NTSB Factual Report

HISTORY OF FLIGHT

On August 23, 2000, at 0207 central daylight time, a Cessna 340A, N34DD, was destroyed on impact with terrain and fire following departure from the Mission Sioux Airport (0V6), Mission, South Dakota. Night visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 business flight was not operating on a flight plan. The commercial pilot and two passengers were fatally injured. The flight was originating at the time of the accident and was en route to the Rapid City Regional Airport (RAP), Rapid City, South Dakota.

A line attendant and refueler reported to the Federal Aviation Administration that early in the morning of August 22, 2000, N34DD left for Mission, South Dakota, with the pilot at the controls. The main fuel tanks were full before the airplane left. The airplane returned from Mission at 1645 (Rapid City, South Dakota, is in the mountain time zone). Shortly thereafter, the airplane was serviced with 34.2 gallons of fuel in the main tanks, topping them off. He further stated the aircraft was about to be put away for the night when the pilot called him and said he was going back out on another trip to Mission. He said [the pilot] wanted him to put 10 gallons in each auxiliary fuel tank. He stated that he was only able to service the auxiliary fuel tanks with a total of 18.5 gallons of fuel. The pilot and two passengers departed Rapid City at approximately 1930. The two main fuel tanks and two auxiliary fuel tanks were full of fuel before the airplane left on its last flight.

A witness reported, "A/C departed Mission and started making bank to turn (u turn) then after coming out of its bank the a/c started to lose altitude. It looked like the A/C was about 50 ft. above the top of the big ridge. A/C was level, I saw sparks from the left engine - then heard a bang like a shotgun. Then the aircraft banked to left and went down out of sight. Then at about this time I heard the muffled sound of the crash (like crunching) then I saw the fire ball + smoke. Then I went to the University + told my brother ... to call police - ambulance - + fire trucks. I went to the crash site. Upon arrival I parked the pickup on top of the ridge + ran to the plane. I hollered out - no response..."

A second witness reported, "I saw an airplane leaving Antelope Airport. I saw the airplane travel around or near 2 to 3 miles northeast of Mission, SD. I heard the airplane sputter like something was wrong with the choke. Airplane dropped downwards. I heard a surge of power again in the engines. 2 or 5 seconds later I saw the airplane drop downwards. I saw a cloud of smoke and heard a loud pounding noise. I saw fire coming from where the airplane went down..."

A third witness reported, "We were parked on a dirt road standing outside my vehicle and noticed that a plane was taking off, the plane sounded like it was sputtering after it took off then it sounded like it was accelerating then I heard a loud bomb then seen a large ball of fire."

PERSONNEL INFORMATION

The pilot was 57 years old and employed as a pilot by the registered aircraft owner. He held a commercial pilot certificate with airplane single engine land, multiengine land and instrument airplane ratings. At the application of the pilot's second-class medical certificate on March 21, 2000, a total flight time of 900 hours was reported. The medical certificate had the restriction, "must wear corr lenses & possess glasses for near & intrm vision". A total flight time of 1,022 hours of which 24 hours in this make and model was reported in the National Transportation Safety Board's (NTSB) 6120.1/2 form (pilot/operator aircraft accident report). The pilot completed a Cessna 340A initial training course on August 11, 2000.

AIRCRAFT INFORMATION

The Cessna 340A, serial number 340A0308, was purchased on July 24, 2000, by the registered owner. The airplane was modified through a RAM series VI conversion with the installation of vortex generators and an increase in the horsepower rating of the engines. According to logbook entries dated July 24, 2000, the airplane received an annual inspection at a total airframe time of 3,819 hours. The airplane was powered by two Continental TSIO-520-KCNB engines with the right engine being serial number R-504286 and the left engine being serial number L-228274 installed on November 26, 1996. According to logbook entries dated July 24, 2000, both engines received a 100-hour inspection at 646 hours since their major overhaul and at a total engine time of 1,655 hours.

