2 fatalities

2019-05-22: Cessna 550 Citation II (N311G) — Private United States of America — Indianapolis-Regional, United States of America

Indianapolis-Regional, United States of AmericaTakeoff (climb)

On May 22, 2019, a Cessna 550 Citation II (registration N311G) operated by Private United States of America was involved in an aviation accident near Indianapolis-Regional, United States of America during takeoff. 2 people were killed. Investigators recorded the probable cause as: The pilot's failure to fully advance the power levers during the takeoff and initial climb, which led to his failure to maintain sufficient airspeed and resulted in the exceedance of the airplane's critical angle of attack and a subsequent aerodynamic stall. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 8 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781190955Data APIEditorial standards

A turbofan-powered airplane stalled and crashed shortly after departure when the pilot failed to maintain sufficient airspeed, likely because the power levers were not fully advanced.

Incident

A pilot conducting a personal cross-country flight in a turbofan-powered airplane departed and shortly afterward entered a bank estimated by a witness at 90° left, with the nose parallel to the horizon. As the airplane began to roll out, the nose remained near the horizon before dropping, and the aircraft impacted the ground.

Flight Data and Conditions

Flight track data showed that after takeoff, the airplane's ground speed decreased from a maximum of 141 knots during takeoff to 100 knots at the last recorded point. About 10 minutes before the accident, the reported surface wind was from 170° at 9 knots gusting to 14 knots, resulting in a tailwind component of 1 to 2 knots. Given the airplane's configuration at impact, the indicated airspeed was estimated between 86 and 93 knots. The calculated stall speeds were 100 knots indicated airspeed (KIAS) at a 45° bank and 118 KIAS at a 60° bank. The airspeed was therefore below stall speed, and the pilot failed to maintain sufficient airspeed, leading to an aerodynamic stall.

Pilot History and Engine Examination

A pilot who had flown with the accident pilot on two prior occasions reported that the accident pilot consistently operated at reduced power settings and slower-than-normal airspeeds. During one flight a year before the accident, the witness had to manually push the power levers forward. He described the accident pilot as "very behind the airplane."

Postaccident examination of both engines found no preimpact mechanical failures. Both engines showed circumferential rub marks on rotating stages, blade tip bending opposite the direction of rotation, and debris ingestion, indicating they were producing power at impact. The right engine's full authority digital electronic control (FADEC) recorded no faults; the left engine's FADEC was damaged and could not be downloaded. According to the Airplane Flight Manual, the throttle must be advanced to the maximum takeoff detent for the FADEC to record a logic trend snapshot two seconds after takeoff. The absence of such a snapshot is consistent with the pilot not fully advancing the throttles during takeoff and initial climb.

Conclusion

The combination of flight track data, witness accounts, and engine evidence indicates that the pilot did not fully advance the power levers while maneuvering shortly after takeoff. This resulted in insufficient airspeed, exceeding the airplane's critical angle of attack, and a subsequent aerodynamic stall.

Probable cause

The pilot's failure to fully advance the power levers during the takeoff and initial climb, which led to his failure to maintain sufficient airspeed and resulted in the exceedance of the airplane's critical angle of attack and a subsequent aerodynamic stall.