South Dakota

The pilot departed on a cross country flight in a turbine-powered, multiengine airplane at night and in visual meteorological conditions. Recovered GPS data revealed that as the airplane accelerated down the runway, it drifted to the right of the runway centerline. A video recording showed that shortly after takeoff, the airplane rolled right, the nose dropped, and the airplane impacted the ground. It came to rest on its left side with both wings separated and the fuselage was highly fragmented forward of the main landing gear. A post-accident examination of the airframe and engines found no mechanical malfunctions or anomalies that would have precluded normal operation. A witness that spoke to the pilot shortly before the accident flight stated that the pilot exhibited difficulty in completing some paperwork; however, no medical reasoning for this difficulty could be determined based upon the available evidence. The investigation determined that at the time of the accident the pilot had been on duty for about 19 hours and 20 minutes, which was contrary to duty and rest regulations. At his estimated arrival time into the destination, the pilot would have accumulated about 20 hours and 54 minutes of duty time. The investigation was unable to determine if the pilot took advantage of the opportunity for rest that existed during the day, and therefore could not determine if fatigue contributed to the accident. Investigators were unable to determine the reason for the loss of control on takeoff with the available information.

The pilot and passengers flew in the day before the accident and the airplane remained parked outside on the airport ramp overnight. Light to moderate snow and freezing drizzle persisted during the 12 to 24-hour period preceding the accident. In addition, low instrument meteorological conditions existed at the time of the accident takeoff. Before the flight, the pilot removed snow and ice from the airplane wings. However, the horizontal stabilizer was not accessible to the pilot and was not cleared of accumulated snow. In addition, the airplane was loaded over the maximum certificated gross weight and beyond the aft center-of-gravity limit. A total of 12 occupants were on board the airplane, though only 10 seats were available. None of the occupants qualified as lap children under regulations. The takeoff rotation was initiated about 88 kts which was about 4 kts slower than specified with the airplane configured for icing conditions. After takeoff, the airplane entered a left turn. Airspeed varied between 89 and 97 kts during the initial climb; however, it decayed to about 80 kts as the airplane altitude and bank angle peaked. The airplane ultimately reached a left bank angle of 64° at the peak altitude of about 380 ft above ground level. The airplane then entered a descent that continued until impact. The stall warning and stick shaker activated about 1 second after liftoff. The stick pusher became active about 15 seconds after liftoff. All three continued intermittently for the duration of the flight. A witness located about 1/2-mile northwest of the airport reported hearing the airplane takeoff. It was cloudy and snowing at the time. He was not able to see the airplane but noted that it entered a left turn based on the sound. He heard the airplane for about 4 or 5 seconds and the engine seemed to be “running good” until the sound stopped. The airplane impacted a dormant corn field about 3/4-mile west of the airport. A postaccident airframe examination did not reveal any anomalies consistent with a preimpact failure or malfunction. On board recorder data indicated that the engine was operating normally at the time of the accident. An airplane performance analysis indicated that the accumulated snow and ice on the empennage did not significantly degrade the airplane performance after takeoff. However, the effect of the snow and ice on the airplane center-of-gravity and the pitch (elevator) control forces could not be determined. Simulations indicated that the pitch oscillations recorded on the flight could be duplicated with control inputs, and that the flight control authority available to the pilot would have been sufficient to maintain control until the airplane entered an aerodynamic stall about 22 seconds after lifting off (the maximum bank angle of 64° occurred after the critical angle-of-attack was exceeded). In addition, similar but less extreme pitch oscillations recorded on the previous flight (during which the airplane was not contaminated with snow but was loaded to a similar center-of-gravity position) suggest that the pitch oscillations on both flights were the result of the improper loading and not the effects of accumulated snow and ice. Flight recorder data revealed that the accident pilot tended to rotate more rapidly and to a higher pitch angle during takeoff than a second pilot who flew the airplane regularly. Piloted simulations suggested that the accident pilot’s rotation technique, which involved a relatively abrupt and heavy pull on the control column, when combined with the extreme aft CG, heavy weight, and early rotation on the accident takeoff, contributed to the airplane’s high angle-of attack immediately after rotation, the triggering of the stick shaker and stick pusher, and the pilot’s pitch control difficulties after liftoff. The resulting pitch oscillations eventually resulted in a deep penetration into the aerodynamic stall region and subsequent loss of control. Although conditions were conducive to the development of spatial disorientation, the circumstances of this accident are more consistent with the pilot’s efforts to respond to the activation of the airplane stall protection system upon takeoff. These efforts were hindered by the heightened airplane pitch sensitivity resulting from the aft-CG condition. As a result, spatial disorientation is not considered to be a factor in this accident.