Airworthiness Directive (AD) 75-23-08, revision 05, pertains to the inspection and parts replacement of the engine exhaust system. AD 75-23-08 was superceded by AD 2000-01-16, which pertains to the detection and correction of cracks and corrosion in the exhaust system. The airplane's AD compliance record indicates that AD 2000-01-16, paragraphs b, c, d, e, and f was recorded as complied with on July 24, 2000 at a Hobb's time of 3,819 hours.

METEOROLOGICAL INFORMATION

The Miller Field Airport, Valentine, Nebraska, automated surface observing system recorded at 0152, wind from 070 degrees at 3 knots, 8 sm visibility, clear sky conditions, temperature of 19 degrees C, dew point of 18 degrees C and an altimeter setting of 30.07 inches.

The RAP automated surface observing system recorded at 0155, wind from 300 degrees at 4 knots, 10 sm visibility, clear sky conditions, temperature of 18 degrees C, dew point of 14 degrees C and an altimeter setting of 30.10 inches.

The U.S. Naval Observatory reported that at 2400 central standard time, the fraction of the moon illuminated was 0.45.

WRECKAGE AND IMPACT INFORMATION

The wreckage path extended for a length of approximately 230 feet along a magnetic heading of 290 degrees. The airframe was 186 feet from eastern edge of the wreckage path and oriented on a tail to nose magnetic heading of 160 degrees. The GPS location of the airframe was 43 degrees 19.52 minutes north, 100 degrees 36.63 minutes west at an elevation of 2,688 feet msl. The eastern 37 feet of ground scarring contained a propeller spinner, propeller dome and a landing gear mirror. Forty-seven feet from the ground scar's eastern edge, three 3-foot parallel curvilinear marks were noted. Each curvilinear mark was separated from each other by one foot and was 5 inches, 10 inches and 12 inches in depth. The increase in depth proceeded the east to west. Both engines were separated from the airframe. Both propellers were separated from the engines and exhibited bending and twisting.

The flight control cables were traced from the elevator and rudder to the control column. The right aileron control cable was traced to the cabin area. The left aileron control cable was traced from the center of the cabin area to the main spar attach point.

The rudder trim actuator was extended 1-1/4 inches, which was equivalent to a position beyond the right limit of travel. The elevator trim actuator was extended 1-1/4 inches or an equivalent 10 degrees tab down.

There was a four-link extension of the chain leading from the control cable to the number one sprocket of the flap-actuating wheel. The extension was equivalent to a retracted flap position.

Both main landing gears were in a retracted position.

Both engine fire-extinguishing bottles located along the debris path indicated a pressure of approximately 500 psi.

MEDICAL AND PATHOLOGICAL INFORMATION

The Clinical Laboratory of the Black Hills, Rapid City, South Dakota, conducted an autopsy of the pilot.

Federal Aviation Administration (FAA) toxicological test results indicated the presence of 11 (mg/dL, mg/hg) ethanol in kidney, 3 (mg/dL, mg/hg) acetaldehyde in kidney, 0.343 (ug/ml, ug/g) diphenhyramine in kidney and 2.991 (ug/ml, ug/g) diphenhydramine in liver.

In its investigations, the NTSB routinely requests complete toxicology evaluation on all transportation operators who are fatally injured. In around 10% of such evaluations, ethanol is detected in the blood and/or tissues. In many of these cases, particularly when significant decomposition has taken place, the ethanol present is the result of production of alcohol by microorganisms in the tissues after death, and does not represent the ingestion of alcohol. When vitreous fluid and/or urine (substances which do not normally support the postmortem production of alcohol) are available for testing, it may be possible to determine conclusively whether the ethanol present was a result of postmortem production of alcohol or ingestion of alcohol. Vitreous fluid and urine typically cannot be obtained from bodies in relatively advanced stages of decomposition, and a conclusive determination regarding the source of ethanol in such bodies is difficult or impossible.

