The pilot receiving instruction in the multi-engine airplane reported that, during the runup, they briefed for a simulated engine failure during takeoff. He added that, during the takeoff, the flight instructor reduced the left engine throttle and the airplane veered to the left. He "lost the control" and the instructor took the flight controls. The airplane lifted off the ground into ground effect and the left wing struck the ground, exited the runway, and came to rest in the grass adjacent the runway.

The flight instructor seated in the right seat, reported that, after he reduced power on the left engine during takeoff, the pilot became confused by the sudden left yaw and did not react. He repeatedly told the pilot to abort the takeoff. Brakes were only installed on the pilot's (left) side, so the instructor was unable to apply brakes. The pilot panicked, moved the left throttle to full, remained locked on the controls, and applied back pressure on the yoke. The instructor continued to attempt to take the flight controls from the pilot, but the airplane entered ground effect. The instructor took the flight controls and, as the airplane settled to the ground, he reduced both throttles to idle. The airplane touched down in a "left yawing, slight left bank attitude" and the landing gear collapsed. The airplane skidded on the runway to the left, rotated counterclockwise, exited the runway, and came to rest in the grass.

The airplane sustained substantial damage to the left wing.

The pilot and instructor reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.