Aspen-Pitkin County-Sardy Field

On August 21, 2023, about 1315 central daylight time, an Israel Aircraft Industries 1125 Westwind Astra airplane, N39TT, sustained substantial damage when it was involved in an accident near Wheeling, Illinois. The pilot and co-pilot were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 positioning flight. According to the flight crew, they were cleared to land on runway 16 at Chicago Executive Airport, Wheeling, Illinois, and the airplane touched down within the touchdown zone. The pilot applied the brakes and deployed the thrust reversers. The pilot applied additional brake pressure and “found they were not grabbing.” The pilot released the brakes and reapplied brake pressure with no effect and advised the co-pilot he had no brakes. The co-pilot applied his brakes with no effect. The pilot selected the emergency brake handle and applied emergency braking. The pilot reported the emergency braking produced some slowing, and with the airplane’s nose wheel tiller, he attempted a right turn to exit the runway onto the 45° taxiway D, which he thought provided additional stopping distance. Due to the airplane’s energy and momentum, the airplane slid off the taxiway and into the adjacent grass. The airplane’s right main landing gear collapsed, and the airplane came to rest upright.

The pilot reported that he performed the “before starting engine” and “starting engine” checklists and everything was normal before taking off in the twin-engine airplane. He performed an engine runup and then started his takeoff roll. The pilot reported that about halfway down the runway the airplane was not accelerating as fast as it should. He attempted to rotate the airplane; however, “the airplane mushed off the runway.” The airplane settled back onto the runway, then exited the departure end of the runway, where it sustained substantial damage to the wings and fuselage. The airplane engine monitor data indicated the airplane’s engines were operating consistent with each other at takeoff power at the time of the accident. Density altitude at the time of the accident was 7,170 ft and according to performance charts, there was adequate runway for takeoff. The reason for the loss of performance could not be determined.

The private pilot was conducting a personal flight during day, instrument flight rules (IFR) conditions. The pilot checked in with an air route traffic control center, and, after radar data showed multiple changes in altitude that were not in accordance with the assigned altitudes, an air traffic controller queried the pilot about the altitude changes. The pilot reported an autopilot problem and then later requested clearance to deviate around weather at a higher altitude. The airplane passed through several sectors and controllers, and it was understood that the pilot was aware of the adverse weather due to the deviation information in the flight strip. The air traffic controller did not provide additional adverse weather information and updates to the pilot, as required by a Federal Aviation Administration order; however, general broadcasts of this weather information were recorded on the frequency the pilot was using before the accident. Multiple weather resources showed rapidly developing multicellular to supercell-type convective activity with cloud tops near 48,000 ft. Forecasts and advisories warned of potential strong to severe thunderstorms with the potential for moderate-to-severe turbulence, hail, lightning, heavy rains, and high wind. Radar data indicated that the pilot turned into the intense weather cells instead of away from them as he had requested. The pilot declared a "mayday" and reported that he had lost visual reference and was in a spin. Damage to the airplane and witness marks on the ground were consistent with the airplane impacting in a level attitude and a flat spin. No mechanical anomalies were noted that would have precluded normal operation before the loss of control and impact with the ground. The investigation could not determine if there was an anomaly with the autopilot or if the rapidly developing thunderstorms and associated weather created a perception of an autopilot problem. The autopsy identified coronary artery disease. Although the coronary artery disease could have led to an acute coronary syndrome with symptoms such as chest pain, shortness of breath, palpitations, or fainting, it was unlikely to have impaired the pilot's judgment following a preflight weather briefing or while decision-making en route. Thus, there is no evidence that a medical condition contributed to the accident. The toxicology testing of the pilot identified zolpidem in the pilot's blood and tetrahydrocannabinol and its metabolite in the pilot's cavity blood, which indicated that he was using two potentially impairing substances in the days to hours before the accident. It is unlikely that the pilot's use of zolpidem contributed to the accident; however, the investigation could not determine whether the pilot's use of marijuana contributed to the cause of the accident.

