NTSB Factual Report

On June 1, 1997, approximately 0830 central daylight time, a Giertz Vmax Probe experimental aircraft, N1200M, owned and operated by the pilot as a Title 14 CFR Part 91 test flight, was substantially damaged during landing at the Brazoria County Airport, near Lake Jackson, Texas. Visual meteorological conditions prevailed and a flight plan was not filed for the local flight. The private pilot, sole occupant of the airplane, was fatally injured. The flight originated from the Brazoria County Airport, about 5 minutes before the accident.

The 63 year old pilot became qualified as a private pilot on January 9, 1982. According to his pilot log book he had a total flight time of 261.0 hours, and he had logged 8 hours within the last 90 days in a Glasair airplane. There were no biennial flight review entries in the pilot's log book.

The pilot was the owner of Western Composite, where he designed, and built the aircraft. He was conducting the prototype aircraft's initial test flight at the time of the accident and was not wearing a helmet.

The Vmax Probe aircraft is a single place, low wing airplane, with an airframe constructed primarily of composite materials. It was powered by a 808cc, 2-stroke, liquid cooled, 100 HP engine. The canopy and nose exterior skin of the aircraft had to be removed for the pilot to enter or exit.

Witnesses reported to the FAA inspector that the pilot did not complete any high speed taxi tests prior to the accident flight; however, he did do "rudimentary" low speed taxi tests. Witnesses further reported that "immediately" after takeoff from runway 35, it appeared that the "aircraft was being over controlled until it was halfway down the runway." Downwind the pilot reported by radio he had "good control." He also reported that the engine's temperature was 230 degrees Fahrenheit, and he was returning to land.

Witnesses observed the aircraft turning final approach to runway 35 in a "stable" attitude and in a descent. Approximately 5 to 20 feet above the runway, the "aircraft lost directional stability in yaw mode then pitched abruptly toward the ground." The aircraft impacted the runway, "bounced up and went knife edge to the ground." Subsequently, the aircraft impacted the runway about 625 feet from the initial impact point, and slid 625 feet to a stop. The aircraft came to rest inverted approximately 2,535 feet beyond the approach end of the runway and 15 feet left of the centerline.

Examination of the aircraft wreckage by the FAA inspector revealed that the lower vertical fin/rudder and landing gear were separated from the fuselage. The wooden propeller was shattered. The right wing's outboard leading edge was damaged. Further examination of the flight controls revealed "no discontinuity that may have existed prior to the aircraft impacting the ground." A visual examination of the engine did not disclose any mechanical problems that would account for the high operating temperature reported by the pilot.

The pilot restraint system separated at the right hand lap belt attachment point. During the process of preparation for flight tests, the builder/pilot determined that an unacceptable amount of lost motion existed in the flight control system. In order to gain access to the components to be altered, a large section of the structural console on the right hand side of the cockpit was removed. It is through this structure that the right hand lap portion of the pilot restraint system was attached. The original structure was purported to have been calculated as sufficient to meet industry standards for the installation of the restraint system. Subsequent to completion of the alteration of the flight controls a replacement section of console was fabricated to provide closure of the access that was created. That closure consisted of a panel of lesser thickness and markedly different finish than that of the original structure. In addition, this thinner, structural panel was bonded into position over an irregular painted surface of the original console. The right hand lap portion of the pilot restraint system was attached to this replacement panel.

An autopsy was performed at the University of Texas Medical Branch, Galveston, Texas. According to Dr. Soper, Civil Aeromedical Institute, Oklahoma City, Oklahoma, the Atropine and Lidocaine detected in blood and urine were most likely administered during life-saving efforts.

NTSB Probable Cause

The pilot's failure to maintain aircraft control during an approach to landing. A related factor was the pilot's lack of experience in make and model of aircraft.