roccoangelella/AeroGraph huggingface dataset:
The pilot of a powered glider reported that during the landing roll on a narrow grass airstrip, the glider veered to the left of centerline. He attempted to correct for the veer with right rudder input, but was unsuccessful. The left main landing gear traveled over a slope in the runway [crown for drainage purposes] and the left wing impacted corn stalks. The glider spun to the left and slid down the drainage area into the corn field. The glider sustained substantial damage to the fuselage.The pilot reported no preaccident mechanical malfunctions or failures with the powered glider that would have precluded normal operation.
The pilot stated that he hand-propped the engine, boarded the airplane, and began to taxi and that, shortly thereafter, the engine "sputtered and stalled." He then realized that he had left the fuel selector in the "off" position. He set the parking brake, turned the fuel on, exited the airplane, and hand-propped the engine again. The engine started and ran at a high rpm. The airplane moved forward and began to spin in circles. The pilot attempted to get back in the cockpit; however, the door had swung closed, and the airplane struck him, knocking him to the ground. The airplane spun a few more times before striking a hangar, which resulted in substantial damage to the right wing, and coming to a stop. Afterward, the pilot recalled that he had forgotten to retard the throttle before attempting the second engine start. The airplane was not equipped with an electric starter.
The pilot reported that he made an approach to a remote grass airstrip that resulted in the tailwheel-equipped airplane being too low to make the airstrip threshold. During the touchdown, the main landing gear impacted an embankment and collapsed, and the bottom of the fuselage impacted terrain. The airplane sustained substantial damage to the fuselage.The pilot reported that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.As a safety recommendation, the pilot reported to avoid landing at this particular area until more reconnaissance is conducted along with additional off airport operations practice. The Federal Aviation Administration has published the Airplane Flying Handbook FAA-H-8083-3A (2004). This handbook discusses a low final approach and states in part:When it is realized the runway will not be reached unless appropriate action is taken, power must be applied immediately to maintain the airspeed while the pitch attitude is raised to increase lift and stop the descent. When the proper approach path has been intercepted, the correct approach attitude should be reestablished and the power reduced and a stabilized approach maintained.
Before the accident flight, the airplane's brakes were replaced with a custom brake system. Testing of the brake system after installation resulted in a failure of the right master cylinder. The cylinder was disassembled and the O-ring was found cut. The mechanic could not find any reason for the cut O-ring, so the O-rings on both master cylinders were replaced. The next brake test resulted in a brake fluid boil, and the brake builder informed the mechanic to change the type of hydraulic fluid. A subsequent ground brake test produced "no issues or hesitation with the brakes at all," to include "a full pressure pedal push to simulate a full locked brake to pressure test [the] system prior to taxi test." A maintenance flight was then conducted, and, during landing, the airplane began to drift to the right. The commercial pilot applied the left brake; however, the brake failed and the pedal "went to the floor." The airplane departed the runway and collided with a wind sock structure. Postaccident examination revealed that the left brake master cylinder O-ring was cut; however, the reason for the cut could not be determined.After the accident, the mechanic contacted the master cylinder manufacturer for guidance. The company replaced the master cylinders with an upgraded model. The new cylinders were installed on the airplane and the mechanic, with guidance from the custom brake manufacturer, conducted more testing. A second airplane flew with the newer brake system without issue.
The commercial pilot reported that he made a normal approach and landing to an unimproved landing strip and that the left main landing gear (MLG) wheel assembly separated from the landing gear leg at the axle bolts during rollout. The gear leg then dug into the gravel landing surface, which resulted in a sudden left turn, ground loop, and subsequent substantial damage to the left wing, left aileron, and elevator. The pilot and the passenger stated that it did not feel as if the airplane hit anything during the landing rollout. The pilot also stated that the initiating event may have been a crosswind landing on a hard-surfaced runway with large tundra tires earlier in the week, during which he inadvertently "put a side load on the landing gear." Postaccident examination of the left MLG axle assembly and bolts revealed that the left axle had separated from the landing gear leg due to a rearward overload event. The initial separation was due to the shearing of the forward bolt threads by tensile forces on the bolts, which was followed by the bending deformation of the aft bolts, consistent with a fore-to-aft overload.
