Tennessee

The airplane departed Chattanooga-Lovell Field Airport Runway 20 at 2225LT on a cargo flight (FDX1376) to Memphis with a crew of three on board. While climbing at night, the crew reported technical problems with the landing gear. The crew continued to the north, followed a circuit then completed a low pass over runway 20 at 2256LT. A second low pass was completed at 2319LT then the crew made a belly landing at 2347LT. The airplane slid on the runway then veered off runway and came to rest in a grassy area with both engines damaged. All three crew members evacuated safely.

The instrument-rated pilot of the business jet airplane, pilot-rated passenger, and five passengers departed on a cross-country flight and entered the clouds while performing a climbing right turn. The airplane then began to descend, and air traffic control (ATC) asked the pilot to confirm altitude and heading. The pilot did not respond. After a second query from ATC, the pilot acknowledged the instructions. The airplane entered a climbing right turn followed by a left turn. After ATC made several attempts to contact the pilot, the airplane entered a rapid descending left turn and impacted a shallow reservoir at a high rate of speed. Postaccident examination of the recovered wreckage and both engines revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. Flight track data revealed that after takeoff, the airplane entered the clouds and made a series of heading changes, along with several climbs and descents, before it entered a steep, descending left turn. This type of maneuvering was consistent with the onset of a type of spatial disorientation known as somatogravic illusion. According to a National Transportation Safety Board performance study, accelerations associated with the airplane’s increasing airspeed were likely perceived by the pilot as the airplane pitching up although it was in a continuous descent. This occurred because the pilot was experiencing spatial disorientation and he likely did not effectively use his instrumentation during takeoff and climb. As a result of the pilot experiencing spatial disorientation, he likely experienced a high workload managing the flight profile, which would have had a further adverse effect on his performance. As such, the airplane entered a high acceleration, unusual attitude, descending left turn from which the pilot was not able to recover. The pilot and the pilot-rated passenger did not report any medication use or medical conditions to the Federal Aviation Administration on their recent and only medical certification examinations. Postaccident specimens were insufficient to evaluate the presence of any natural disease during autopsy. However, given the circumstances of this accident, it is unlikely that the pilot’s or pilot-rated passenger’s medical condition were factors in this accident. Low levels of ethanol were detected in the pilot’s muscle tissue and the pilot-rated passenger’s muscle and kidney tissue; n-butanol was also detected in the pilot’s muscle tissue. Given the length of time to recover the airplane occupants from the water and the circumstances of this accident, it is reasonable that some or all of the identified ethanol in the pilot and the pilot-rated passenger were from sources other than ingestion. Thus, the identified ethanol in the pilot and the pilot-rated passenger did not contribute to this accident.

The pilot was conducting a cross-country flight and was beginning an instrument flight rules approach from the south. Weather conditions at the destination airport included a ceiling between 800 and 1,000 ft and light rime icing conditions in clouds; the pilot was aware of these conditions. Elevated, wooded terrain existed along the final approach course. Radar and automatic dependent surveillance-broadcast data revealed that the airplane crossed the intermediate approach fix at the correct altitude; however, the pilot descended the airplane below the final approach fix altitude about 4 miles before the fix. The airplane continued in a gradual descent until radar contact was lost. No distress calls were received from the airplane before the accident. The airplane crashed on a north-northwesterly heading about 5 miles south of the runway threshold. The elevation at the accident site was about 1,880 ft, which was about 900 ft higher than the airport elevation. Postaccident examination of the airframe, engines, and propellers revealed no evidence of a pre-existing mechanical failure or anomaly that would have precluded normal operation. Because of the weather conditions at the time of the final approach, the pilot likely attempted to fly the airplane under the weather to visually acquire the runway. The terrain along the final approach course would have been obscured in low clouds at the time, resulting in controlled flight into terrain.

