Amateur-built LANCAIR IVP N724HP accident near Hartsville, South Carolina

Probable cause

Failure of the flying pilot to maintain control of the airplane while maneuvering at a low altitude, which resulted in the airplane exceeding its critical angle-of-attack and experiencing an aerodynamic stall. Contributing to the accident were the pilot/owner's decision to transfer physical control of the airplane during an inflight emergency to pilots with no previous experience in the accident airplane make and model and the failure of the landing gear actuation mechanism for reasons that could not be determined due to impact and postcrash fire damage.

NTSB analysis

Witnesses reported that the pilot/owner/builder of the experimental, amateur-built, turbine-engine-powered airplane had been troubleshooting the airplane's landing gear and electrical system on the day of the accident. After working on the airplane, the pilot/owner made an uneventful flight. Later that day, the pilot/owner departed on the accident flight with two other certificated pilots aboard. About 40 minutes later, relatives of the pilot/owner received text messages from him stating that the airplane's landing gear would not extend and that they should ask for emergency services to be available at a nearby airport. About the same time, witnesses observed the airplane flying over the runway at that airport at an altitude about 600 ft above the ground. The airplane then banked steeply left, pitched upward to an angle of about 25 degrees, and then descended in a nose-high pitch attitude to ground impact. This maneuvering was consistent with an inflight loss of control and subsequent aerodynamic stall/mush.

The airplane was almost entirely consumed by the subsequent post-impact fire. Postaccident examination of the wreckage revealed no evidence of any preimpact mechanical failures of the flight control system or the engine. The nose landing gear was retracted, and the left and right main landing gear were partially extended. The seat cushion for the right rear seat was displaced from its normal mounting position, and an access panel that was located beneath the seat and allowed access to the main landing gear actuators had been removed. Despite the fire-related damage to the hydraulic system, which was used for extension and retraction of the landing gear, the hydraulic reservoir remained intact and contained only a trace amount of hydraulic fluid. Given that both the primary and emergency landing gear extension mechanisms relied on the presence of hydraulic fluid for proper operation, it is possible that a lack of available fluid precipitated the pilot's inability to extend the landing gear as reported in his text messages. However, due to the extent of damage to the remainder of the hydraulic system, a definitive cause for the failure of the landing gear to extend could not be determined.

Examination of the wreckage also revealed that at the time of ground impact, the pilot/owner of the airplane was seated in the left rear seat, while the other two pilots were seated in the two front seats. It could not be determined which of the other pilots was flying the airplane when the loss of control occurred, and the seating positions of each occupant at the beginning of the flight are unknown. However, as neither of the other pilots had any flight experience in the accident airplane make and model, it is likely that the pilot/owner was in one of the front seats when the flight began and climbed into the rear seat during the flight when the landing gear would not extend in order to access the landing gear actuators.

Review of the airplane's maintenance records revealed no entries documenting that any of the required inspections or maintenance had been completed in the decade preceding the accident. Additionally, the maintenance records did not document repairs and modifications that had been performed on the airplane following a previous accident during which the airplane was substantially damaged.

Text from the NTSB. Open the NTSB docket for ERA14FA144 for the full record.