Before the air taxi flight, the commercial pilot obtained a weather briefing via the company computer system and reviewed the weather information with the company chief pilot. The pilot stated that based on the computer briefing, which did not include icing conditions, he was aware of the forecasted weather conditions along the route of flight and at the intended destination. However, the briefing was incomplete as it did not contain any in-flight weather advisories, which would have alerted the pilot of moderate icing conditions expected over the flight route in the form of AIRMET Zulu. After takeoff and during the climb to 12,000 ft mean sea level (msl), the airplane encountered light rime ice, and the pilot activated the de-ice equipment with no issues noted. After hearing reports of better weather at a lower altitude, the pilot requested a descent to between 5,000 and 6,000 ft. During the descent to 6,000 ft msl and with the airplane clear of ice, the airplane encountered light to moderate icing conditions. The pilot considered turning back to another airport but could not get clearance until the airplane was closer to his destination. Shortly thereafter, the pilot stated that it felt “like a sheet of ice fell on us” as the airplane encountered severe icing conditions. The pilot applied full engine power in an attempt to maintain altitude. The airplane exited the overcast cloud layer about 500 ft above ground level. The pilot chose to execute an off-airport emergency landing because the airplane could not maintain altitude. During the landing, the landing gear separated; the airplane came to rest upright and sustained substantial damage to the wings and fuselage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation and that the airplane was within its maximum gross weight. Structural icing was observed on the airframe after the landing. Based on the weather information, which indicated the probability of icing between 5,000 and 9,000 ft over the region and a high threat of supercooled large droplets between 5,000 and 7,000 ft, it is likely that the airplane, which was equipped for flight in icing conditions, inadvertently encountered severe icing conditions consistent with supercooled large droplets, which resulted in structural icing that exceeded the airplane’s capabilities to maintain altitude.

On 1 July 2012, at approximately 1738 Local time, a C-130H3, Tail Number 93-1458, assigned to the 145th Airlift Wing, North Carolina Air National Guard, Charlotte Douglas International Airport (KCLT), Charlotte, North Carolina, crashed on public land managed by the United States Forest Service (USFS), while conducting wildland firefighting operations near Edgemont, South Dakota. At the time of the mishap all members of the Mishap Crew (MC) were assigned or attached to the 156th Airlift Squadron, based at KCLT. The Mishap Crew (MC) consisted of Mishap Pilot 1 (MP1), Mishap Pilot 2 (MP2), Mishap Navigator (MN), Mishap Flight Engineer (ME), Mishap Loadmaster 1 (ML1) and Mishap Loadmaster 2 (ML2). For the mishap sortie, MP1 was the aircraft commander and pilot flying in the left seat. MP2 was in the right seat as the instructor pilot. MN occupied the navigator station on the right side of the flight deck behind MP2. ME was seated in the flight engineer seat located between MP1 and MP2, immediately aft of the center flight console. ML1 and ML2 were seated on the Modular Airborne Fire Fighting System (MAFFS) unit, near the right paratroop door. ML1 occupied the aft MAFFS control station seat and ML2 occupied the forward MAFFS observer station seat. MP1, MP2, MN and ME died in the mishap. ML1 and ML2 survived the mishap, but suffered significant injuries. The mishap aircraft (MA) and a USFS-owned MAFFS unit were destroyed. The monetary loss is valued at $43,453,295, which includes an estimated $150,000 in post aircraft removal and site environmental cleanup costs. There were no additional fatalities, injuries or damage to other government or civilian property.

Shortly after the airplane lifted off, the tower controller informed the pilot that a plume of smoke was visible behind the airplane. No communications were received from the pilot after he acknowledged the takeoff clearance. Witnesses reported that white smoke appeared to be trailing from the area of the left engine during takeoff. The witnesses subsequently observed flames at the inboard side of the left engine. The airplane began a left turn. As the airplane continued the turn, the flames and trail of white smoke were no longer visible. When the airplane reached a southerly heading, the nose dropped abruptly, and the airplane descended to the ground. Witnesses stated that they heard an increase in engine sound before impact. A postimpact fire ensued. The accident site was located about 3/4 mile from the airport. A postaccident examination determined that the left engine fuel selector and fuel valve were in the OFF position, consistent with the pilot shutting down that engine after takeoff. However, the left engine propeller was not feathered. Extensive damage to the right engine propeller assembly was consistent with that engine producing power at the time of impact. The landing gear and wing flaps were extended at the time of impact. Teardown examinations of both engines did not reveal any anomalies consistent with a loss of engine power. The left engine oil cap was observed to be unsecured at the accident site; however, postaccident comparison of the left and right engine oil caps revealed disproportionate distortion of the left oil cap, likely due to the postimpact fire. As a result, no determination was made regarding the security of left engine oil cap before the accident. Emergency procedures outlined in the pilot’s operating handbook (POH) noted that when securing an engine, the propeller should be feathered. Performance data provided in the POH for single-engine operations were predicated on the propeller of the inoperative engine being feathered, and the wing flaps and landing gear retracted. Thus, the pilot did not follow the emergency procedures outlined in the POH for single-engine operation.

The airplane was on an instrument flight rules flight in night instrument meteorological conditions when the accident occurred. The airplane had been cleared for an ILS approach and the pilot elected to use a non-published procedure to intercept the final approach. After becoming established on the final approach, the airplane impacted the ground about 7 miles from the destination airport at an elevation approximately the same as the airport elevation. Flight inspections of the instrument approach performed prior to and subsequent to the accident revealed satisfactory performance of both the localizer and glideslope functions. The number one altimeter setting did not match the altimeter setting that was current at the time of the accident. Post accident examination of the altimeters revealed that the number one altimeter read 360 feet high. No determination was made as to whether the discrepancy existed prior to impact. However, the pilot did not report any pre-flight discrepancies with regard to the airplane's altimeters. No other anomalies were found or reported with regard to the airplane's structure or systems.