The airplane, with two flight crewmembers and a pilot-rated passenger on board, was on a cross-country flight. The departure and en route portions of the flight were uneventful. As the flight neared its destination, a high-altitude, terrain-limited airport, air traffic control (ATC) provided vectors to the localizer/distance measuring equipment (LOC/DME)-E approach to runway 15. About 1210, the local controller informed the flight crew that the wind was from 290º at 19 knots (kts) with gusts to 25 kts. About 1211, the flight crew reported that they were executing a missed approach and then requested vectors for a second approach. ATC vectored the airplane for a second LOC/DME-E approach to runway 15. About 1221, the local controller informed the flight crew that the wind was from 330° at 16 kts and the 1-minute average wind was from 320° at 14 kts gusting to 25 kts. The initial part of the airplane's second approach was as-expected for descent angle, flap setting, and spoilers. During the final minute of flight, the engines were advanced and retarded five times, and the airplane's airspeed varied between 135 kts and 150 kts. The final portion of the approach to the runway was not consistent with a stabilized approach. The airplane stayed nose down during its final descent and initial contact with the runway. The vertical acceleration and pitch parameters were consistent with the airplane pitch oscillating above the runway for a number of seconds before a hard runway contact, a gain in altitude, and a final impact into the runway at about 6 g. The weather at the time of the accident was near or in exceedance of the airplane's maximum tailwind and crosswind components for landing, as published in the airplane flight manual. Given the location of the airplane over the runway when the approach became unstabilized and terrain limitations of ASE, performance calculations were completed to determine if the airplane could successfully perform a go-around. Assuming the crew had control of the airplane, and that the engines were advanced to the appropriate climb setting, anti-ice was off, and tailwinds were less than a sustained 25 kts, the airplane had the capability to complete a go-around, clearing the local obstacles along that path.Both flight crewmembers had recently completed simulator training for a type rating in the CL600 airplane. The captain reported that he had a total of 12 to 14 hours of total flight time in the airplane type, including the time he trained in the simulator. The copilot would have had close to the same hours as the captain given that they attended flight training together. Neither flight crew member would have met the minimum flight time requirement of 25 hours to act as pilot-in-command under Part 135. The accident flight was conducted under Part 91, and therefore, the 25 hours requirement did not apply to this portion of their trip. Nevertheless, the additional flight time would have increased the crew's familiarity with the airplane and its limitation and likely improved their decision-making during the unstabilized approach. Further, the captain stated that he asked the passenger, an experienced CL-600-rated pilot. to accompany them on the trip to provide guidance during the approach to the destination airport. However, because the CL-600-rated pilot was in the jumpseat position and unable to reach the aircraft controls, he was unable to act as a qualified pilot-in-command.

While the first officer was flying the airplane on a visual approach to the airport located in a steep mountain valley, the tower controller informed him that the pilot of a Citation that had landed about 10 minutes earlier had reported low-level windshear with a 15-knot loss of airspeed on short final. The first officer used the spoilers while on the left base leg and then maneuvered the airplane in an "S-turn" on the final leg to correct for a too-steep approach. Just as the airplane was about to touch down with the airspeed decreasing, the captain made several calls for "power" and then called for a "go around." However, the first officer did not add power for a go-around, and the captain did not take control of the airplane. Both pilots reported that, when the airplane was about 30 ft above ground level (agl), they felt a sensation that the airplane had "stopped flying" with a simultaneous left roll, which is indicative of an aerodynamic stall, followed by an immediate impact with terrain. After striking obstructions that completely separated the right main landing gear and the right flap, the airplane came to rest upright in the dirt on the side of the runway about 4,000 ft from the initial impact point. The airplane sustained substantial damage to the fuselage and both wings. All eight occupants evacuated through the main cabin door. There was a substantial fuel spill but no postimpact fire. Both pilots reported no mechanical malfunctions or failures of the airplane, and neither pilot reported an uncommanded loss of engine power. Data from the enhanced ground proximity warning system showed that seven warning events occurred in the last 3 minutes before the accident. The first warning was for "sink rate," and it occurred when the airplane was about 1,317 ft agl and in a 3,400-ft-per-minute descent. The last warning was for "bank angle," and it occurred about 10 seconds before touchdown as the airplane exceeded 42 degrees of bank when it was about 200 ft agl. The wind recorded at the airport at the time of the accident would have resulted in a 12-knot variable tailwind with gusts to 18 knots. The evidence is consistent with the first officer flying a non stabilized approach with a decreasing airspeed during low-level windshear conditions. The first officer did not properly compensate for the known low-level windshear conditions and allowed the airspeed to continue to decrease and the bank angle to increase until the airplane experienced an aerodynamic stall.

