Aviation Accident Summaries

Aviation Accident Summary SEA03FA121

Vail, WA, USA

Aircraft #1

N6596X

Lamb (Vans) RV-4

Analysis

The pilot departed the private airstrip the morning after the proprietary runway lights had been disabled due to vandalism. He flew 1.8 hours to attend a family reunion and then departed shortly after 1930 back to his point of origination. The aircraft crashed at 2155. A relative familiar with the aircraft reported that the fuel consumption was about 8 gallons per hour and the aircraft was equipped with two 16 gallon wing tanks. There was no evidence that the pilot acquired any fuel after departing and no record of refueling for the return flight. The aircraft, which was observed flying westbound, crashed 3 miles south-southwest of the destination airstrip. Post crash examination revealed less than an ounce of fuel in the aircraft's fuel lines. The sun was approximately -7 degrees below the horizon at the time of the accident (dusk). The aircraft was observed to touch down in a 1,000 foot long open field of high grass overlying slightly rough terrain, roll a short distance and then nose over. Examination of the aircraft revealed that the standard roll bar aft of the forward pilot's seat had been replaced with a significantly lower roll bar.

Factual Information

HISTORY OF FLIGHT On June 28, 2003, approximately 2155 Pacific daylight time (PDT), a homebuilt Lamb (Van's) RV-4, N6596X, registered to and being flown by a private pilot sustained substantial damage during a forced landing and subsequent nose over in a field approximately one mile north of Vail, Washington. The pilot was fatally injured and there was no fire. Visual meteorological conditions existed and no flight plan had been filed. The flight, which was personal, was operated under 14CFR91, and originated from Grangeville, Idaho, earlier on the evening of the accident. The pilot was reported to have flown N6596X from his residence at the Flying B airstrip (8WA0) to Grangeville (S80), Idaho, for a family reunion on the day of the accident. He departed 8WA0 approximately 0930 on the morning of the accident and a family acquaintance reported that the pilot indicated the flight time for this trip was 1.8 hours. There is no record that the pilot obtained fuel at Grangeville during his stop over. There was no record at local airports near 8WA0 indicating that the pilot had acquired fuel on the date of the accident, however, acquaintances of the pilot reported that he could routinely make the 8WA0-S80 roundtrip without refueling if he departed with full fuel tanks. A relative drove the pilot to the Grangeville airport on the evening of the accident arriving approximately 1920 (PDT), and estimated that the pilot would not have departed Grangeville before 1930. On the way to the airport the relative inquired as to whether the pilot had enough fuel and the pilot indicated that he did (the pilot had flown the 8WA0-S80 roundtrip flight on numerous previous occasions). The relative also noted that the pilot wanted to get home before dark but did not convey any reason for this. Several witnesses located roughly midway between 8WA0 and the accident site reported observing the aircraft on the evening of the accident. Witnesses 1 and 4 observed the aircraft flying low (100-200) feet above ground headed west and moving at a fairly good speed. They reported hearing the engine "sputter" and then lose power. Witness 3 reported hearing the aircraft's engine "rev" twice followed by silence. He also estimated the aircraft's altitude at 450-500 feet above ground, traveling west to southwest and gradually turning south. Witness 2 heard a "sputter" and then silence as the aircraft flew west about 500 feet above ground (refer to Attachments WTC-I through IV and CHART I). A fifth witness was driving eastbound on Vail Cutoff Road about 2200 when he observed the aircraft cross in front of his vehicle heading southbound. He observed the aircraft execute a left turn to the east and land in a grass field just south of his position, and reported that the car's windows were down but he heard no engine sound. He reported that once the aircraft had landed the tail of the aircraft bounced up and the aircraft then flipped over (refer to Attachment WTC-V and CHART I) PERSONNEL INFORMATION The pilot held a private pilot certificate with airplane single-engine land ratings. His last FAA medical (third class) was issued on September 24, 2002, and contained the restriction that he "must wear corrective lenses." The pilot reported a total of 1,400 hours of flight experience at the time of this medical. No pilot logbooks or flight experience were available for review. AIRCRAFT INFORMATION N6596X, a Van's model RV-4 homebuilt, tandem place, tail wheel-equipped aircraft was built by the pilot/owner and was registered on February 5, 1991. No aircraft (airframe/power plant) logs were located and the aircraft's total time was not known. The aircraft was equipped with a single, 16 gallon fuel tank in each wing, and a relative familiar with the aircraft reported that the fuel consumption was about 8 gallons per hour. METEOROLOGICAL INFORMATION The aviation surface weather observation reported for Olympia, Washington, 12 nautical miles west of the accident site and within several minutes of the accident time reported clear conditions, 10 miles visibility and a 5 knot wind from the north. The azimuth and elevation of the sun (with respect to a flat horizon) at the accident site at 2155 on the date of the accident was determined to be approximately 315 degrees true and -7 degrees below the horizon. The environmental conditions at the time of the accident were characteristic of dusk. Witnesses 1, 3 and 4 reported dusk conditions at the time they observed the aircraft. AERODROME INFORMATION The pilot's destination and base airstrip, "Flying