Aviation Accident Summaries

Aviation Accident Summary SEA98FA088

PRINDLE, WA, USA

Aircraft #1

N6234D

Cessna 172N

Analysis

The non-instrument rated pilot took off at 0211 under dark night conditions and encountered ceilings of 1,400 foot broken and 2,200 foot overcast. The radar track showed the aircraft reaching an altitude of 2,000 feet as it entered into a left, descending spiral. The last radar target was within 1/2 mile of the crash site and the distribution of wreckage and tree strikes indicated a steep descent angle. Toxicological test revealed the pilot had blood levels of 0.020 (ug/ml, ug/g) amphetamine, 0.092 (ug/ml, ug/g) methamphetamine, and 0.005 (ug/ml, ug/g) tetrahydrocannabinol (the active substance in marijuana).

Factual Information

HISTORY OF FLIGHT On June 4, 1998, at 0223 Pacific daylight time, a Cessna 172N, N6234D, registered to and being flown by a private pilot, was destroyed following an in-flight loss of control and subsequent uncontrolled descent and collision into terrain approximately 11 minutes after takeoff from the Troutdale airport, Troutdale, Oregon. The pilot and two passengers sustained fatal injuries. There was no fire. Variable meteorological dark night conditions existed at the time, and no flight plan had been activated. The flight, which was personal, was to have been operated under 14CFR91, and was destined for Hermiston, Oregon. There were no known witnesses who saw the aircraft depart the Troutdale airport, and the airport's air traffic control tower was closed at the time. There were no eye-witnesses to the accident, however, an ear-witness, who was located near the accident site reported that "approx(imately) 2:00 to 2:15 this morning I heard the sound of a small plane winding out at a distance. I heard the sound twice within a matter of seconds - the second sound was followed by the sound of an impact. It sounded to me as if the sounds came from a southerly direction from my home" (refer to ATTACHMENT S-I). Radar data from the Seattle Air Route Traffic Control Center (ARTCC) recorded a code 1200 mode "C" transponder target at 0212:39 at 800 feet above mean sea level (MSL) less than a mile southwest of the Troutdale airport. A series of targets were recorded progressing (in time) northeast to the Columbia River and then along the river to the east tip of Reed Island. The track of targets then progressed in an elliptical 360 degree left turn before returning over the river. The targets were then observed to track along the south shore of the river for approximately five miles and then progress into a second elliptical 360 degree left turn with the last recorded target (0222:16) located approximately one-half mile east of the ground impact site (refer to CHARTS I and II). The aircraft's altitude during this track varied from a minimum of 800 feet MSL (first target nearest Troutdale airport, elevation 35 feet MSL) to a maximum of 2,000 feet MSL (late target). Rapid changes of altitude were noted during the mid points of both elliptical turns (refer to TABLE I). PERSONNEL INFORMATION The pilot's first and only FAA medical examination was conducted on October 19, 1995. At that time the pilot reported "0" hours flight experience. He was issued his private pilot's certificate on February 27, 1996. The pilot did not possess an instrument rating. No pilot logs were found at the aircraft site. A request for the pilot's flight log was made to the representative of the estate of the pilot through her attorney. However, the logs were not provided. AIRCRAFT INFORMATION No aircraft logs or records were found at the aircraft site. As with the pilot's log, a request for the logs was made to the representative of the estate of the pilot through her attorney. However, the aircraft logs were not provided. FAA records showed the aircraft being registered to the pilot on June 13, 1996. The aircraft's tachometer was found at the accident site. The RPM needle was missing, however, the hour meter was readable. The digital wheels on the hour meter were observed to read either 6170.9 hours or 7270.9 hours (refer to Supplement B, page 1). METEOROLOGICAL INFORMATION The surface weather observation taken at Portland International airport, located 15 nautical miles west southwest of the accident site (9 nautical miles west of the Troutdale airport) reported the following conditions at 0156 hours on the morning of the accident: Ceiling: 1,400 foot broken, 2,200 foot overcast Visibility: 10 miles Winds: 300 degrees magnetic at 8 knots Temperature: 13 degrees C. Dew Point: 12 degrees C. Additionally, a witness located near the accident site reported that between 0200 and 0215 he "went outside to see if I could hear or see anything but it was foggy" (refer to ATTACHMENT S-I). A pilot using aircraft call sign "N6234D" contacted the McMinnville Automated Flight Service Station (AFSS) at 2014 hours "requesting a preflight briefing for a flight from Hermiston, Oregon, to Troutdale, Oregon," on June 3rd. The AFSS technician reported that "He is provided with a standard weather briefing, and files a flight plan" (refer to ATTACHMENT AFSS-I). There was no record of a weather briefing or