Wyoming

Shortly after takeoff, the pilot reported he had 'a problem...an overboost situation,' and wanted to return for landing. Instrument meteorological conditions prevailed, so the pilot was cleared for the ILS runway 26 approach. A witness saw the airplane emerge from the low overcast in a wings level descent, then pitch over to a near vertical attitude and impact a shopping center sign. The left turbocharger wastegate was found in the open (low boost) position, and the right turbocharger wastegate was found in the closed (high boost) position. The right turbocharger butterfly valve was severely eroded, the pin was missing, and the valve was free to rotate on the shaft. A hole was burnt through the right engine number 1 cylinder exhaust valve. Both propellers were in the low pitch-high rpm range. Both engines and turbochargers were original equipment and had not been overhauled in 21 years. A toxicology test showed 0.564 mcg/ml of sertraline (antidepressant) in the pilot's blood. Sertraline was not approved for use while flying an aircraft.

The aircraft was on an air ambulance (EMS) flight and was cleared for the ILS runway 08 approach at Casper, WY. Radar data showed the aircraft tracking and descending normally on the DME arc, until it was below radar coverage for the area. Subsequently, it collided with the top of a ridge, along the localizer centerline, before reaching the outer marker, about 8 miles from the airport. Elevation of the crash site was about 5,800 feet; minimum descent altitude before intercepting the ILS glide slope was 7,100 feet; crossing altitude at the outer marker was 6,700 feet. All four occupants were killed, a patient, two doctors and a pilot.

During a cross country business flight, which was filed and flown under instrument flight rules, the pilot and controller had numerous communications regarding routing and weather, and the aircraft was circumnavigating weather areas. The pilot reported entering what his stormscope showed as a 'clear' area after encountering rain and moderate turbulence at temperatures conducive to structural icing. The controller noted a 1,000 foot loss of altitude from the assigned cruise altitude of 17,000 feet, followed by a loss of altitude readout. Shortly thereafter the aircraft disappeared from the controller's radar scope. The wreckage was found near the last radar fix. The airplane impacted in a near vertical descent. All four occupants were killed.

The flight had departed Tucson, AZ, on a special VFR ferry flight to Greybull, WY. The airplane was not instrumented for IFR flight. When the flight reported over Winslow, it was advised that VFR flight was not recommended northbound from its present position. Surface weather conditions in southcentral wyoming/northwestern Colorado at the time of the accident were consistent with low ceilings, clouds and snow as reported by witnesses and surface weather observations. The witnesses, located near the Dixon Airport, reported hearing a low flying aircraft travelling west to east, and another witness northeast of the arpt heard an aircraft 'revving' its engines. Radar data shows the aircraft tracking northbound slightly east of the Dixon airport, and executing a clockwise 360° turn northeast of the airport and in the vicinity of one of the witnesses. The last radar target received placed the aircraft approximately one mile north-northeast of the accident site. The aircraft impacted snow covered terrain in a steep nose-down attitude. Both pilots were killed.

The air taxi cargo pilot crashed on a mountainside, about 7 miles from the airport, while on a VOR/DME instrument approach. Variable low ceilings and visibility had prevailed on the day of the accident. The pilot had had the flu for the preceding 2 weeks and was still taking medication. Sole on board, he was killed.

The pilot initiated a takeoff with snow and ice on the aircraft. During takeoff roll the aircraft became airborne, settled back onto the runway and the pilot attempted to abort the takeoff. The aircraft departed the end of the runway, impacted navigation antennas and rough terrain. All four occupants escaped uninjured.

The pilot and his two passengers had just arrived at the Jackson-Hole Airport (JAX) approximately 30 minutes prior to the accident. The pilot dropped off his passengers and stepped into operations for a short break. He then returned to the aircraft by himself for a return flight to California. It was a very dark night with a 2,000 feet overcast and no visible horizon. The pilot had departed Redding, CA at 1357 hours and had been on continuous flight duty from that time until the time of the accident. A witness stated the pilot seemed to be tired and hungry. The aircraft was observed making a normal night takeoff. Witnesses stated that as the aircraft turned from crosswind to downwind it appeared that the pilot had trouble controlling the aircraft. After the aircraft made a few extreme up and down maneuvers, it appeared to proceed to the east. The next time the aircraft was observed, it was again climbing and descending rapidly and subsequently impacted the ground in a vertical dive. The pilot, sole on board, was killed.

The pilot and three passengers were returning to Dallas, TX from a retreat in Montana. The pilot filed an IFR flight plan from White Sulphur Springs, MT, to Casper, WY, but did not activate it after departure. The aircraft was reported overdue by family and a search was initiated. The wreckage was located by the civil air patrol on 7/1/87. The aircraft had crashed at the 10,000 feet level of a box canyon area in mountainous terrain. The impact area was on a rolling meadow that was surrounded on three sides by mountains. Entrance to the area was from the north-northeast. There was evidence the aircraft impacted in a left wing low, nose low attitude, after turning to a heading of about 050°. Before takeoff, the pilot had added 35 gallons of fuel (mixture of 80 and 100 octane fuel) for an estimated fuel load of 213 gallons. No evidence was found of a preimpact mechanical failure or malfunction. Approximately 27 miles south-southeast of Cody, WY, the weather was in part: 18,000 feet scattered, 25,000 feet overcast, 30 miles visibility. The elevation at Cody was about 5,000 feet lower than the crash site. All four occupants were killed.

N2336X was on a business flight to Cody, WY. The pilot executed a missed approach on the first attempt of the VOR-A approach. A pilot who landed at Cody minutes before the accident said the visibility had decreased to 3/4 of a mile when N2336X made the first approach and approx 1/2 mile when N2336X crashed. Examination of the wreckage revealed no evidence of a mechanical malfunction or failure of the aircraft prior to accident. The sas servo arm was found in the full up position. The aircraft struck the terrain in a steep nose low attitude on a heading that was opposite to the direction of flight. Approach minimums at Cody are 5,800 feet and 1 mile visibility. All three occupants were killed.

On 5/1/86, the pilot had an acoustic tumor removed from his right ear which included the removal of the 8th nerve (balance nerve). His attending physician suggested approximately 1 year period of recuperation due to equilibrium problems associated with this type of surgery. On 7/12/86, he had a 1st class medical exam and received a medical certificate which was valid for flight test only. On 8/28/86, while taking off at night, the aircraft collided with rising terrain approximately 1.5 mile from the end of the runway at an elevation of about 5,600 feet. The airport elevation was 5,586 feet. A witness stated that he saw the aircraft takeoff, but it did not climb after takeoff. An investigation revealed that the accident occurred in an area that was isolated from ground lights. A post crash examination revealed no evidence of a mechanical failure or malfunction of the aircraft structure, flight controls, engine or propellers. According to the pilot's log book, his last night flight was on 3/22/85. He had been on duty for approximately 14 hours when the accident occurred. All seven occupants were killed.