B," was a single bi-directional, turf runway measuring 2,200 feet in length and 60 feet in width. The runway was oriented along a 310/130 magnetic bearing. The most current FAA Form 5010 (October 1, 1993) showed the airstrip as "private" ownership and indicated that there were no approach/lighting aids for the runway (refer to attachment 5010-I). The airport manager reported that proprietary runway lights had subsequently been installed for those residents who lived at and operated their aircraft from the airstrip. The lights were controlled by means of a remote control actuator that each pilot operating out of the airstrip had been provided. Additionally, the airport manager reported that sometime during the late evening/early morning of June 27/28th the runway light system was vandalized and rendered essentially unusable. Although the pilot was reportedly aware of this circumstance, it was not known whether he was aware of the degree of damage when he departed the airstrip in daylight conditions on the morning of June 28th. The Flying B airstrip was located four nautical miles south-southwest of Western Airpark, a public use airport served by a 2,846 foot long, asphalt runway equipped with low intensity runway lights (refer to CHART II). The airport has no fuel available. WRECKAGE AND IMPACT INFORMATION The aircraft crashed in an open field consisting of three to five foot high grass on slightly rough terrain. The field measured approximately 1,000 feet in length (east to west) and was located about one mile north of Vail, Washington, and three miles south-southwest of the Flying B airstrip. The accident site coordinates (initial ground touchdown point) were determined using a hand held GPS unit and were found to be 46 degrees 51.423 minutes north latitude and 122 degrees 39.475 minutes west longitude. The elevation of the accident site was approximately 465 feet above mean sea level (MSL) (refer to CHART I). The aircraft was observed at its final resting place approximately 250 feet due east of the initial ground touchdown site (refer to AERIAL IMAGE I). The aircraft came to rest in an inverted attitude (refer to photograph 1). The aircraft sustained substantial damage primarily at the left wingtip, left and right elevators, upper vertical stabilizer, landing gear, engine cowling, propeller spinner and the cockpit canopy (refer to photographs 2 through 4). MEDICAL AND PATHOLOGICAL INFORMATION Emmanuel Q. Lacsina, M.D., conducted a post-mortem examination of the pilot at the facilities of the Thurston County Morgue, 4109 Bridgeport Way, Suite E4, University Place, Washington, on June 30, 2003, (case number 03-0815-06). The pathologist reported the cause of death as "Multiple blunt force head and neck injuries" and "Probable positional asphyxia as [a] contributing factor." The Federal Aviation Administration's Toxicology Accident and Research Laboratory, Oklahoma City, Oklahoma conducted a toxicological evaluation of samples from the pilot. All findings were negative (refer to attached TOX report). SURVIVAL ASPECTS The standard Vans RV-4 aircraft kit was equipped with a roll bar which was to be installed directly aft of the forward pilot seat. The roll bar conformed closely to the inside dimension of the canopy just aft of the forward pilot's seat and was designed to protect the forward seated pilot in the event of a rollover/nose over event (refer to DIAGRAM I). The roll bar installed in N6596X had been modified from the original "elliptical" design to a shortened, inverted "U" (refer to graphic image RB). The top of the modified roll bar reached only to the approximate height of the pilot's shoulders rather than to the upper inside radius of the canopy (refer to DIAGRAM II). TESTS AND RESEARCH The aircraft's Lycoming O-360-A1A engine and fuel system were examined at the facilities of Bill's Towing & Recovery on the morning of July 2, 2003. No fuel was found in either the left or right fuel tank and no fuel staining was evident at either wing tank gas cap. Both gas caps were removed and examined and there was no evidence of leakage or degraded "O" rings. Less than one ounce of blue fuel was recovered from the gascolator bowl (refer to graphic image GB). The fuel line into the Ellison throttle body fuel injection control was removed and no fuel was observed draining from the line. The electrically operated fuel boost pump was energized and no fuel was observed flowing out the disconnected end although the boost pump could be heard operating. With the aircraft's electrical master energized the electric fuel gauge for both the left and right tanks was observed pegged at the left side below the "empty" reading. A manual compression check of the engine established compression for all four cylinders, and rotation of the crankshaft verified continuity of the camshaft into the accessory section. A spark was generated for each of the four leads from both the left and right magnetos. Engine control and flight control continuity was verified in all cases. ADDITIONAL INFORMATION Examination of the wreckage was conducted on July 2, 2003, after which the wreckage was conditionally released via NTSB Form 6120.15 to Bill's Towing & Recovery, Yelm, Washington (see attached NTSB Form 6120.15). Written wreckage release to the pilot's estate was accomplished on July 3, 2003, and a wreckage release was sent to both the pilot's ex wife and children.

Probable Cause and Findings

A loss of engine power due to the pilot's inadequate in-flight decision by failing to refuel while en route, resulting in fuel exhaustion. Contributing factors were the non-operating (vandalized) runway lights, the pilot's delayed departure to his destination, dusk light conditions, rough/uneven terrain and high vegetation.

 

Source: NTSB Aviation Accident Database

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