The pilots were conducting a visual flight rules cross-country flight with three passengers onboard. The preflight, departure, and cruise portions of the flight were uneventful. During the initial approach to the airport, the flight crew discussed having some difficulty visually acquiring the airport. They also discussed traffic in the area and were maneuvering around clouds, which may have increased the pilots' workload. As the approach continued, the airplane crossed a ridgeline at 710 ft above ground level (agl), which triggered a terrain awareness and warning system (TAWS) alert. Further, the flight crew made several comments about the airplane flying too fast and allowed the airspeed to increase well above the reference speed (Vref) for the approach. At 1535:57 (about 1 minute 52 seconds before landing), the pilot pulled back the throttles to idle, where they stayed for the remainder of the approach. In an attempt to slow the airplane for landing, the pilot partially extended the speedbrakes when the airplane was below 500 ft agl, which is prohibited in the airplane flight manual (AFM). Five seconds before touchdown, the airplane's descent rate was 1,500 ft per minute (fpm), which exceeded the maximum allowed for landing per the AFM of 600 fpm. When the airplane first touched down, it was traveling about 18 knots above Vref. The pilot did not extend the speedbrakes upon touchdown, which the landing checklist required, but instead attempted to deploy the thrust reversers immediately after touchdown, which was a later item on the landing checklist. However, the thrust reversers did not unlock because the airplane bounced and was airborne again before the command could be executed, which was consistent with system design and logic: the thrust reversers will not unlock until all three landing gear are on the ground. The airplane touched down four times total; on the third touchdown (after the second bounce), when all three landing gear contacted the runway, the thrust reversers unlocked as previously commanded during the first touchdown. Although the pilot subsequently advanced the throttles to idle, which would normally stow the thrust reversers, the airplane had bounced a third time and had already become airborne again before the thrust reversers could stow. When the airplane became airborne, the system logic cut hydraulic power to the thrust reverser actuators; thus the reversers would not stow. The thrust reversers were subsequently pulled open due to the aerodynamic forces. The pilot attempted to go around by advancing the throttles when the airplane was airborne. However, the electronic engine controls prevented the increase in engine power because the thrust reversers were not stowed. When the airplane touched down the fourth and final time, the pilot attempted to land straight ahead on the runway; the airplane touched down hard and the right main landing gear then collapsed under the wing. The airplane departed the paved surface and came to rest about 600 ft beyond the runway threshold. The passengers and crew eventually evacuated the airplane through the main cabin door, and the airplane was destroyed in a postaccident fire. A postaccident examination of the airplane systems, structure, powerplants, and landing gear revealed no evidence of mechanical malfunctions or anomalies that would have precluded normal operation. The airplane's approach was unstabilized: its airspeed during the approach and landing well exceeded Vref and its descent rate exceeded the maximum allowed for landing just seconds before touchdown. Both the pilot and copilot commented on the airplane's high speed several times during the approach. During short final, the pilot asked the copilot if he should go around, and the copilot responded, "no." Although the copilot was the director of operations for the flight department and the direct supervisor of the pilot, the pilot stated that the copilot's position did not influence his decisions as pilot-in-command nor did it diminish his command authority. Neither the pilot nor copilot called for a go-around before landing despite awareness that the approach was unstabilized. As the airplane touched down, the pilot failed to follow the AFM guidance and used the thrust reversers before the speedbrakes. According to the airplane manufacturer's calculations, the airplane could have stopped within the length of runway available if the airplane had not bounced and the speedbrakes and wheel brakes were used at the point of the first touchdown. After the third touchdown, when the airplane became airborne again, the pilot attempted a go-around; the AFM prohibits touch-and-go landings after the thrust reversers are deployed. It is critical for pilots to know the point at which they should not attempt a go-around; a committed-to-stop (CTS) point is the point at which a go-around or rejected landing procedure will not be initiated and the only option will be bringing the aircraft to a stop. Establishing a CTS point eliminates the ambiguity for pilots making decisions during time-critical events. The FAA issued Information for Operators 17009, "Committed-toStop Point on Landings," to inform operators and pilots about the importance of establishing a CTS point; however, the director of operations was not aware of the concept of a CTS point during landing.

