Textron Aviation Inc 172S N858AU accident near Tuskegee, Alabama

Probable cause

The flight instructor’s improper flare, which resulted in a hard landing and subsequent runway excursion.

NTSB analysis

The flight instructor was demonstrating a short-field landing to the pilot receiving instruction. The flight instructor reported that, during the landing attempt when the airplane was about 10 to 40 ft above ground level, the airplane’s airspeed decreased, and the sink rate increased. The flight instructor stated that he applied full throttle for a go-around; however, the engine did not respond and may have even further decreased before the airplane landed hard on the runway, resulting in substantial damage to the fuselage.

Review of data downloaded from the airplane’s primary flight display revealed that the airplane’s airspeed had decayed from around 50 knots to 25 knots during the landing flare and touchdown, while remaining relatively consistent at around 900 rpm. After touching down the engine power suddenly increased and reached a maximum of 1,800 rpm before then stopping completely about 7 seconds later. The data were not consistent with the flight instructor’s description that the engine power was lost or that the engine did not respond to the throttle inputs during the approach. Rather, the data suggested that the throttle application did not occur until after the airplane had contacted the runway. Following the hard landing, and subsequent runway excursion during which the nose landing gear collapsed, the engine did stop completely, and in his statement the flight instructor expressed surprise that, “…the engine was not producing any sound to indicate it was even running, nonetheless running at the appropriate rate given that the throttle was still set to maximum…” It is possible that this perception may have contributed to the instructor’s recollection of the engine not performing correctly during the accident sequence. Given this information, it is likely that the flight instructor’s improper flare resulted in a hard landing and subsequent runway excursion.

Text from the NTSB. Open the NTSB docket for ERA23LA159 for the full record.