate for the aircraft on January 4, 1991. The maintenance logbooks indicated the total airframe time was 259.8 hours, with 106.3 hours since inspection. The most recent conditional inspection was on March 1, 2004.

According to his logbook, the accident pilot had logged 637 hours total flight time, with 215 hours flight time in Pitts aircraft. He had logged 17 hours within the 30 days prior to the accident. All of that flight time was in the accident aircraft.

The operation manual for the accident aircraft stated that the recommended entry speed for a hammerhead stall maneuver was between 130 and 180 miles per hour.