When laboratory evaluation cannot conclusively determine whether the ethanol found is the result of post-mortem production, NTSB investigators will review all the available information regarding the accident so that the Safety Board can determine whether ethanol resulted from post-mortem production or ingestion. Factors that are considered include (but are not limited to): extent of putrefaction (decay) of the specimens, time since death, temperature of the surroundings, immersion, levels of ethanol found, distribution of ethanol in tissues, and any evidence suggesting or eliminating the possibility of alcohol ingestion prior to or during vehicle operation. An article reviewing the experience of the FAA Civil Aeromedical Institute Toxicology and Accident Research Laboratory with postmortem alcohol production in fatal aircraft accidents was published in 1993 (Canfield DV, Kupiec T, Huffine E. 1993. Postmortem Alcohol Production in Fatal Aircraft Accidents. Journal of Forensic Sciences 38:4, 914-917. [July]).

Diphenhydramine (commonly known by the trade name Benadryl) is an over-the-counter antihistamine with sedative effects, often used to treat allergy symptoms. In normal doses, the medication commonly results in drowsiness, and has measurable effects on performance of complex cognitive and motor tasks (e.g. flying an aircraft). Reduced performance has been demonstrated even in individuals who feel normal after ingesting the drug (see, for example, Weiler et. Al. Effects of Fexofenadine, Diphenhydramine, and Alcohol on Driving Performance. Annals of Internal Medicine 2000; 132:354-363, in which the effect of a normal dose of diphenhydramine is noted to be worse than the effect of a 0.10% blood alcohol level).

COMMUNICATIONS

A summary of communications with the Huron Flight Service Station were reported relative to mountain daylight time (mdt) as follows:

0414 mdt Weather brief RAP to Mission (0V6) - marginal VFR 0556 mdt Filed VFR direct 0V6, 35-minute en route... 0620 mdt Activated flight plan 0713 mdt Cancelled flight plan at 0V6 1128 mdt Weather brief Mission to RAP - marginal VFR 1448 mdt Filed VFR Mission to RAP, N34DD departing in 30-45 minutes... 1617 mdt Activated flight plan 1703 mdt Cancelled flight plan (N34DD reported being on the ground in Rapid City)

AIRPORT INFORMATION

0V6 is an uncontrolled airport served by runway 11-29 (3,200 feet by 60 feet, asphalt) with a field elevation of 2,605 feet msl. The airport is equipped pilot controlled low intensity runway lighting. The coordinates of 0V6 are 43 degrees 18.42 minutes north, 100 degrees 37.69 minutes west.

The coordinates of RAP are 044 degrees 02.72 minutes north, 103 degrees 03.44 minutes west.

TESTS AND RESEARCH

Both engines were shipped to Teledyne Continental Motors (TCM) for examination. The TCM analytical reports for the left and right engines both stated, "This engine exhibited normal operational signatures throughout. All internal components appeared well lubricated. The engine did not exhibit any condition that would have caused an operational problem." These TCM analytical reports are included in this report.

Both turbochargers were shipped to Honeywell for the examination. The teardown report stated, "(a) The left turbocharger was rotating on impact. No pre-accident conditions were identified which would have interfered with normal operation of the left turbocharger. (b) The right turbocharger was rotating at impact. Pending the results of a NTSB metallurgical analysis of the right turbocharger turbine-housing flange, no pre-accident conditions were identified which would have interfered with normal operation of the right turbocharger." The report is included in this report.

The right engine turbocharger housing and exhaust pipe assembly fractures were examined by the NTSB's Material Laboratory Division. A photo of the right turbocharger/exhaust area is included in this report. The Materials Laboratory Factual Report is included in this report.

ADDITIONAL INFORMATION

The FAA, Cessna Aircraft Company and TCM were parties to the investigation.

The wreckage and related parts, which underwent examination, were released to registered owner's insurance representative.

NTSB Probable Cause

the aircraft control not maintained by the pilot. A contributing factor was pilot fatigue.