The private pilot stated that, shortly after takeoff and while 300 to 500 ft above ground level, the engine experienced a loss of power when he activated the flap switch. The pilot troubleshot the loss of power and attempted to restart the engine; the engine restarted momentarily, then lost power again. The pilot did not pull the boost cutoff control. During the emergency landing, the airplane collided with a barbed wire fence and impacted several trees. An electronic engine monitor provided data from the accident flight. There were several noticeable voids in the engine monitor data, indicative of electrical power interruptions to the device. The final electrical power interruption occurred about the time of the accident. The investigation was unable to determine a reason for the electrical power interruptions to the engine monitor other than the cycling of the avionics switch. The airplane's electrical system could not be functionally tested due to impact damage.Four engine test runs were conducted, revealing no anomalies. During the tests, the battery voltage displayed 13 to 15 volts, and the ammeter did not show a discharge. Examination of the airplane revealed that the aftermarket supercharger drive belt was improperly installed upside down. The fuel inlet screen contained a small amount of multicolor organic material similar to tree leaves. The presence of organic material did not adversely affect the engine test runs, and likely was the result of the impact with trees during the accident sequence. According to the emergency procedures provided by the supercharger manufacturer, the supercharged engine can be operated during a loss of electrical power by pulling the boost cutoff control. Pulling the boost cutoff control results in gravity-fed fuel supplying the engine at un-boosted manifold pressure and allows operation as a normally-aspirated engine. Further, if the boost cutoff control is not pulled when electrical power is lost, surging occurs as the carburetor bowl empties and refills and will continue as long as fuel is available in the fuel system. The surging stops when the boost cutoff control is pulled. It is likely that, had the pilot pulled the boost cutoff control, the engine would have stopped surging and Page 2 of 12 CEN16LA270engine power would have been restored. The pilot stated he was not trained in the operation of the supercharger; however, the airplane flight manual supplement contained information regarding supercharger operation and emergency procedures.
The student pilot reported that on the second landing during her first solo flight, the airplane porpoised. On the second bounce the nose wheel impacted first, which resulted in substantial damage to the firewall. The student pilot reported that she taxied the airplane to the tie down area without further incident. According to the student pilot there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.The Federal Aviation Administration has published the Airplane Flying Handbook FAA-H-8083-3A (2004). This handbook discusses porpoising and states in part:In a bounced landing that is improperly recovered, the airplane comes in nose first setting off a series of motions that imitate the jumps and dives of a porpoise—hence the name. The problem is improper airplane attitude at touchdown, sometimes caused by inattention, not knowing where the ground is, mistrimming or forcing the airplane onto the runway.Ground effect decreases elevator control effectiveness and increases the effort required to raise the nose. Not enough elevator or stabilator trim can result in a nose low contact with the runway and a porpoise develops.Porpoising can also be caused by improper airspeed control. Usually, if an approach is too fast, the airplane floats and the pilot tries to force it on the runway when the airplane still wants to fly. A gust of wind, a bump in the runway, or even a slight tug on the control wheel will send the air plane aloft again. The corrective action for a porpoise is the same as for a bounce and similarly depends on its severity. When it is very slight and there is no extreme change in the airplane's pitch attitude, a follow-up landing may be executed by applying sufficient power to cushion the subsequent touchdown, and smoothly adjusting the pitch to the proper touchdown attitude.Page 2 of 5 GAA16CA386
The private pilot stated that, during the landing roll in the tailwheel-equipped airplane, he started a right turn to exit the runway using a high-speed taxiway when the airplane had slowed to about 20 mph. During the exit, the airplane made an abrupt right turn that the pilot could not control with left rudder and brake. The left wheel axle fractured, followed by a collapse of the left landing gear leg, which resulted in substantial damage to the airplane. The reported wind was a left quartering tailwind of 4 knots. The pilot and passenger observed variable gusting wind immediately after the accident. Postaccident examination after recovery of the wreckage found that the tailwheel attachment bracket was fractured. An examination of the left main landing gear axle weld fracture with a scanning electron microscope (SEM) revealed features consistent with tensile overstress that would have occurred during the accident sequence. An examination of the airframe tailwheel mount fracture surface with a SEM revealed signatures consistent with overstress failure, and other fracture areas of widespread corrosion.Photographs taken before the airplane was removed from the runway showed the tailwheel assembly in its normal position, with no abnormalities visible. Also, during the recovery of the airplane, no tailwheel separation or abnormal function was observed. Based on the examinations of the fractured components, there is no evidence that the fracture of the tailwheel mount led to a displacement of the tailwheel assembly or a loss of control during the landing.Based upon the pilot and passenger's statements regarding wind at the accident site, it is possible that an unexpected gust of quartering tailwind initiated a loss of control, and the high groundspeed and heavy landing weight contributed to increased lateral loads on the left landing gear during the ground loop, which resulted in overload failures of the axle and tail bracket welds.Page 2 of 8 ANC16LA048
The private pilot was conducting touch-and-go landings in the homebuilt, tailwheel-equipped, experimental airplane. After a normal touchdown, the airplane veered to the left off the asphalt runway surface and ground looped as it departed the runway, which resulted in substantial damage to the fuselage and left wing. Postaccident examination revealed that the left main landing gear retaining mechanism was broken, but it was not clear if the damage occurred before or after the loss of control. The pilot, who was the builder of the airplane and had about 500 hours of flight time in the airplane, reported that he believed that the retaining mechanism could have broken upon landing and resulted in the ground loop. The winds were light and variable at the time of the accident. Because the damage to the landing gear retention mechanism could have occurred before or after the loss of control, the reason for the loss of control could not be determined.