According to the pilot, during the landing roll, the airplane "began to drift sharply to the left." The pilot reported that, although there were no wind gusts reported, he felt as though a wind gust was pushing the airplane to the left. He attempted to maintain directional control with rudder pedal application, and he applied full right aileron. The airplane continued to drift to the left, and the pilot attempted to abort the landing by applying full throttle and 25° of flaps. He reported that the airplane continued to drift to the left and that he was not able to achieve sufficient airspeed to rotate. The airplane exited the runway, the pilot pulled the throttle to idle, and he applied the brakes to avoid obstacles. However, the airplane impacted the runway and taxiway signage and came to rest in a drainage culvert. The airplane sustained substantial damage to both wings. The published METAR for the accident airport reported that the wind was from 290° at 15 knots, and wind gusts exceeded 22 knots 1 hour before and 1 hour after the accident. The pilot landed the airplane on runway 20. The maximum demonstrated crosswind component for the airplane was 17 knots. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

The commercial pilot reported that he had completed several uneventful flights in the multiengine airplane earlier on the day of the accident. He subsequently took off for a return flight to his home airport. He reported that the en route portion of the flight was uneventful, and on final approach for the traffic pattern for landing, all instruments were indicating normal. He stated that the airplane landed "firmly," that the right wing dropped, and that the right engine propeller blades contacted the runway. He pulled back on the yoke, and the airplane became airborne again momentarily before settling back on the runway. The right main landing gear (MLG) collapsed, and the airplane then veered off the right side of the runway and struck a runway sign and weather antenna. Witness reports corroborated the pilot's report. Postaccident examination revealed that the right MLG actuator was fractured and that the landing gear was inside the wheel well, which likely resulted from the hard landing. The pilot reported that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. Based on the pilot and witness statements and the wreckage examination, it is likely that the pilot improperly flared the airplane, which resulted in the hard landing and the collapse of the MLG.

On December 15, 2015, at 5:23pm central standard time (CST), Southwest Airlines flight 31, a Boeing 737-300, N649SW, exited the taxiway while taxing to the gate and came to rest in a ditch at the Nashville International Airport (BNA), Nashville, Tennessee. Nine of the 138 passengers and crew onboard received minor injuries during the evacuation and the airplane was substantially damaged. The airplane was operating under the provisions of 14 Code of Federal Regulations Part 121 as a regularly scheduled passenger flight from William P. Hobby Airport (HOU), Houston, Texas. Weather was not a factor, light conditions were dark just after sunset. The airplane landed normally on runway 20R and exited at taxiway B2. The flight crew received and understood the taxi instructions to their assigned gate. As the crew proceeded along taxiway T3, the flight crew had difficulty locating taxiway T4 as the area was dark, and there was glare from the terminal lights ahead. The crew maneuvered the airplane along T3 and onto T4, and then turned back to the right on a general heading consistent with heading across the ramp toward the assigned gate. The flight crew could not see T4 or the grassy area because the taxiway lights were off and the glare from the terminal lights. As a result, the airplane left the pavement and came to rest in a drainage ditch resulting in substantial damage to airplane. The cabin crew initially attempted to keep the passengers seated, but after being unable to contact the flight crew due to the loud alarm on the flight deck, the cabin crew properly initiated and conducted an evacuation. As a result of past complaints regarding the brightness of the green taxiway centerline lights on taxiways H, J, L and T-6, BNA tower controllers routinely turned off the taxiway centerline lighting. Although the facility had not received any requests on the day of the accident, about 30 minutes prior to the event the tower controller in charge (CIC) turned off the centerline lights as a matter of routine. In doing so, the CIC inadvertently turned off the "TWY J & Apron 2" selector, which included the taxiway lights in the vicinity of the excursion. The airfield lighting panel screensaver feature prevented the tower controllers from having an immediate visual reference to the status of the airfield lighting.

Shortly after takeoff in day visual meteorological conditions, when the airplane was climbing through 3,000 ft mean sea level, a complete electrical failure occurred that affected electrical instrumentation and additional airplane equipment, including the landing gear. The pilot reported that he performed the electrical failure checklists and could not restore power. After additional troubleshooting with no success, he chose to divert to and land at another airport. While in the traffic pattern at his diversion airport, he attempted to lower the landing gear using the emergency landing gear extension procedures but could not confirm the landing gear were down and locked. Without any capability to communicate or confirmation that the landing gear were down, he decided to leave the airport traffic pattern and land on a nearby field to avoid airport traffic; the airplane sustained substantial damage to the fuselage, landing gear doors, engines, and propellers during the off-airport landing. The reason for the loss of electrical power could not be determined. Examination of the cockpit revealed that the landing gear's emergency engage handle, also known as the "J" handle, was not pulled up and turned, which was one of the steps listed in the airplane flight manual for the manual landing gear extension procedure. The "J" handle engages the clutch and allows for the handle to operate the landing gear chain. Without engaging the "J" handle, the landing gear handle pumping action would not have worked, which resulted in the gear-up landing.

