roccoangelella/AeroGraph huggingface dataset:
During the approach, the pilot stated that he extended the landing gear and he received a down-and-locked green light indication. He also stated that he visually verified that the landing gear was extended. The touchdown was normal, but firm, and shortly thereafter, the main landing gear collapsed. The airplane veered off the runway about midfield and came to rest in the area between the taxiway and runway. A postaccident examination of the airplane’s landing gear system revealed no anomalies that would have prevented normal operation of the landing gear. With the airplane on jacks, several cycles of the landing gear were accomplished and the landing gear warning horn audio and indicator lights operated properly. Additionally, the landing gear circuit breakers remained closed during the examination and the hydraulic system fluid level was full.According to witnesses, who were working on the airport ramp, the nose gear appeared to be down and locked but the main landing gear was only partially extended for the approach and landing. It is likely that the pilot did not position the landing gear to the down position in a timely manner and it was not yet in the fully extended position when the airplane touched down.The results from the airplane examination, witnesses’ observations, and the outer edge markings on the main tires, were all consistent with the main landing gear not being fully extended and locked during landing.
The pilot reported that he planned to refuel the skydiving jump airplane after his third flight of skydivers and experienced about 10 minutes of loading delays with the third flight of skydivers. Then, while climbing, he was “delayed a few minutes” because of traffic in the area. He stated that he was not sure when the low fuel light illuminated, but that on his descent back toward the airport after releasing the third load of skydivers, the red “Reservoir Fuel Low” annunciator illuminated. About 8,000 ft mean sea level, the engine lost all power due to fuel exhaustion. Subsequently, the pilot made an emergency landing at the airport; however, the airplane was “fast and floated.” The airplane touched down midfield, departed the end of the runway, and encountered a tree line, substantially damaging the left wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. After the accident, the pilot stated he “believe[d] the aircraft ran out of fuel due to several unforeseen and unplanned delays.”
The pilot stated that during a nonprecision instrument approach to the destination airport, he applied full engine power when he noticed that the airplane airspeed was decreasing. He realized that the engine lost power and was unsuccessful in attempts at regaining engine power. He performed a forced landing on a pasture during which the airplane sustained substantial damage that included damage to the right wing. A postaccident examination of the wreckage revealed streaks fuel on the left side of the engine cowling. An examination of the engine revealed the fuel control assembly was leaking at the mixture control shaft’s O-ring. The O-ring was intact and did not exhibit separation. However, the outside diameter of the O-ring was less than the diameter of the mixture control shaft consistent with wear. A leak within the fuel control assembly would have allowed air to enter/fuel to exit the assembly resulting in improper fuel metering and a loss of engine power. No other mechanical anomalies were noted with the airframe and engine that would have precluded normal operations.Maintenance records showed that the last overhaul of the fuel control assembly was performed during an engine overhaul in 1996. There were no subsequent records or evidence that indicated the assembly was overhauled after 1996. The engine manufacturer’s recommended time between overhaul (TBO) was 12 years. The engine manufacturer’s standard practice manual stated that engine accessories must be overhauled at the time of engine overhaul. The engine and fuel control assembly exceeded the engine manufacturer’s recommended TBO.Page 2 of 7 CEN22LA233
The pilot reported that he was attempting a takeoff in a right crosswind. About 25 to 30 ft above the ground, the airplane banked left about 60°, and the left wingtip struck the runway. The airplane then landed hard, slid off the left side of the runway and came to rest upright, oriented opposite of the takeoff direction. The pilot added that there were no preimpact mechanical malfunctions with the airplane. A postaccident examination revealed substantial damage to the left wing and fuselage.
