N646UPiper Aircraft PA-46-701TP · 2025

On November 24, 2025, at 1529 Pacific daylight time, a Piper Aircraft Inc. PA-46-701TP (Fury), N646U, was substantially damaged when it was involved in an accident in Provo, Utah. The pilot was seriously injured and the three passengers sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight.

The pilot reported that he and the passengers had flown into Provo earlier in the day, and that the accident flight was destined to return to their home base in Van Nuys, California. The pilot recalled that he performed his normal takeoff procedure by configuring the autopilot to hold the runway heading, setting the climb in the flight management system (FMS) to an airspeed of about 125 kts with an altitude of 9,000 ft selected. He initiated the takeoff using the autothrottle button in takeoff mode. He reported the airplane departed normally and he subsequently retracted the landing gear. At about 500 to 600 feet above ground level (agl), he engaged the autopilot and a few seconds later, the airplane stopped climbing, and then began to descend. He checked the configuration and then disconnected the autothrottle and the autopilot.

The pilot further stated that when the airplane reached about 7,000 ft msl, the control yoke became very difficult to move and he observed that the pitch trim indication showed a full nose-up position. He attempted to move the trim wheel, but was unable to move it from the up stop. He asked the right-seated passenger to roll the trim wheel toward a neutral indication, but the pilot stated there was no effect on the control forces or the airplane’s nose-up tendency. The pilot held both hands on the yoke to hold the pitch attitude down in order to maintain level flight or descend. He stated the control pressure required to keep the nose from rising was extreme and unlike anything he had experienced. He stated he believed the trim was stuck in the full nose-up position even when the indicator later showed it to be near neutral.

The pilot reported that he relayed to air traffic control that he wanted to return to land at the departure airport and while maneuvering back he continued to exert high forward yoke forces to keep the airplane from pitching up. He reported difficulty slowing the airplane and attempted to locate and pull the appropriate circuit breaker, but could not reach it while maintaining forward pressure. He aligned the airplane for the approach to the runway with minimal configuration changes and targeted an airspeed of about 110 to 115 knots prior to touchdown. He stated that even on short final, he maintained two hands on the yoke and used a knee to keep the nose down. On touchdown, the pilot briefly relaxed his grip and the airplane immediately pitched up and became airborne again, then descended back to the runway. The airplane erupted in flames after it came to rest.

The airplane was equipped with a Garmin G3000 avionics suite with a GFC 700 digital autopilot, and a HALO autothrottle. According to the airplane’s Pilot Operating Handbook (POH), when the autothrottle is engaged, the system limits autothrottle operation to within the approved speed envelope of the airplane. Specifically, the autothrottle will automatically limit the airplane’s speed to the current configuration speed limitation regardless of the power or speeds selected by the pilot. When the autothrottle is not engaged, the system continuously monitors for overspeed and underspeed conditions, independent of flight director or autopilot modes, as long as the Electronic Stability and Protection (ESP) is active. If the airplane accelerates beyond the current configuration speed limit, the autothrottle engages and decreases power to prevent an overspeed condition; the pilot would receive an annunciation of “MAX SPD” as well as “Airspeed” and “Engaging Autothrottle” aural alerts. As the speed decreases below the limit, autothrottle disengages, an “Autothrottle” aural alert is played, and power remains where it was last set by the MAX SPD commands.

A preliminary review of the downloaded Garmin data was performed by the airplane manufacturer representatives. The data disclosed that while the airplane was at the hold-short threshold for runway 13, the autopilot was configured laterally in the heading-hold mode and then while taxiing to the runway centerline, the autopilot vertical mode was configured to flight level change (FLC) pitch-for-speed mode. As the airplane was on the centerline, the autothrottle was engaged as the pilot initiated the takeoff. The airplane lifted off at 1518:53, as indicated by the transition of the weight-on-wheels parameter to an airborne state. The landing gear retracted several seconds later and the flaps remained at the takeoff setting of 15°.

At 1519:11, as the airplane climbed to about 275 ft agl, the autopilot was activated and simultaneously the autopilot vertical mode changed from FLC to altitude hold mode. Beginning at 1519:26, the airplane entered a brief descent of approximately 133 ft with both the autopilot and autothrottle engaged, with the vertical mode remaining in FLC. (See Figure 1). During this descent, the airspeed appeared to exceed the Maximum Flap Extended Speed (Vfe) at 15° flaps (147 kt indicated airspeed (KIAS)). A reduction in engine torque occurred at 1519:41 with the autothrottle still engaged.

Figure 1: Autopilot configurations during the flight

The autothrottle disconnected at 1519:56, followed by activation of the autothrottle in ESP mode at 1520:02. The autothrottle engaged at 1520:04, consistent with protection that prevented an exceedance of the flap-extended airspeed limitation. Multiple autothrottle state changes occurred during the flap overspeed condition, consistent with manual disconnection attempts followed by automatic re-engagement as the airplane continued to exceed the 147 kts Vfe. (See Figure 2). The vertical mode changed from FLC to pitch mode at 1520:12 and from pitch to vertical speed mode at 1520:44.

Figure 2: Autothrottle configurations and airspeeds during flight

At 1521:28, altitude data showed the airplane entering a climb with the autopilot still engaged. Pitch trim values increased in the nose-up direction. There was an overtorque at 1521:08 and then again at 1521:55. The airplane’s pitch attitude increased from -1.1° to +10.7° over a 23.6-second interval, reaching the maximum value at 1521:51. A full extension and retraction of the landing gear occurred at 1521:35. A pitch oscillation of approximately 4° occurred at 1521:55, and the autothrottle was activated simultaneously. Pitch trim reached its maximum nose-up setting at 1522:11 and remained around there until 1524:04, at which point it transitioned to the nose-down position. Autothrottle was activated at 1523:39, and the flaps were retracted from 15° to the UP position at 1523:53. The vertical mode changed from vertical speed to pitch mode at 1524:15, then reverted back to vertical speed 2.6 seconds later. The airplane reached its maximum altitude of about 3,280 ft agl at 1524:18.

At 1525:16, the vertical mode again changed briefly from vertical speed to pitch mode before returning to vertical speed. Another brief pitch mode transition occurred at 1527:35 before the system returned to vertical speed. Pitch trim reached a neutral value at 1527:30. The pilot selected the landing gear down at 1528:01 at an indicated airspeed of 204 kts, well above the landing-gear-extended limit of 170 kts. Autothrottle was activated at 1528:03, accompanied by multiple state changes as the airspeed gradually decayed. The pitch trim moved in the nose-up direction following gear extension. The vertical mode again transitioned from vertical speed to pitch mode at 1528:10 and returned to vertical speed shortly thereafter.

The descent for landing began at 1528:18. The autopilot disconnected at 1528:40 at an altitude of 83 ft agl. A pitch oscillation developed immediately following the disconnect, with a maximum recorded peak-to-peak amplitude of approximately 12.9° during a 1.8-second period. When the airplane’s pitch attitude reached -4.9°, wheel-speed sensors on both main landing gears registered simultaneous spikes, and the left main weight-on-wheels parameter briefly indicated ground contact. The nose-gear weight-on-wheels parameter remained in the airborne state until 1536:41.

The airplane was recovered for a future examination.