Accident Sequence
Shortly after receiving takeoff clearance on runway 18 at Merrill C. Meigs Field in Chicago, Illinois, the airplane impacted Lake Michigan approximately 300 feet south of the runway end. The runway measured 3,899 feet by 150 feet and was dry concrete.
The tower controller reported that at the three-quarter field point, the airplane had not rotated. The controller stated, "All I can see are lights [from the airplane]. At the point where he would have been at the end of the runway, [I] lost the lights."
A witness on the airport observed the airplane as it passed. The witness noted that the airplane "didn't sound like most King Airs do at that point." A pulsating sound was heard, though it was not heavy. According to the witness, the airplane was "bouncing up and down on the [gear] struts, and wasn't coming off the ground."
Investigation Findings
The NTSB materials examination focused on the pilot's control yoke. Small distortions were identified in the holes of the column and the rod where the control lock would be inserted. A small crack was observed around one-quarter of the control lock rod hole. The control lock was a substitute for the original airplane equipment.
Examination of the control lock revealed "several shiny scratches ... parallel to the length of the pin." A small deformation was observed near the top of the pin part of the control lock.
Additional Context
The company flight department's third pilot reported that when they flew the airplane, the control lock was always placed in the pilot's side cockpit wall pocket, along with a car key and a remote hanger door opener. During the on-scene investigation, the car key and the door opener were found in the wall pocket. The control lock itself was recovered from the lake seven days later.
Probable Cause
The official probable cause was determined to be: "On ground collision with the lake for undetermined reasons."