NTSB Factual Report

HISTORY OF FLIGHT

On August 8, 1999, at 1048 central daylight time, a Stanton Pitts S-1S aerobatic amateur-built experimental airplane, N90HS, was substantially damaged when it impacted tress and terrain while maneuvering near the Red River Airport, Coushatta, Louisiana. The commercial pilot, who was the sole occupant and registered owner of the airplane, was fatally injured. Visual meteorological conditions prevailed and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 personal aerobatic flight. The local flight departed from the Red River Airport approximately 1035.

According to three aerobatic pilot rated witnesses, who were located at the airport at the time of the accident, the pilot was practicing aerobatic maneuvers for an air show. Prior to his second practice run, the pilot told the witnesses that he was going to attempt two consecutive snap rolls prior to landing. The witnesses attempted to talk him out of the idea, stating that he would not have enough altitude or energy to complete the maneuver. The witnesses stated that in the pilot's "normal air show routine," he usually completed one snap roll prior to landing, but not two.

The witnesses stated that after the pilot completed a half Cuban 8, "he pulled the power to idle and then made a left roll to upright, followed by a snap roll to the right." According to the witnesses, during the entry of the second snap roll, "the airplane was low on energy and low in altitude and the airplane entered a nose down spin." They stated that the airplane "made about two turns in the spin prior to impacting the trees in a nose down attitude."

PERSONNEL INFORMATION

The pilot was issued a commercial certificate on March 31, 1998, and a second class medical certificate on April 22, 1999. Review of the pilot's logbooks revealed that he received an aerobatic endorsement on September 8, 1984, and had accomplished an "Acro. Compentency Test" on December 1, 1984, in a Pitts airplane. Friends of the pilot stated that he had stopped flying in 1988, and started flying again in 1997. According to the pilot's logbooks, the pilot had accumulated 405 hours of total flight time, of which 191 hours were in the same make and model as the accident airplane. The pilot had logged 19 flights as "air show" flights.

AIRCRAFT INFORMATION

The single-seat, biplane was issued an experimental airworthiness certificate in 1977. The airplane was powered by a 200-horsepower Lycoming O-360-A4A engine (serial number L-13651-36A). According to the aircraft's mechanic, the amateur-built airplane underwent its last condition inspection on May 1, 1999. The maintenance records were not located during the investigation. Total times on the airframe and engine could not be determined.

METEOROLOGICAL INFORMATION

At 0956, the weather reporting facility at the Shreveport International Airport (located 38 miles northwest of the accident site) reported the wind from 270 degrees at 8 knots, visibility 6 miles with haze, broken clouds at 25,000 feet, temperature 88 degrees Fahrenheit, dewpoint 73 degrees Fahrenheit, and altimeter setting of 30.00 inches of mercury.

WRECKAGE INFORMATION

The airplane came to rest on its nose in a heavily wooded area approximately 1,000 feet southeast of the approach end of runway 35. The top of the airplane was facing a magnetic direction of 204 degrees. The airplane was intact except for the left upper and lower wings, which were adjacent to the wreckage, but were separated at the wing root and twisted so that the leading edge of the upper wing faced the aft end of the airplane, and the leading edge of the lower wing faced forward vertically. Three 40-foot trees, measuring 4 inches in diameter, were freshly cut at the accident site and displayed red paint transfers at the cuts. The tips of the propeller blades were painted with red and white stripes.

All the flight controls were present at the accident site. Control continuity from the cockpit's right rudder pedal to the rudder was confirmed at the accident site. The left rudder cable was disconnected from the left rudder pedal by crash/fire rescue (CFR) personnel. Elevator continuity was confirmed at the accident site. The elevator trim cable was also disconnected by CFR personnel. Continuity of the right upper and lower ailerons was confirmed at the accident site; however, the left aileron control cables were cut by CFR personnel. The left lower aileron was separated from its hinge, and was found on the ground adjacent to the airplane.

The engine and lower fuel tank were displaced aft into the cockpit. When the airplane was moved to one of the airport's hangars for further examination, fuel was found in the upper fuel tank and in the fuel line leading to the carburetor. The carburetor body was broken off of the engine's oil sump. The mixture arm was found broken off of the carburetor, and the throttle valve was found in the closed (idle) position. The magnetos were removed from the engine's accessory section and manually rotated, producing sparks at all distributer cap towers.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy on the pilot was performed at Forensic Pathologists, Inc., in Bossier City, Louisiana. Toxicological tests for carbon monoxide, cyanide, drugs, and alcohol were negative.

ADDITIONAL INFORMATION

The airplane wreckage was released to the owner's representative on August 11, 1999.

NTSB Probable Cause

The pilot's poor in-flight decision to perform aerobatics at a low altitude and slow airspeed, resulting in the inadvertent stall/spin.