The pilot of an airplane not equipped with radios or certified for flight into instrument meteorological conditions reported that during the initial climb, "I was in the fog and knew I had to get back down." The pilot further reported that he navigated the airplane to two other nearby airports with a non-aviation handheld global positioning system, but both airports were fogged in. After flying for about 30 minutes, the pilot reported that he was concerned with the fuel remaining, due to only taking off with about ½ full fuel tanks. He subsequently navigated back to the departure airport and saw the grass runway below him through a hole in the fog. The pilot reported that he "slipped it through" the hole, but his touchdown was about ¾ of the way down the wet grass runway. The pilot attempted to ground loop the airplane within the runway distance remaining, but the airplane continued straight and overran the runway, impacting a ditch and vegetation.The fuselage and both wings sustained substantial damage.     The pilot did not report any mechanical malfunctions or failures with the airplane that would have precluded normal operation. The pilot reported that he did not obtain a weather briefing prior to flight. He also reported that during preflight he observed "a little fog sneaking up over a nearby hill." The departure airport was not equipped with an automated weather observing station (AWOS), but an airport with an AWOS 10 nautical miles southwest at the time of departure reported the visibility at ¼ statute miles with fog, a cloud ceiling of 100 feet overcast, and a temperature of 68 degrees Fahrenheit (20 Celsius) and dew point of 68 degrees Fahrenheit (20 Celsius). The Federal Aviation Administration Pilot's Handbook of Aeronautical Knowledge (PHAK) in part states: "When the temperature of the air is reduced to the dew point, the air is completely saturated and moisture begins to condense out of the air in the form of fog, dew, frost, clouds, rain, or snow."Page 2 of 7 GAA16CA383
The private pilot reported that during a local flight in the aerobatic biplane, he performed an aerobatic flight maneuver about 2,000 feet above ground level. He reported that he performed a left wing over, the airplane entered an unintentional spin and he recovered from the spin too low to the ground. The airplane impacted trees and came to rest upright, but sustained substantial damage to both wings, fuselage and empennage.The pilot reported that there were no mechanical malfunctions or anomalies with the airplane during the flight that would have prevented normal flight operations.
The private pilot of a red and white Cessna was conducting a personal local flight. The pilot reported that, about 10 minutes into the flight, the pilot of an unknown aircraft contacted him over the airport's common traffic advisory frequency (CTAF) and stated "we almost got you." However, the pilot later reported that he had not heard any previous communications from other aircraft in the local area on the CTAF, that he did not observe any aircraft nearby at the time of the radio call, and that he did not feel any sudden movement of the airplane, so he chose to continue the flight. He landed about 40 minutes later at his originating airport. Postaccident examination of the airplane revealed substantial damage to the rudder, which displayed a lateral tear and a blue paint mark at the trailing edge of the control surface. Although the pilot did not feel any sudden movement of the airplane, the blue paint mark and rudder damage indicates that his airplane's rudder was contacted by another object during the flight.The unknown pilot's statement, "we almost got you," suggests that the unknown pilot also might not have been aware that the two aircraft actually collided; however, this could not be confirmed because the pilot and other aircraft were never identified.
The private pilot was conducting a local personal flight, which was the airplane's first flight following its annual inspection. The pilot reported that, while on the downwind leg, he reduced power for landing and that the engine then lost power. During the subsequent forced landing, the airplane encountered a crosswind gust and then bounced twice, which caused substantial firewall damage. An examination of the carburetor revealed no anomalies. The weather conditions at the time of the accident were conducive to the accumulation of serious carburetor icing at descent power settings. It is likely that the engine power lost power due to carburetor icing.
