Casualties unknown

2009-10-18: AT-3 R100 (SP-TPG) — Sobienie Szlacheckie, PL

Sobienie Szlacheckie, PL

On October 18, 2009, an AT-3 R100 (registration SP-TPG) was involved in an aviation accident near Sobienie Szlacheckie, PL. Investigators recorded the probable cause as: dopuszczenie do lądowania z odbiciem i utratą kierunku co przy nieadekwatnym działaniu pilota doprowadziło do znacznego odchylenia i przechylenia a następnie zderzenia z ziemią. This summary draws on records from the Polish State Commission on Aircraft Accidents Investigation (PKBWL).

Sourcesthe Polish State Commission on Aircraft Accidents Investigation (PKBWL)Primary reportUpdated 1785092869Data APIEditorial standards

On 18 October 2009, an AT-3 R100 (SP-TPG) sustained substantial damage during a landing accident at Sobienie Szlacheckie airstrip. The pilot and passenger were uninjured.

Accident Overview

On 18 October 2009 at 14:24 local time, a privately operated AT-3 R100 (registration SP-TPG) was involved in an accident during a repositioning flight from Konstancin to Sobienie Szlacheckie, Poland. The aircraft was destroyed, but the pilot and passenger escaped without injury.

Sequence of Events

The pilot, a 37-year-old male holding a CPL(A) with SEP(L) rating and approximately 268 total flight hours, was conducting the flight under VFR in daylight VMC conditions. During the approach to landing on runway 090°, with a light northerly wind of 1–2 kt, the aircraft was configured with full flaps and an initial approach speed of 100 km/h, later increased to 105 km/h. The approach trajectory was flat, prompting the pilot to momentarily increase engine power. Touchdown occurred just beyond the runway threshold with excessive sink rate, causing a bounce to an estimated height of 1–2 meters. After the bounce, the aircraft veered left about 15°. The pilot applied full right rudder and increased engine power to maintain direction and reduce sink, but the aircraft continued to yaw left to about 30°. As the pilot further increased power for a go-around, the aircraft banked left approximately 20°. The left wing struck a fence, followed by the nose and right wing impacting the ground. The aircraft then bounced and came to rest inverted, facing the landing direction.

Investigation Findings

The investigation determined that the touchdown with excessive sink rate led to a bounce and directional deviation. The pilot's subsequent control inputs were ineffective due to aerodynamic and gyroscopic effects. The increased engine power generated an asymmetric slipstream that induced a yawing moment to the left, compounded by the propeller's reaction torque and gyroscopic precession, which raised the nose and maintained a high angle of attack at low speed. The aircraft's aerodynamic control effectiveness was reduced under these conditions, a characteristic noted for ultralight low-wing aircraft with powerful Rotax engines. The pilot was likely unfamiliar with these specific handling traits.

Probable Cause

The probable cause was allowing a landing with a bounce and loss of directional control, which, combined with inadequate pilot action, led to significant deviation and bank, resulting in a collision with terrain.

Investigation report by the Polish State Commission on Aircraft Accidents Investigation (PKBWL). Original record: https://pkbwl.gov.pl/raporty/2009-0895/. This page is a structured re-presentation; facts and quotes are in the Panstwowa Komisja Badania Wypadkow Lotniczych (PKBWL), Poland.