BATTLE GROUND, WA, USA
N1668P
Piper PA-18-150
The private pilot removed the fuel selector valve handle assembly and had the placarded backing panel painted. During reinstallation, the pilot improperly placed the handle and pointer 90-degrees counterclockwise from the correct selector valve position. During the accident flight, the handle was placed in the right tank position indication, but the actual valve position was in the fuel shutoff position. The engine was subsequently starved of fuel and quit. The pilot initiated a forced landing onto wooded terrain and was seriously injured. Further exam of the valve revealed that it was improperly inspected by a mechanic, thus eliminating the detent function only. The engine fuel primer was found unlocked. Exam of the engine and airframe did not reveal any other preimpact mechanical discrepancies. The pilot had been denied a medical certificate due to an unexplained history of alcohol abuse. The FAA revoked the pilot's airman certificate for failure to provide blood test results from blood drawn after the accident.
On November 15, 1997, about 1435 Pacific standard time, N1668P, a Piper PA-18-150, operated by the owner/pilot, collided with trees during a forced landing and was substantially damaged near Battle Ground, Washington. The forced landing was precipitated by a loss of engine power during initial climb after takeoff. The private pilot was seriously injured and his passenger received minor injuries. Visual meteorological conditions prevailed and no flight plan had been filed. The personal flight was conducted under 14 CFR 91. According to interviews of the pilot that were conducted by the Safety Board (records of interview attached), the pilot stated that on the day of the accident, he departed from his private grass airstrip in Battle Ground and flew to Evergreen Field in Vancouver, Washington, to refuel. He stated that he shut down the airplane when he reached the fuel pump, and he "topped off" both wing fuel tanks himself. He then started the engine without difficulty, and departed from Evergreen Field without performing an engine "run-up." He stated that he then landed back at his grass airstrip, taxied to the end of the strip, and shut down the engine. The pilot stated that he then boarded his passenger and started the engine after using the engine fuel primer once or twice. He stated that he could remember locking the primer in place after using it. After the engine was started, he took off. As he was climbing about 300 feet per minute, "the fire went out" and the engine "stopped dead." He stated that it did not sputter or cough, it just "went dead." The pilot stated that he did not attempt to restart the engine, other than moving the fuel selector valve. He stated that he immediately moved the control stick forward to get the nose down. He also remembered that he moved the fuel selector valve from what he thought was the left tank position to the right tank position. He was shown a diagram during the interview of the fuel selector, and indicated that the pointer was the small triangular-shaped pointer opposite of the longer handle (which is the correct indication for the fuel selector). The pilot further stated that he did not attempt to perform a 180-degree turn, and instead headed toward a clearing in the trees. The airplane struck a tree and this was the last thing that he remembered. According to a Federal Aviation Administration (FAA) aviation safety inspector from Hillsboro, Oregon, the airplane impacted trees and terrain about 3,000 feet northwest of the departure airstrip. The surrounding terrain was rolling and heavily wooded. The right wing was substantially damaged. Both fuel tanks were about three-quarters full. No evidence of fire was noted. No baggage was found aboard the airplane. According to the Clark County Sheriff's Office report of the accident (attached), the pilot, who was seated in the front seat, was wearing a four-point seat restraint system at the time of the accident. The passenger, seated in the rear, was wearing a lap belt. The rear seat was not equipped with a shoulder harness. The fuel selector valve was placed in the off position during rescue. The wreckage was removed under the direction of the Safety Board for future examination. On November 25, 1997, the wreckage underwent additional examination by the Safety Board. The examination revealed substantial impact damage to both wings, all lift struts, cabin area, firewall, engine, and propeller. No evidence of a preimpact flight control system malfunction was found. The flaps were found in the retracted position. Pieces of evergreen branches were imbedded into the right wing tip. The airplane had been modified with the installation of a Lycoming O-360-A3A 180-horsepower engine, tundra tires, and an extended baggage compartment. Examination of the cockpit instruments revealed that the tachometer time read 1,642.47 hours. The engine fuel primer was found about halfway in the open position and was not locked. The throttle and mixture controls were in the full forward position, and the carburetor heat was in the off position. The