flight plan for the flight departing Troutdale at 0212 hours. WRECKAGE AND IMPACT INFORMATION The aircraft crashed in heavily wooded terrain approximately two nautical miles west of Prindle, Washington. The accident site coordinates were determined using a hand held GPS unit and were found to be 45 degrees 35.67 minutes north latitude and 122 degrees 11.79 minutes west longitude. The elevation of the accident site was approximately 810 feet MSL (refer to CHART I). The first evidence of ground impact was a crater in the soil approximately 32 inches deep. The nose wheel and strut, one of the main landing gear, and the aircraft's propeller were found in this crater (refer to photograph 1). The impact crater was surrounded by high deciduous trees. An area of broken tree limbs was noted at the top of the tree canopy and the angle measured from this area of broken tree limbs to the ground impact crater was found to be -55 degrees (refer to composite panoramic photograph 2). The main wreckage (fuselage, wings, engine and empennage) came to rest at a point bearing 020 degrees magnetic from the initial ground impact crater and 45 feet distant (refer to photograph 3). The aircraft was observed in an upright attitude. Both wings were heavily damaged and there was extensive aftward compressive deformation at the forward end of the fuselage (refer to photographs 4 and 5). The engine had been torn free of the fuselage. Both wings were heavily damaged and displayed tree strike signatures. The flap jackscrew was found in a position consistent with full flap retraction. The propeller was exhumed from the impact crater and examined. One blade displayed moderate "S" bending deformation. The opposing blade displayed extensive aftward bending superimposed on "S" bending. Both forward blade surfaces displayed extensive chordwise scratching (refer to photographs 6 and 7). The horizontal and vertical stabilizers and their associated control and trim tab surfaces were examined. The top half of the vertical stabilizer and rudder panel were separated. The right horizontal stabilizer, elevator and associated trim tab remained attached to the empennage and the stabilizer's leading edge displayed extensive aftward compressive deformation (refer to photograph 8). The left horizontal stabilizer and elevator remained attached to the empennage but was severely deformed and partially separated (refer to photograph 9). The engine was examined on-site and its throttle, carburetor heat and mixture cables were torn free from the instrument panel areas of the aircraft (refer to photograph 10). The carburetor was examined and the throttle valve was observed to be in the fully open position (refer to photograph 11). Fuel was found within one of the carburetor fuel lines. The floats inside the carburetor chamber were examined and displayed "hydraulic" type compressive deformation (refer to photograph 12). The aircraft's vacuum pump, which remained attached to the engine's accessory pad, was removed and disassembled. The drive shaft was intact and the interior was free of carbon particulates and displayed several major cracks through the spool (refer to photograph 13). A control continuity examination was undertaken and there was no evidence of any pre-impact control discontinuity with any of the three control surface systems. MEDICAL AND PATHOLOGICAL INFORMATION Post mortem examination of the pilot was conducted by D. J. Wickham, M.D., at the facilities of the Clark County Medical Examiner's Office, Vancouver, Washington, on June 5, 1998 (case number 98-474SK). Toxicological evaluation of samples from the pilot was conducted by the FAA's Toxicology Accident and Research Laboratory, Oklahoma City, Oklahoma. The following findings were reported (refer to attached TOX report): 27 (mg/dl, mg/hg) ETHANOL detected in urine 17 (mg/dl, mg/hg) ETHANOL detected in muscle fluid 10 (mg/dl, mg/hg) detected in blood 06 (mg/dl, mg/hg) ACETALDEHYDE detected in blood 0.005 (ug/ml, ug/g) TETRAHYDROCANNABINOL (MARIHUANA) detected in blood 0.011 (ug/ml, ug/g) TETRAHYDROCANNABINOL CARBOXYLIC ACID (MARIHUANA) detected in blood 0.100 (ug/ml, ug/g) TETRAHYDROCANNABINOL CARBOXYLIC ACID (MARIHUANA) detected in urine 0.092 (ug/ml, ug/g) METHAMPHETAMINE detected in blood METHAMPHETAMINE detected in urine AMPHETAMINE detected in urine 0.020 (ug/ml, ug/g) AMPHETAMINE detected in blood 0.046 (ug/ml, ug/g) BENZOYLECGONINE detected in urine BENZOYLECGONINE NOT detected in blood ADDITIONAL INFORMATION On-site examination of the wreckage was conducted on June 5, 1998, and the wreckage was verbally released to H.L.M. Air Services, Independence, Oregon, for the purpose of removal and temporary storage. Formal wreckage release was accomplished with the attorney representing the estate of the pilot on July 20, 1998 (refer to NTSB Form 6120.15 attached).

Probable Cause and Findings

The pilot-in-command's failure to maintain control of the aircraft during attempted flight into instrument meteorological conditions. Factors contributing to the accident were clouds, dark night conditions, spatial disorientation, and drug impairment.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports