Salt Lake City

Shortly after takeoff, the pilot reported to air traffic control he needed to return to the airport to land. The controller asked the pilot if he required any assistance, and the pilot responded, "negative for right now uh just need to get in as soon as possible." The controller then asked the pilot what the problem was, in which the pilot responded, "stand by one minute." Approximately 30 seconds later and while the airplane was on a left downwind to runway 35R, the pilot stated he was declaring an emergency and "...we've got an air an engine ta shut down uh please roll the equipment." The controller and other witnesses observed the airplane on the base leg and then overshoot the final approach to runway 35R. After observing the airplane overshoot the final approach, the controller then cleared the pilot to the next runway, runway 28, and there was no response from the pilot. The controller observed the airplane's landing lights turn down toward the terrain, and "the MU2 was gone." A witness observed the airplane make an "immediate sharp bank to the left and descend to the ground. The impact appeared to be just less than a 45 degree angle, nose first." A performance study revealed that while the airplane was on downwind, the airplane started to bank to the left. The bank angle indicated a constant left bank angle of about 24 degrees as the airplane turned to base leg. Twenty-three seconds later, the bank angle began to increase further as the airplane turned to final approach, overshooting the runway, while the angle of attack reached stall angle of about 17 degrees. The flight path angle then showed a decrease by 22 to 25 degrees, the calibrated airspeed showed a decrease by 40 to 70 knots, and the vertical speed indicated a 3,000 feet per minute descent rate just before impact. Examination of the airframe revealed the flaps were in the 20 degree position, and the landing gear was retracted. According to the airplane flight manual, during the base leg, the flaps should remain in the 5 degree position and the landing gear extended; and when landing is assured, the flaps then extended to 20 degrees and maintain 125 knots calibrated airspeed (KCAS) during final and 110 KCAS when over the runway. Minimum controllable airspeed (Vmc) for the airplane is 99 KCAS. Examination of the propellers revealed that at the time of impact, the left propeller was in the feathered position and the right propeller was in the normal operating range. Examination of the left engine revealed static witness marks on several internal engine components, and no anomalies were noted that would have precluded normal operation. The reason for the precautionary shutdown of the left engine was not determined. Examination of the right engine revealed rotational scorring and metal spray deposits on several internal engine components. Four vanes of the oil pump transfer tube were separated and missing. The gearbox oil-scavenge pump was not free to rotate and was disassembled. Disassembly of the oil-scavenge pump revealed one separated oil pump transfer tube vane was located in the pump. Pitting and wear damage was noted on all of the roller bearing elements and the outer bearing race of the propeller shaft roller bearing. No additional anomalies were noted.

Weather reporting facilities reported icing conditions in the area of the accident site. The pilot of a Cessna Citation flying the same RNAV approach twenty minutes prior to the accident aircraft reported picking up light to occasional moderate rime ice. The last communication between the local air traffic controller and the accident pilot indicated that the flight was two miles south of the final approach fix. The controller inquired if the pilot had the runway in sight, and the pilot reported "negative, still IMC." A witness on the ground near the accident site reported that he heard the aircraft first then saw it at a low level below the cloud base flying in a southeasterly direction. The witness stated that the right wing was lower than the left as the aircraft continued to descend. The witness then noted that the wings were moving "side to side" (up and down) a couple of times before the nose of the aircraft dropped near vertical to the terrain. This witness reported hearing the sound of the engine running steady throughout the event. The wreckage was located in a flat open field about 3,000 feet south of the final approach fix coordinates. The aircraft was destroyed by impact damage and a post crash fire.

At 1407:11 the flight was cleared from Flight Level (FL) 240 to descend and maintain FL190. At 1409:08 the controller cleared the flight to descend and maintain 15,000 feet, and at 1409:17 the pilot read back the clearance in its entirety. At 1410:20 the controller instructed the pilot to expedite his descent through 16,000 feet for traffic; however, there was no response. From 1410:33 to 1417:21 the controller made ten attempts to contact the pilot; again, there was no response. At 1417:26 the controller requested the pilot to ident if he could still hear him. At 1417:38 the controller received an ident from the aircraft and instructed the pilot to descend and maintain 15,000 feet. At 1418:36 the controller cleared the aircraft for the GPS approach and to acknowledge with an ident. There was no response. The aircraft had impacted a rocky drainage trench near the base of rock outcropping on a magnetic heading of 200 degrees in a wings level, approximately 40-degree nose down attitude, 15 nautical miles east-southeast of the destination airport at an elevation of 5,630 feet mean sea level. An examination of the aircraft's flight control, pressurization, and electrical systems revealed no anomalies with these systems which would have precluded normal operations. A further examination of the thermal damage to the aircraft, determined that there was no evidence of an inflight fire. Both engines underwent a complete teardown examination revealing no evidence of catastrophic or pre accident failure, and that both engines were functioning at the time of impact. Radar data revealed the aircraft was in level flight at FL 190 for more than 4 minutes, when it had previously been cleared to 15,000 feet. It subsequently began a climb reaching an altitude of 20,300 feet before beginning a right descending turn followed by a left descending turn. The last radar return before radar contact was lost indicated the aircraft was at 15,900 feet and descending. No evidence was available that suggests icing greater than light rime icing was present in the area and that weather was unlikely to have been a factor in the accident. The pilot was on two medications for high blood pressure and one for high cholesterol. The pilot had recently been found to have an elevated blood sugar, suggesting early diabetes or some other systemic disease or injury. The pilot had a family history of heart disease and high blood pressure, and had at least one episode of chest tightness in the past. It is possible that he had some unrecognized heart disease. The circumstances of the accident suggest substantial impairment or incapacitation of the pilot. It is possible that the pilot experienced an event such as a stroke or heart attack related to his previous medical conditions or as a new occurrence. It is also possible that he became hypoxic as a result of a decompression event without using supplemental oxygen. There is insufficient information to conclude any specific cause for the pilot's impairment or incapacitation

The Piper Aerostar 602P aircraft, registration N88AT, serial number 62P08628165003, with the pilot, who was also the owner, three passengers, and two dogs on board, took off from the Salt Lake City Airport, Utah, on an instrument flight rules flight to Penticton, British Columbia. At 1149 Pacific standard time, the Kamloops/Castlegar sector controller of Vancouver Centre passed N88AT a special weather observation for Penticton: Awinds calm; visibility : mile in snow; sky obscured; vertical visibility 700 feet; remarks snow eight [8/8 of the sky covered]; temperature zero; 1900 [1100 Pacific standard time] altimeter 30.21.@ When approaching Penticton, the pilot requested the localizer distance-measuring equipment B (LOC DME-B) approach to runway 16. When the pilot confirmed that he could complete the procedure turn within 13 miles of the Penticton airport, the controller issued an approach clearance for the LOC DME-B approach, with a restriction to complete the procedure turn within 13 miles of the Penticton airport. This restriction was to prevent possible conflicts between N88AT and aircraft taking off or carrying out missed approaches from runway 15 at Kelowna. The pilot reported to the Penticton Flight Service Station at 1203 Pacific standard time that he was by the Penticton non-directional beacon (NDB) outbound on the localizer, and he was given the latest runway condition report. When the aircraft then failed to respond to numerous radio calls from the Penticton Flight Service Station and Vancouver Centre, search and rescue staff were notified and a search initiated. The wreckage was found two days later, near the summit of Okanagan Mountain, in a wooded area, at an elevation of about 5100 feet above sea level. There were no survivors. The aircraft was destroyed but did not catch fire.

The flight was on a coupled instrument landing system (ILS) approach with 1/2 mile visibility in snow showers. Three successive fixes on the localizer are defined by distance measuring equipment (DME) paired with the ILS; prior to the ILS DME commissioning 6 months before the accident, the DME fixes were defined by a VORTAC 4.7 nautical miles past the ILS DME. The aircraft was 800 feet high at the first fix and 1,500 feet high at the second, but approximately on altitude 4.7 nautical miles past the first and second fixes, respectively. It passed the outer marker 900 feet high and captured the glide slope from above about 1.8 nautical miles from the threshold, 500 feet above decision height (DH) and 700 feet above touchdown. The aircraft was on glide slope for 28 seconds, during which time its speed decayed to stall speed; it then dropped below glide slope and crashed 1.3 nautical miles short of the threshold. The pilot's FLT DIR DME-1/ DME-2 switch, which control the DME display on the pilot's horizontal situation indicator (HSI), was found set to DME-2; the NAV-2 radio was set to the VORTAC frequency. Up to 800 feet may be required for stall recovery.