engine remained attached to the airframe by its mounts. The fixed pitch propeller remained attached to the crankshaft and exhibited aft bending and leading edge scoring on one of its two blades. The other blade did not exhibit any notable deformation. Crankshaft and camshaft continuity to the rear engine-driven accessories and all valves was confirmed by manually rotating the propeller. The crankshaft rotated freely and valve action was observed on all valves. Both magnetos remained attached to the rear engine mounting location and did not appear damaged. The left magneto was tested and found to produce a spark on all four leads when manually rotated. The right magneto could not be accessed for testing; it was crushed aft into the firewall. All top spark plugs were removed and examined; they were all gray in color and exhibited oval shaped electrodes. The carburetor bowl was found to contain a liquid that was similar in color, texture, and odor to 100 low lead aviation gasoline. No preimpact mechanical malfunctions were found during the examination of the engine. The Safety Board removed the airplane's ignition switch and sent it to Teledyne Continental Motors in Atlanta, Georgia, for examination and testing. The examination and testing occurred on December 3, 1997, under Safety Board supervision (report attached). No malfunctions or anomalies were found. Examination and functional testing of the fuel selector valve in-situ revealed that it was installed 90 degrees counter-clockwise form the correct position of the valve stem. With the fuel selector handle in this position, it was determined through the application of airflow into the fuel lines that the fuel selector was actually feeding from the right tank when the pointer was reading LEFT. When the pointer was selected such that it indicated the OFF position, the selector was feeding from the left tank. When the pointer was selected to such that it indicated the RIGHT position, the valve was actually in the off position. When the selector handle was rotated during the testing, no detents could be felt as the selector was changed from one position to another (Diagrams of correct versus in-situ fuel selector valve operation are attached). The selector valve was then removed for further examination by the Safety Board. The valve itself was undamaged and remained intact. Functional testing with the use of air into each port of the valve revealed similar results to the in-situ findings that verified an incorrectly installed handle assembly. The valve stem was noted to be square in shape and did not exhibit the D-shape found on the back side of the handle. The valve itself was then disassembled one piece at a time. The disassembly revealed that the spring retaining washer was incorrectly installed upside down, which prevented the spring from applying pressure onto the slotted detent washer. With the valve assembled in this fashion, the detent feature of the valve was eliminated. Examination of the airframe records (excerpts attached) revealed an entry, dated January 15, 1997, that indicated a new O-ring was installed in the fuel selector valve. This is the most recent entry of work being performed on the valve that would have required some disassembly of it. The entry also cited compliance with FAA Airworthiness Directive 60-10-08 (excerpt attached) which pertains to checking the detent function and correct rigging of the valve such that the pointer is properly aligned to the placarded fuel tank locations. The entry further states that the detents in the valve were "OK." The records indicate that the airplane and engine received an annual inspection on the same date of the fuel selector O-ring change. The entry indicated that the tachometer time read 1,611.40 hours (31.07 hours before the accident). No other entries were found subsequent to this entry. The pilot stated that he did not perform any of his own maintenance on the airplane prior to the accident. He initially stated that he never removed the fuel selector valve handle, and had frequently moved the handle during his flying of the accident airplane on the days, weeks and months prior to the accident in order to manage his fuel load during those flights. He stated that he had never had any previous engine problems as a result of the fuel selector valve position. The pilot stated that he had been flying the accident airplane frequently during the weeks and months preceding the accident. He stated that he had accumulated about 60 hours of flying time in it during the last 90 days. During that time, he performed some "trim" painting of the exterior of the airplane. He stated that a company called "Northwest Powder Coat" performed the interior painting, including the cockpit side panels. The painting also involved the exterior of the airplane, and occurred about two or three months prior to the accident. In an interview with the paint shop owner of a business called "Mr. Powder Coat" (record of interview attached), the paint shop owner stated that the accident pilot installed an alarm system for him in February of 1997. In order to reimburse the pilot, the paint shop