The mishap aircraft, call sign Pacer 43, was conducting pattern work operations during an off-station training mission at Ellsworth AFB, SD (RCA). Shortly before impact, the mishap crew was conducting a simulated single-engine approach to runway 31 at Ellsworth AFB. Subsequent analysis showed that there was a significantly greater amount of fuel in the left wing and left wing tip tank than the right. The gross fuel imbalance resulted from an unmonitored transfer of fuel from the right wing and right wing tip tank to the left that was initiated by the crew approximately nine and one-half minutes before impact. As the aircraft approached the point when it would normally transition to a flare, it leveled off and began a climbing turn to the west, toward the tower. It did not touch down prior to the turn, but veered left immediately during the flare, and then rolled back to wings level momentarily as it climbed. The heavier left wing, and application of power to the right engine for the go-around, caused the aircraft to roll back into a steeper left turn, stayed in a climbing left turn with the bank continuing to increase until il rolled through more than 90 degrees of bank. As the aircraft reached the highest point of the climb (approximately 450 feet), the bank angle was more than 90 degrees, and perhaps slightly inverted as the nose dropped and the aircraft began to descend. The aircraft impacted the ground in a grassy field.

On October 25, 1999, about 1213 central daylight time (CDT), a Learjet Model 35, N47BA, operated by Sunjet Aviation, Inc., of Sanford, Florida, crashed near Aberdeen, South Dakota. The airplane departed Orlando, Florida, for Dallas, Texas, about 0920 eastern daylight time (EDT). Radio contact with the flight was lost north of Gainesville, Florida, after air traffic control (ATC) cleared the airplane to flight level (FL) 390. The airplane was intercepted by several U.S. Air Force (USAF) and Air National Guard (ANG) aircraft as it proceeded northwestbound. The military pilots in a position to observe the accident airplane at close range stated (in interviews or via radio transmissions) that the forward windshields of the Learjet seemed to be frosted or covered with condensation. The military pilots could not see into the cabin. They did not observe any structural anomaly or other unusual condition. The military pilots observed the airplane depart controlled flight and spiral to the ground, impacting an open field. All occupants on board the airplane (the captain, first officer, and four passengers) were killed, and the airplane was destroyed.
Crew:
Michael Kling,
Stephanie Bellegarrigue.
Passengers:
Payne Stewart,
Van Ardan,
Bruce Borland,
Robert Fraley.

Witnesses observed the flight enter downwind for runway 30, after it had completed a published approach to runway 12, with a circle to land on runway 30. The witnesses, one of which was a commercial pilot said that there were jagged ceilings at the time about 400 to 500 feet above the ground. He and two other men with him saw the airplane below the clouds. As the airplane proceeded downwind, it momentarily entered a cloud. As the airplane came out of the cloud, it turned left in about a 30 degree turn. The angle of bank increased to about 70 to 80 degrees, the tail of the airplane came up, and the airplane impacted the ground nose first. Several pilots at the airport heard someone from N69BS make a radio transmission on the UNICOM frequency. What was heard by several people was that N69BS had broken out at 2200 feet. They then heard, 'N69BS turning base,' immediately followed by 'lookout' and 'oh ....' All of the eye witnesses agreed that at no time did they see or hear any problems with the engine. They all said that the sounds coming from the engine never changed. The published approach in use at the time of the accident was the GPS (global positioning system) runway 12. The pilot made his initial approach to runway 12, broke off the approach to the right, entered a right downwind for a landing on runway 30. The published circling minimums for the approach were MDA (minimum descent altitude) 4,800 feet, HAT (height above terrain) 869 feet. Using an approach speed of 90 knots, the minimum visibility was 1 mile. Using an approach speed of 120 knots, the minimum visibility was 1 1/4 miles. The field elevation was 3,931 feet. The profile for the GPS runway 12 approach showed that after the IAF (Jesee way point), the course was 204 degrees, at 7,000 feet, to the Dezzi way point, from Dezzi the course was 114 degrees, descend to 5,600, to Sophi way point, after Sophi descend to 4,800 feet to the missed approach point at the Ruste way point. The distance from Dezzi to Ruste was 10 miles.

The pilot landed at Watertown, loaded and off-loaded cargo, and departed without getting out of the airplane. A witness reported seeing the airplane over the runway at an altitude of about 50 feet agl. The airplane was described to be bouncing and buffeting. Another witness reported the weather as overcast with occasional snow flakes. The airplane then descended, impacted the terrain and exploded. Post accident inspection revealed a 1/2 to 3/4 inch thick ridge of rime ice along the leading edge of the left horizontal stabilizer. Pieces of arc shaped ice were located along the wreckage path. Inspection of the wreckage failed to reveal any preimpact failure/malfunction of the engine or airframe which would have prevented flight.