According to the pilot's written statement he departed runway 05 and the airplane veered "sharply" to the right. The pilot assumed a failure of the right engine and turned to initiate a landing on runway 23. Seconds after the airplane touched down it began to veer to the left. The pilot applied power to the left engine and right rudder, but the airplane departed the left side of the runway, the right main and nose landing gear collapsed and the airplane came to rest resulting in substantial damage to the right wing. The pilot reported that he had failed to configure the rudder trim prior to takeoff and that there were no preimpact mechanical malfunctions or anomalies that would have precluded normal operation.

The instrument-rated private pilot was conducting a personal cross-country flight in the multiengine airplane under instrument flight rules (IFR). As the flight neared its destination, the controller issued clearance for a GPS approach, and, shortly thereafter, the pilot informed the controller that he needed to review the approach procedure before continuing the approach. The controller acknowledged, and, after the pilot reported that he was ready to proceed with the approach, the controller again issued clearance for the GPS approach. Radar data showed that, during the approach, the airplane tracked a course that was offset about 0.5 miles right of the final approach course until it was about 1 mile from the runway threshold. The airplane then turned left towards the threshold and descended to an altitude of about 145 ft above ground level over the runway threshold before the pilot performed a missed approach. It is likely that the pilot performed the missed approach because he was unable to align the airplane with the runway before it crossed the threshold. The controller provided radar vectors for the airplane to return to the approach course and cleared the airplane a third time for the GPS approach to the runway. Radar data showed that the airplane was established on the final approach course as it passed the initial approach fix; however, before it reached the final approach fix, its airspeed slowed to about 111 knots, and it began a left turn with a 25 degree bank angle. About 18 seconds later, while still in the turn, the airplane slowed to 108 knots and began descending rapidly. The airplane's rate of descent exceeded 10,000 feet per minute, and it impacted the ground about 9 miles from the destination airport. Examination of the accident site showed that the airplane was severely fragmented and fire damaged with debris scattered for about 450 feet. Postaccident examination of the wreckage did not reveal evidence of any preimpact failures; however, damage to the left engine indicated that it was not producing power at the time of the accident. The severity of impact and fire damage to the airplane and engine precluded determination of the reason for the loss of left engine power. Weather conditions present at the time of the accident were conducive to super cooled liquid water droplets, and the airplane likely encountered moderate or greater icing conditions. Several pilot reports (PIREPs) for moderate, light, trace, and negative icing were reported to air traffic control but were not distributed publicly into the national airspace system, and there was no airmen's meteorological information (AIRMET) issued for icing. However, the pilot received standard and abbreviated weather briefings for the flight, and his most recent weather briefing included three PIREPs for icing conditions in the area of the accident site. Given the weather information provided, the pilot should have known icing conditions were possible. Even so, the public distribution of additional PIREPs would have likely increased the weather situational awareness by the pilot, weather forecasters, and air traffic controllers. The airplane was equipped with deicing and anti-icing systems that included wing and empennage deice boots and engine inlet heaters. Due to impact damage to the cockpit, the positions of the switches for the ice protection systems at the time of the accident could not be determined. Although the airplane's airspeed of 108 knots when the steep descent began was above its published stall speed of 77 knots, both bank angle and ice accretion would have increased the stall speed. In addition, the published minimum control airspeed was 93 knots. It is likely that, after the airplane passed the initial approach fix, the left engine lost power, the airplane's airspeed began to decay, and the asymmetric thrust resulted in a left turn. As the airspeed continued to decay, it decreased below either stall speed or minimum control airspeed, and the airplane entered an uncontrolled descent.