A YAK Service flight 9633, a Yakovlev Yak-42, crashed shortly after takeoff from Yaroslavl-Tunoshna Airport, Russia, killing 44 occupants, including one survivor. The flight was cleared for takeoff from runway 23, and the crew selected flaps at 20 degrees (takeoff position) and the stabilizer at -8.7 degrees (nose up). A control check was performed. However, the correct V1 speed should have been 210 km/h. Weather conditions were fine with wind from 360 degrees at 3 m/sec., a visibility of 10 km, with significant stratocumulus clouds at a lower limit of 990 m. The temperature was +17.8 degrees C. The takeoff was initiated at nominal engine thrust. At a speed of 185 km/h, the nose wheel lifted off the runway but the pitch angle did not increase. After six seconds takeoff mode power was selected. However, the speed momentarily decreased. The crew used additional elevator and trimmed the stabilizer to 9.5 degrees nose up. The airplane still did not become airborne. It travelled past the end of the runway onto the grass, finally lifting off about 400 metres past the threshold. The aircraft struck a localizer antenna and rapidly attained a 20 degrees nose-up attitude, reaching a height of 5-6 metres. The airplane rolled left, struck the ground, and broke up on the side of the Volga River. The incident was likely caused by an incorrect V1 speed of 190 km/h, exacerbated by the pilot’s medical issues, including leg coordination disturbances and a deep sensibility disorder. The pilot’s use of the Yak-40 aircraft’s braking method, combined with his experience in smaller Yak-40s, contributed to the problem. The crew’s failure to properly prepare for flight and coordinate their actions resulted in the incident.A YAK Service flight 9633, a Yakovlev Yak-42, crashed shortly after takeoff from Yaroslavl-Tunoshna Airport, Russia, killing 44 occupants, including one survivor. The flight was cleared for takeoff from runway 23, and the crew selected flaps at 20 degrees (takeoff position) and the stabilizer at -8.7 degrees (nose up). A control check was performed. However, the correct V1 speed should have been 210 km/h. Weather conditions were fine with wind from 360 degrees at 3 m/sec., a visibility of 10 km, with significant stratocumulus clouds at a lower limit of 990 m. The temperature was +17.8 degrees C. The takeoff was initiated at nominal engine thrust. At a speed of 185 km/h, the nose wheel lifted off the runway but the pitch angle did not increase. After six seconds takeoff mode power was selected. However, the speed momentarily decreased. The crew used additional elevator and trimmed the stabilizer to 9.5 degrees nose up. The airplane still did not become airborne. It travelled past the end of the runway onto the grass, finally lifting off about 400 metres past the threshold. The aircraft struck a localizer antenna and rapidly attained a 20 degrees nose-up attitude, reaching a height of 5-6 metres. The airplane rolled left, struck the ground, and broke up on the side of the Volga River. The incident was likely caused by an incorrect V1 speed of 190 km/h, exacerbated by the pilot’s medical issues, including leg coordination disturbances and a deep sensibility disorder. The pilot’s use of the Yak-40 aircraft’s braking method, combined with his experience in smaller Yak-40s, contributed to the problem. The crew’s failure to properly prepare for flight and coordinate their actions resulted in the incident.