A witness saw the airplane approach from the east. She said that the airplane came in "pretty fast" and touched down "approximately half way down the runway." The witness said, "The nose was down. He hit the ground and within 3 seconds he was off the runway and gone. Then all you saw was smoke." The witness said when the airplane hit "the front end shook. It wobbled like a kid on a tricycle. When it shook, it kind of looked like it [the airplane] bounced. Then it was gone." The control tower operator said he heard the captain say something over the radio, which caused him to look in the direction of the airplane. The tower operator saw the airplane off the runway, the main landing gear came off behind the airplane, and the airplane caught fire. The tower operator said he saw four people get out of the airplane. The airplane came to rest in a shallow ravine approximately 331 feet north of the runway. An examination of the airplane showed impact damage to the nose gear and nose gear wheel well. An examination of the airplane's systems revealed no anomalies.

On March 29, 2001, about 1901:57 mountain standard time, a Gulfstream III, N303GA, owned by Airbourne Charter, Inc., and operated by Avjet Corporation of Burbank, California, crashed while on final approach to runway 15 at Aspen-Pitkin County Airport (ASE), Aspen, Colorado. The charter flight had departed Los Angeles International Airport (LAX) about 1711 with 2 pilots, 1 flight attendant, and 15 passengers. The airplane crashed into sloping terrain about 2,400 feet short of the runway threshold. All of the passengers and crew members were killed, and the airplane was destroyed. The flight was being operated on an instrument flight rules (IFR) flight plan under 14 Code of Federal Regulations (CFR) Part 135.

At 1350 cst, a McAlester FSS specialist gave a preflight briefing to a Cessna 421 pilot concerning IMC (instrument meteorological conditions) along the route & advised that VFR flight was not recommended. Cloud tops were at 12,000', & freezing level was at 1,600'. A PIREP at 1416 cst reported light mixed icing from 6,400' to 9,000' at Oklahoma City. At 1424 cst, the pilot departed Tulsa (VFR), then radar service was terminated. No further communication was received from the airplane. Radar data showed that it climbed westerly, reaching 9,800' at 1440 cst; during the next 88 seconds, its heading & altitude deviated until it descended through 3,200'. Ground witnesses saw the airplane descend out of low clouds in a 'flat spin' & crash. No preimpact mechanical failure was found. The airplane's gross weight was about 150 lbs over its maximum limit. In November 1995, the pilot received 10 hrs of Cessna 421 simulator training; his instructor noted in training records that he met minimum standards for VFR, but 'under IMC conditions,' he 'could not maintain altitude within 1,300 feet or heading within 40 degrees.' Postmortem toxicology tests showed 0.079 mcg/ml Nordiazepam (metabolite of Valium) in kidney fluid, 0.044 mcg/ml Desipramine (metabolite of Imipramine, an antidepressant) in spleen fluid, 0.733 mcg/ml Diphenhydramine (Benadryl) in spleen fluid, & 0.353 mcg/ml Diphenhydramine in lung fluid. These medications are not approved by the FAA for use while flying. The airplane was equipped for flight in icing & IFR
conditions.

The flight crew reported to the tower controller that they were over the airport and requested a right downwind circling approach to runway 15. The tower controller and other witnesses observed the airplane in a steep right bank on base leg. The airplane overshot the extended runway centerline. The tower controller observed the airplane entering a steeper right bank to correct back to the runway centerline. The controller stated that he observed the airplane "flutter" and then crash right-wing first, about one mile north of the runway threshold. Other witnesses reported a variety of indications consistent with a loss of control. The last recorded transmission was "Oh no you're (stall…)." The ( ) indicates that the word was questionable text. Both engines were producing about 1,700 pounds of thrust (2,561 pounds available). A snow squall had just passed over the airport and was obscuring mountains to the east. The terrain was snow covered. The accident occurred about eight minutes before official sunset. The approach procedure is not authorized at night or for category D airplanes. Minimums for the approach were three miles visibility with an MDA of 10,840 feet. Airport elevation is 7,815 feet. Both pilots were rated in the airplane. It could not be determined which pilot was at the controls at the time of the accident.

The Cessna 208A was on an IFR flight to haul freight from Aspen to Denver, Colorado. Moderate to heavy icing conditions were forecast for the Denver area. While on an ILS runway 36 approach, the aircraft encountered icing conditions. Subsequently, it entered a steep descent and crashed about 3 miles from the approach end of the runway. No preimpact part failure of the aircraft was found during the investigation. The 1950 mst weather at the airport was in part: 800 feet scattered, 1,000 feet broken, visibility 4 miles with freezing drizzle and snow showers, temp 28°, dew point 25°.