The pilots were performing skydiving flights while the right-seated pilot was training the left-seated pilot on the operation. The pilots completed six flights without incident and completed the drop of the skydivers on the accident flight normally. The right-seated pilot could not completely recollect the minutes leading up to the accident due to his injuries. He did recall that airplane was descending as expected with the power at idle. The recorded ADS-B data revealed that after turning onto final approach, the airplane then completed a right 360° turn presumably because the altitude was too high. The right-seated pilot attempted to increase the power by slightly nudging the throttle forward and thought the engine power did not increase as expected. A performance study revealed that in the last 70 seconds of recorded data, the airplane underwent a series of speed and thrust oscillations consistent with a pilot increasing and then decreasing the power lever. The right seat pilot recalls aiming for an open dirt field and observing a berm in the immediate flight path. In an effort to avoid the berm, he maneuvered the airplane into a right turn. The airplane landed short of the runway, resulting in a collision with the berm.The engine was producing power at the time of impact. Postaccident examination of the airplane revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The right-seated pilot was in the process of training the left-seated pilot and stated that he took over the controls during the final approach. It is unknown when he took over the controls, so it is unknown which pilot was at the controls during the speed oscillations. The right-seated pilot likely took over the controls too late and the airplane impacted the terrain. The left-seated pilot’s ability to hear the changes in engine power might have been hindered because she was listening to music through her headset at an elevated decibel level. The airplane was modified by a Supplemental Type Certificate that replaces the original Pratt & Whitney PT-6 turbine engine with a Honeywell TPE331 turbine engine. The TPE331 engine’s characteristics are Page 2 of 12 WPR22FA197such that if the airplane is on final approach with the power near idle, the throttle sensitivity (change in thrust per unit of power lever movement) increases around the transition between the propeller-governing and underspeed-governing modes of the engine, which corresponds to a zero-thrust condition. Near this transition point, small movements of the power lever (about ¼  to ½ inch of deflection) can result in relatively large thrust changes that can surprise pilots inexperienced with this behavior and result in pilot-induced oscillations (PIO). Given the thrust oscillations observed shortly before the end of the ADS-B data, it is likely that the left-seated pilot was at the controls and experienced such a PIO on a short final approach to land.
The student pilot, and his flight instructor, were on a local training flight practicing maneuvers. Shortly after the student transferred fuel from the wing tanks to the main fuel tank, the engine lost all power. Unable to restart the engine, they performed a forced landing to a wheat field. During the landing, the airplane nosed over and came to rest inverted.Examination of the airplane revealed water and corrosion present in the fuel gascolator. The night before the accident the airplane was parked outside, and it had rained. The student pilot reported that as part of his preflight, he drained the sump at the bottom of the engine but did not drain the wing fuel sumps. The flight instructor reported that he was not familiar with the airplane and the location of the fuel sumps.
The flight instructor and pilot observed the engine power decrease about 200 rpm on two occasions while en route. The pilot flew an approach and then a go-around due to excess airspeed during the approach. When the throttle and carburetor heat controls were fully advanced, the engine power only increased to about 2,000 rpm. The flight instructor attempted to increase engine power without success. During the forced landing to a field the airplane hit a tree, which resulted in substantial damage to the right wing. Examination of the engine revealed normal engine continuity and compression was confirmed on all 4 cylinders. Several hold down studs on the No. 1 cylinder were fractured and their separated pieces were found in the bottom of the cowling. No other anomalies were observed that would have precluded normal engine operation. No impact damage occurred in the vicinity of the engine and investigators could not determine when these studs separated; however, it is unlikely that the separated studs resulted in the slight loss of engine power noted by the pilot and flight instructor.The weather conditions at the time of the accident were conducive to serious carburetor icing at glide power. The flight instructor recalled pulling the carburetor heat lever out during the approach, therefore, it is unlikely that carburetor icing resulted in the loss of engine power.Investigators were not able to determine the reason for the loss of engine power.
Two pilots were conducting a local flight to practice basic agricultural flight maneuvers. A witness observed the airplane enter a right turn at low altitude, during which the right wing dropped, and the airplane nosed down toward terrain and disappeared from his view. The airplane impacted terrain in a nose- and left-wing-low attitude in a field. The airplane sustained substantial damage to the fuselage, wings, and empennage.A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The airplane damage was consistent with a near-vertical descent, indicative of an aerodynamic stall. It could not be determined which of the two pilots was flying the airplane at the time of the accident. The circumstances of the accident are consistent with the pilots’ failure to maintain sufficient airspeed while maneuvering, which resulted in an exceedance of the airplane’s critical angle of attack and an aerodynamic stall.
The two pilots were practicing pinnacle landings and takeoffs on a hilltop. The pilot in command (PIC) in the right seat was performing a takeoff when the helicopter encountered a wind gust that resulted in a right yaw. The PIC applied left anti-torque pedal to arrest the yaw when his left heel slipped off the front end of the footrest.  His foot became wedged between the pedal and footrest, which resulted in an uncontrollable left spin. The PIC reduced collective, and the helicopter landed hard. The landing skids collapsed on landing, substantially damaging the fuselage and tail. The pilot reported that there were no mechanical failures or malfunctions with the helicopter that would have precluded normal operation.