owner agreed to paint parts of the pilot's airplane. The paint shop owner stated that the pilot and his girlfriend would bring various airplane parts over to Mr. Powder Coat from time to time beginning in March 1997 and ending "about a month before the Evergreen Fly-In." (Subsequent research revealed that the Fly-in occurs during the third week in August.) The paint shop owner stated that he saw the pilot's airplane at the Evergreen Fly-in, and he stated that he "believed it was all together" with the newly painted parts, including the left side panel where the fuel selector valve is located. The paint shop owner went on to state that he never removed or installed parts on the airplane, and that he would only be brought parts after the pilot removed them from the airplane or purchased new parts. The paint shop owner stated that he recalled painting the left interior side panel of the airplane, and that he did not perform the stencil work to print the "LEFT," "RIGHT," or "OFF." He stated that he does not have the capability or talent to perform lettering. The paint shop owner also stated that he simply painted the panel red and gave in back to the pilot. The paint shop owner stated that he could not remember exactly when he painted the panel, but he said it was before he painted the spinner of the airplane, which was the last item he painted on the accident airplane about one month prior to the fly-in. The pilot was asked about the side panels of the airplane. He stated that before he removed them, he took a "razor knife" and made a mark in the fuel selector stem so that the proper alignment of the selector pointer was marked. He stated that he then removed the handle, and had the panel painted. He stated that when he got the panel back, he used stencils and the painted the "LEFT," "RIGHT," and "OFF" marks on it. He then reinstalled the panel himself. He stated that after he reinstalled the selector handle, he tested the system to ensure that the installation was proper. He stated that to initiate the test, he emptied the airplane of fuel. He then added fuel to the right tank only, and placed the selector valve in the "RIGHT" position. He stated that he observed fuel coming out of the fuel strainer during this scenario, and that no fuel was observed when the selector was placed in the "OFF" position. He then repeated this process with the left tank; he stated that no anomalies were noted. The accident pilot stated that on the day of the accident, he took off and flew for "about five minutes" before the engine quit. He reiterated that he did not switch fuel tanks prior to the engine failure, and that he had "no reason" to switch tanks. The accident pilot stated that he could not explain why the fuel selector valve was found in the incorrect position in the wreckage. He stated that he did not perform maintenance on it after he reinstalled the newly-coated panel. He estimated that he had flown the airplane about 40 hours since the reinstallation of the panel, and the engine never exhibited any sudden engine stoppages since then. The accident pilot also stated that he had never felt any detents in the selector valve as long as he had owned the airplane, and he vaguely remembered something about an airworthiness directive related to the fuel selector valve. The pilot reported that he had accumulated about 990 hours of total flight time. According to FAA records, the pilot was granted a private pilot certificate with a rating in airplane single-engine land on July 18, 1980. FAA records (copies attached) also indicate that the pilot did not hold a valid medical certificate at the time of the accident. The pilot applied for a medical certificate on July 14, 1997, four months prior to the accident. The FAA subsequently sent a letter to the pilot requesting additional information regarding the pilot's history of alcohol abuse and informed the pilot that his medical application was pending until the information was received and reviewed. The pilot failed to the respond to the FAA letter, and the FAA subsequently denied the pilot's medical certificate. On December 11, 1997, the FAA issued an Administrative Subpoena (copy of cover letter attached) to the Southwest Washington Medical Center in Vancouver to obtain the results of the pilot's blood test which was performed on blood taken from the accident pilot about one hour after the accident. The Medical Center refused to acknowledge the FAA subpoena. On December 23, 1997, the FAA sent a Certified Mail Letter (copy attahed) to the accident pilot requesting that the pilot authorize a release for medical information under Title 14 CFR Part 91.17. The pilot refused to authorize the release and the FAA subsequently revoked the pilot's airman certificate.
The owner/pilot's failure to properly install the fuel selector valve after removal, subsequently leading to a false indication on the valve selector handle. This led to the pilot unintentionally closing the valve and starving the engine of fuel during the initial climb.
Source: NTSB Aviation Accident Database
Aviation Accidents App
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