Slaton, TX, USA
N765MM
Akers Douglas RA40 Defiant
The one-piece canopy opened to a near-vertical position during the initial takeoff climb. The 2,300-hour pilot reduced engine power and the airplane descended back towards the runway. Seconds later engine power was restored and the airplane was observed climbing. As the airplane was climbing, the canopy was observed "bobbing" up and down. The pilot then initiated an approximate 315-degree descending left turn. After rolling out, the airplane started banking back and forth and pitching up and down rapidly before settling in a nose down attitude. Subsequently, the airplane impacted the ground.
On December 17, 2004, about 1340 central standard time, an Akers Douglas RA40 Defiant, inline twin-engine experimental airplane, N765MM, was destroyed when it impacted the ground, following a loss of control during takeoff initial climb from the Slaton Municipal Airport (F49), near Slaton, Texas. The instrument rated private pilot, sole occupant of the airplane, sustained fatal injuries. The airplane was registered to and operated by the pilot. Visual meteorological conditions prevailed and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 personal flight. An investigator from the National Transportation Safety Board, a representative from the Federal Aviation Administration, and local law enforcement officials interviewed five eyewitnesses. Summaries of their observations are cited below. Witnesses #1 and #2 were standing at the edge of the taxiway east of the ramp when they first observed the airplane at the south end of the runway about to start its takeoff roll. As the airplane accelerated down runway 36, witness #2 took several pictures of the departing airplane. The witnesses reported that shortly after takeoff they observed the canopy "pop open." The witnesses then heard a reduction in noise from the engines and observed the airplane descend back towards the runway. Seconds later, they heard the noise from the engines increase as the airplane resumed climbing. Witness #1 further reported that as the airplane was climbing, she could see the canopy "bobbing" up and down, and approximately 700 feet above ground level (agl), it appeared that the canopy departed the airplane. A review of the photos taken by witness #2 revealed that the canopy was in an open position while the airplane was approximately 25 feet agl. Witness #3 was standing at the self-service fuel pumps, abeam runway 36 near the halfway point, when he observed the airplane taxi to the south end of the runway for a north departure. The witness reported that just after the airplane departed the runway, the canopy opened to a near-vertical position. He then heard the engine noise reduce for a brief moment, then increase, and shortly thereafter saw the canopy go towards the closed position. Witness #4 was standing on the ramp when he observed the airplane "wallowing" in the air. The witness reported that when the airplane was approximately 500-700 agl, he saw a flash of light come from the airplane. Several minutes later, when he again returned his attention to the airplane, it was in a nose down attitude and disappeared from view into a canyon that is located north of the airport. Witness #5 was welding on a fence approximately one mile north of the airport. The witness reported that he first noticed the airplane shortly after it had taken off from the airport. As the airplane passed overhead in a northerly direction, he observed papers coming out of the cockpit. The witness then observed the airplane initiate an approximate 315-degree descending left turn. After rolling out on a northeast heading, the airplane started banking back and forth and pitching up and down rapidly before finally settling in a nose down attitude. The airplane remained in this attitude until it contacted the ground. The witness further reported that he did not see anything other than papers fall from the airplane. An inspector from the Federal Aviation Administration performed an onsite examination of the wreckage. The inspector reported that all major components of the airplane, including the canopy, were accounted for at the wreckage site. The inspector further reported that the airplane had been destroyed during a post impact fire. The pilot held a FAA private pilot certificate with ratings for single-engine land, multi-engine land, and instrument airplane. At the time of his last third-class FAA medical certificate, issued on December 15, 2004, the pilot reported his total flight time as 2,300 hours, with 60 hours in the preceding six months. The pilot's personal logbooks were not available for review during the course of the accident investigation. The composite airplane was a four seat experimental RA40 Defiant, serial number 162. The airplane was powered by two Textron Lycoming O-320 four-cylinder reciprocating engines. The propellers were of composite construction. The canopy was a one-piece design that covered all four seats. It was attached by a piano hinge along the right side of the cabin, and pivoted to the right side when open. The control stick was located on the left side of the cockpit. The airplane's logbooks were not available for review during the course of the investigation; therefore, the airframe and engine time, and the date and type of the last inspection could not be determined. According to the Defiant owners manual, first edition, dated May 1988, the "canopy opening in flight is a serious emergency." The manual further states the following: "With the canopy unlatch warning and the safety catch, the likelihood of a canopy opening in flight is remote. However, should the canopy open to the safety latch, the aircraft is still controllable. Reduce airspeed to minimize windblast and return and land. Should the canopy come fully open in flight it will probably come off and take the rear prop with it. You will be faced with air blast and a single engine airplane with high drag. The performance or flying qualities of this configuration have not been tested. Remember to maintain aircraft control. Do not be so concerned with closing the canopy that you allow the aircraft to fly unnecessarily into the ground. A low speed of 70 to 75 knots is recommended for canopy-off failure condition." Fueling records obtained from a local fixed-base operator revealed that the airplane was last fueled on December 17, 2004, with 30.18 gallons of 100 Low Lead aviation fuel. The Lubbock County Medical Examiner performed an autopsy on December 18, 2004. The FAA Toxicology and Accident Research Laboratory in Oklahoma City, Oklahoma, performed toxicological testing of specimens of the pilot. The results of analysis were negative for volatiles and tested drugs. The report contained the following positive results: 20 percent carbon monoxide and 1.7 (ug/ml) cyanide detected in blood. At 1353, the automated weather observing system at Lubbock International Airport (LBB), near Lubbock, Texas, located approximately 13.4 miles northwest of the accident site, reported wind from 240 degrees at 12 knots, visibility 10 statute miles, sky clear, temperature 54 degrees Fahrenheit, dew point 23 degrees Fahrenheit, and a barometric pressure setting of 30.29 inches of Mercury.
The pilot's failure to maintain aircraft control. Contributing factors were the opening of the canopy in-flight and the pilot's diverted attention.
Source: NTSB Aviation Accident Database
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