The DC-3C took off on runway 10L and immediately executed a right turn followed by a left turn back toward the airport declaring a fire aboard. Dark night visual meteorological conditions existed. Witnesses observed 'flames' or an 'orange glow' coming from the right engine. A small number of aluminum fragments identified from the aft edge of the right engine accessory cowling were found along the ground just short of the ground impact site. These fragments displayed signs of heat distress but no significant melting. An examination of the right engine and accessory section revealed no evidence of a preimpact fire, and sooting and metal splatter on the leading edge of the right horizontal stabilizer was minimal. Spectral analysis of radio transmissions revealed no evidence of significant divergence of engine RPM between the two engines. Postcrash propeller examination revealed approximate blade pitch angles of 18-19° and 30-32° for the right and left propellers respectively upon impact. Propeller slash mark dimensions associated with the right propeller resulted in propeller RPM of approximately 1,750 to 2,570 over a range of 68 to 100 knots respectively. The first officer advised the PIC (broadcasting over the tower frequency) 'we're gonna stall' approximately 10 seconds before the impact. The aircraft was in a left turn back toward runways 28 left and right when the right wing struck the ground and the aircraft cartwheeled to a stop. A postcrash fire destroyed the cockpit area and inboard right wing.

A Mitsubishi MU-2 departed Salt Lake City, Utah, and climbed to 16,000 feet MS on an IFR flight to Pocatello, Idaho. While in cruise flight, the MU-2 encountered structural icing conditions. According to radar data, the MU-2 began slowing from a cruise speed of about 190 knots with slight deviations from heading and altitude. The airspeed decreased to about 100 knots, and the flight crew declared an unspecified emergency, then radio contact was lost. The MU-2 began a right turn, then it entered a steep descent and crashed. The pilot of a Beech 1900 (about 12 minutes in trail of the MU-2), stated that he encountered moderate rime icing at 16,000 feet. The Beech pilot activated his deice boots (3 times) and descended to 12,000 feet to exit the icing conditions. The MU-2 flight manual warned that during flight in icing conditions, stall warning devices may not be accurate and should not be relied upon; and to minimize ice accumulation, maintain a minimum cruise speed of 180 knots or exit the icing conditions. An investigation determined that the captain of the MU-2 was aware of deficiencies in the timer for the deice boots, as well as other maintenance deficiencies. The captain's medical certificate was dated 11/17/94; he was providing executive transportation for compensation under an agreement for "contractual flights," under 14 CFR 91. Although icing conditions were forecast in the destination area, no icing was forecast for the en route portion of the flight.

The flight took off at 0500 hours in dark visual meteorological conditions. Radar data indicates that the flight was heading in an easterly direction, towards its destination and had climbed to and leveled off at 12,500 feet. Three minutes prior to the last identified radar target, the pilot obtained a partial weather briefing, for the destination airports, from the flight service station. The wreckage was located in an area of high mountainous terrain. Evidence indicated that the flight collided with a ridge line at the 12,400 foot level. The main wreckage was located on the east side of the ridge at 11,400 feet. During the post crash investigation, there was no evidence of a mechanical failure or malfunction. Both occupants were killed.

During arrival, the flight crew of SkyWest Airlines flight 5855 requested a VOR/DME-B approach to the Elko Airport, which was approved. As the approach continued, the flight crew reported over the Bullion VOR. Approximately 30 seconds later, the aircraft crashed. Impact occurred at the top of a mountain, about 100 feet before reaching the VOR station. Elevation of the crash site was about 6,460 feet; minimum published crossing altitude at the VOR was 7,000 feet. The airport was 4.1 miles from the VOR at an elevation of 5,135 feet.

The instrument rated pilot took off from his home, uncontrolled airport, for a flight under visual flight rules to a distant airport. A ground witness stated that instrument meteorological conditions existed at the airport of departure at the time of the takeoff. The pilot inadvertently entered instrument meteorological conditions, began an uncontrolled descent, and collided with the terrain. The pilot, sole on board, was killed.