The pilot of the experimental, amateur-built airplane reported that the airplane contained about 13 gallons of fuel prior to takeoff for a 1-hour local flight. After flying for about 30 minutes, the pilot switched from the left to the right fuel tank. Shortly thereafter, the engine lost power. The pilot thought he accidently ran out of fuel; however, the header fuel tank gauge indicated a full tank. Due to the airplane’s low altitude at the time of the engine power loss, the pilot executed a forced landing to a mowed wheat field which was surrounded by a low-profile fence. During the landing, the airplane contacted the fence and nosed over. The airplane sustained substantial damage to both wings and rudder. The airplane’s fuel system consisted of a fuel tank in each wing that gravity fed to a header tank. The header tank contained two internal fuel pumps that delivered fuel to the engine driven fuel pump. The header tank was equipped with a “Motor Meter Racing Fuel Level” gauge.A postaccident examination and a functional test of the engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. A functional test of the fuel gauge determined the gauge was inoperative.
The pilot, who was the builder of the experimental, amateur-built airplane, reported that shortly after takeoff the engine surged rapidly three times and then lost total power. The pilot turned the airplane back toward the airport to try to land on the runway. While maneuvering toward the airport, the pilot attempted to restore engine power, but was not successful. Unable make the runway, the pilot performed a forced landing to a rough field, during which the airplane sustained substantial damage to the fuselage and wings.A postaccident examination of the engine found that the bearings connecting the piston arms to the crankshaft were seized and displayed signatures consistent with a lack of oil lubrication and cooling. Reviewed data stored in the electronic flight instrument system did not provide indications of an impending oil system malfunction. The pilot stated that he purchased the engine as a “firewall forward” package and speculated that the engine could have benefitted from the installation of a secondary oil cooler.
The pilot reported that during the landing the airplane encountered a downdraft. The airplane bounced twice and jerked to the left before the pilot attempted to abort the landing. The airplane departed the runway to the left and then returned back to the runway where the left main landing gear separated from the fuselage. The airplane came to rest on its right main wheel, tail wheel, and left wing, which resulted in substantial damage to the left wing spar.The left landing gear damage was consistent with impact and overload separation. A review of the maintenance records did not reveal any maintenance to the left landing gear attach point.  Examination of the airplane did not reveal any evidence of a pre-impact anomaly that would have precluded normal operations. It is likely that the landing gear separated from the airplane due to impact forces during the landing.
The accident pilot was a partial owner of the accident airplane, which had not flown for several months until he attempted to fly the airplane about 2 weeks before the accident. During this previous flight the pilot and his student were forced to abort two takeoff attempts after the airplane failed to climb. The pilot and pilot-rated passenger, who was also a flight instructor, had planned to fly the airplane on the day of the accident to troubleshoot the performance deficiency. During takeoff on the accident flight, the airplane reached an intermediate altitude before it started to settle momentarily. The airplane then continued to climb to a peak altitude of about 100 ft above ground level and then it started a right turn that progressively became steeper. Subsequently, the airplane impacted the ground in a nose-down attitude.An analysis of the engine harmonics during takeoff suggested that the engine may have encountered anomalies when the airplane began its right turn, but this could not be substantiated as postaccident examination of the airframe and engine did not reveal any preimpact mechanical anomalies. The fuel selector was found between the RIGHT tank detent and the OFF position at the accident site. During the flight 2 weeks earlier the accident the pilot had placed the handle in a similar position before takeoff. As there were no preimpact mechanical anomalies with the engine, it is likely that the improper placement of the fuel selector in the OFF position during takeoff resulted in fuel starvation and a partial loss of engine power. Performance computations indicated that the airplane was capable of a successful takeoff as it was below its maximum gross weight. The airplane’s center of gravity (CG) was nose-heavy, which likely would have resulted in difficulty in lifting the nose during takeoff and during Page 2 of 13 WPR22FA196reduced power situations. However, this CG condition is only likely to have affected takeoff and likely did not contribute to the accident. Recorded data suggests the airplane entered an accelerated stall in the turn when it exceeded the critical angle of attack without maintaining adequate airspeed. The investigation was unable to determine if the pilot-rated passenger was aware of the airplane’s takeoff issues 2 weeks before the accident. It is also unclear who was piloting the airplane in its final moments; however, the pilot was likely flying at the time considering he was a part owner in the airplane and given his motivation to troubleshoot the performance deficiency. While cardiovascular conditions placed the pilot at an increased risk for a sudden cardiac event, operational evidence does not suggest that this occurred and was likely not a factor in this accident.