The private pilot/co-owner of the airplane departed on a roundtrip flight with the right main fuel tank full and the left main fuel tank "down about three gallons." He stated that, based on his preflight performance planning and visual inspection of the fuel supply, the fuel in the main tanks would be sufficient for the flight. The outbound leg was conducted with the fuel selector on the right main tank, and the return leg was flown with the fuel selector on the left main tank. Shortly after being cleared for landing near the end of the return leg, the airplane experienced a total loss of engine power, and descended into wooded terrain about 1 mile from the airport.Postaccident examination of the wreckage revealed that the right main fuel tank contained 2 gallons of fuel, that the left main tank was empty, and that both 15-gallon auxiliary fuel tanks were full. The engine was subsequently placed in a test cell where it started immediately, accelerated smoothly, and ran continuously at all power settings. The co-owner of the airplane stated that the left fuel tank leaked when the tank was full and that they mitigated the problem by not completely filling the left main fuel tank. The pilot likely mis-estimated the fuel available in the tanks during his preflight visual inspection, and it is likely that fuel leaked from the left tank during the flight, further reducing the available fuel quantity. These factors resulted in a loss of engine power consistent with fuel starvation.
The pilot of a tailwheel equipped airplane reported that due to the tall trees that surrounded the airport he elected to land to the north with a tailwind because of "less tree obstacles". He further reported that the airplane "touched down too far down the runway". He attempted to stop the airplane from over running the runway, but was unsuccessful. The airplane over ran the runway, impacted a grass berm, and nosed over.The airplane sustained substantial damage to the empennage. According to the pilot there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The Federal Aviation Administration has published the Advisory Circular (AC) 91-79A. This AC discusses the hazards associated with runway overruns and the effect of a tailwind on landing distance and states in part:The pilot must be aware of airspeed during the approach and of the targeted reference landing airspeed (VREF)/airspeed, plus wind gust adjustments, over the runway threshold. An excessive approach speed may result in an excessive speed over the runway's threshold, which may result in landing beyond the intended touchdown point as well as a higher speed from which the pilot must bring the airplane to a stop.The effect of a tailwind on landing distance is significant and is a factor in determining the landing distance required. Given the airplane will land at a particular airspeed, independent of the wind, the principal effect of a tailwind on operational landing distance is the change in the ground speed at which the airplane touches down.Page 2 of 6 GAA16CA382
The commercial pilot was taking off in the light sport aircraft for a local personal flight. The pilot reported that, while attempting to take off from the 4,799-ft-long runway, he noticed a lower-than-normal engine rpm and that the takeoff roll was significantly longer. Despite the extended takeoff roll and low engine rpm, the pilot chose to continue the takeoff. The airplane lifted off and slowly climbed to about 200 ft above ground level. Due to concerns about rising terrain, the pilot chose to make a forced landing, during which the airplane hit power lines. The airplane then skipped across a road and nosed over. Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures. Carburetor icing was likely not a factor given the environmental conditions at the time of the accident and the pilot's report of a short taxi time.
The sport pilot was conducting a local flight in the gyroplane that he and his wife had built. Witnesses saw the gyroplane start a turn, the nose of the gyroplane pitch up, and then the gyroplane descend and impact the ground. A postimpact fire ensued and destroyed the gyroplane. A postaccident examination of the airframe and engine did not reveal any mechanical anomalies that would have precluded normal operation; however, the examination was limited by fragmentation due to impact damage and heat damage due to the postimpact fire.The pilot had an undiagnosed adrenal tumor and was being treated for hypertension, depression, and chronic pain. However, it is unlikely that any of these conditions or treatments contributed to the abrupt loss of control in this accident. The reason for the sudden pitch up and then descent and impact with terrain could not be determined during the investigation.
The pilot of the tailwheel equipped airplane reported that during the takeoff roll from a grass airstrip, the airplane straddled an irrigation pipe on the east side to avoid a dip in the middle of the airstrip, impacted a sprinkler, and he lost directional control. The pilot further reported that the airplane veered left and impacted a fence, which resulted in a nose over and substantial damage to the left wing, empennage, and fuselage.The pilot reported that there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.
The private pilot was conducting a cross-country, personal flight in the experimental, amateur-built, tailwheel-equipped airplane. The pilot reported that, while slowing the airplane after a normal three-point landing in a calm wind, the airplane began swerving. The airplane then departed the right side of the runway and ground looped. Examination of the wreckage revealed that the left landing gear leg had separated. Metallurgical examination of the fractured landing gear leg surface revealed a small thumbnail-like fatigue region, followed by an overstress region. A previous owner had assembled the airplane from a kit about 32 years before the accident, and it had accumulated about 875 total hours of operation. The builder did not use the stock bungie landing gear that were included with the kit. Rather, to reduce drag, he designed and constructed his own round, tapered rod landing gear. It is likely that the homemade, custom-built landing gear leg could not support the same loading as the stock bungie landing gear, which resulted in fatigue over a period of time and the gear leg's subsequent failure.