The pilot was performing aerobatic maneuvers over desert terrain. A witness reported that the airplane entered a “barrel roll climb,” followed by a “stall.” The airplane then entered an inverted, nose-down “dive” before rolling upright, but continuing its nose-down descent. The witness then lost sight of the airplane behind trees. The airplane impacted terrain in a nose-down attitude and was significantly fragmented. Postaccident examination of the airplane and engine did not reveal any preimpact mechanical anomalies. Flight tracking data ended about 1 mile from the accident site at an altitude about 2,725 ft above ground level (agl). Given the available information, it could not be determined whether the pilot lost control of the airplane and was unable to recover before impacting terrain, or entered an intentional aerobatic maneuver with insufficient altitude.
The pilot was making an approach from the southeast to land the hot air balloon on a road that paralleled railroad tracks. A freight train was traveling northbound on the tracks at the same time. The balloon initially touched down in a grassy area east of the road, between the road and the railroad tracks. The balloon skipped normally and stopped near the railroad tracks. The balloon envelope dipped as a result of being slightly deflated for the landing and caught on one of the uprights of an empty lumber car as it passed, which lifted the balloon off the ground and dragged it. As the balloon was dragged, the uprights, envelope, burners, and fuel lines separated from the basket and the pilot and passengers were ejected. The engineer in the engine cab immediately stopped the train. The basket came to rest inverted along the east side of the railroad tracks. The envelope climbed to 200 ft. and drifted north until it cooled and came to rest on the road, about 80 ft from the basket. The pilot misjudged the landing, which placed him too close to the railroad tracks and resulted in the balloon’s envelope being caught and the balloon being dragged by the freight train as it went by.
The pilot reported that on final approach, he “started the flare too late,” which resulted in a “high bounce.” He attempted to recover, however the airplane “bounce[d]” again. The pilot initiated a go around, but with the “high angle of attack” of the airplane, he “lost control.” The airplane veered off the side of the runway and impacted a ditch, which sheared off the main landing gear, and resulted in substantial damage to the fuselage.  The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.
The aerial application airplane was loaded with chemical for application on a rice field. Immediately after the takeoff from the private airstrip, the pilot heard a “loud pop” noise from the turboprop engine, and he observed flames emit from the left side of the airplane. During the forced landing, the pilot reported that it felt like there was a “slight recovery” of engine power, but then the engine ceased producing power. During the forced landing, the airplane nosed over and came to rest inverted, resulting in  substantial damage to the left wing, the fuselage, and the empennage.Examination of the airframe revealed foreign object debris (FOD) between the airframe fuel filter pleats and in the fuel filter bowl. Examination of the engine revealed contamination of the engine fuel filter and various fuel wetted accessories. The engine exhibited rotational contact signatures on the compressor turbine and the power turbine components consistent with the engine producing power at the time of impact; however, the engine power output at the time of impact could not be determined. Marks on the piston, cylinder, and blade damage indicated the propeller was operating at low blade angles with low or no power at impact. Chemical testing of the FOD samples from the airframe and the engine revealed a composition consistent with an unknown fertilizer-type material.A review of the airplane’s maintenance records revealed that the airplane was flown about 44 hours past the manufacturer’s required fuel filter inspection interval.It is likely that contaminated fuel obstructed the engine fuel filter and was injected into the engine, which resulted in a partial loss of engine power. The source of the FOD and how it entered the fuel tanks could not be determined based on the available information. It is Page 2 of 8 CEN22LA228possible that, had the operator completed the airframe fuel filter inspection within the required interval, the contamination of the filter may have been identified.
According to the pilot while approaching the destination airport, the engine did not respond when he advanced the throttle. He also noted that the throttle felt “loose” and further described that the engine was still running, but that the rpm would not change. There was not sufficient engine power being produced in order for the airplane to reach the destination airport, so the pilot elected to perform an off-airport landing to a golf course. The airplane was substantially damaged during the landing, and the pilot and passenger were seriously injured. A postaccident examination of the engine found that the engine’s controls were damaged during the accident sequence and had separated from the engine. Additionally, the throttle arm was found loosely attached to the shaft at the throttle body. The nut needed to be tightened by 1/8-turn in order to fully engage. No other anomalies were noted during the examination that would have precluded normal operation of the engine. Review of the airplane’s maintenance records revealed that the engine controls had been inspected and lubricated about 7 months and 37 flight hours before the accident, with no subsequent maintenance to those components noted. Based on the pilot’s description that the engine did not respond to throttle changes and that it felt “loose,” as well as the finding that the throttle arm was found loosely attached to the throttle shaft, it is likely that the loosening of the securing nut resulted in the pilot’s inability to control the engine, and the subsequent forced landing.