What happened
Following a standard taxi and run-up procedure, the pilot began the takeoff roll. During the acceleration, the aircraft failed to reach its intended rotation speed and continued down the runway. The crew member in the right seat observed the pilot attempting to pull back on the control yoke, but the mechanism remained immobile. When the second crew member attempted the same maneuver, the controls also failed to respond.
As the end of the runway approached, the copilot initiated an aborted takeoff by reducing thrust to idle and applying maximum braking. The aircraft subsequently exited the runway, traveling into rough, marshy ground where it became partially submerged in water. There were 0 fatalities reported, though the pilot sustained a head injury during the excursion.
Findings
Post-accident inspections of the aircraft revealed no mechanical failures or malfunctions in the elevator flight control rigging. Investigators located the flight control lock on the cockpit floor near the left rudder pedals. While the crew did not recall seeing the lock installed, video footage of the taxi phase showed the elevator position was consistent with the lock being engaged.
Evidence suggests the control lock remained inadvertently installed and was overlooked by both pilots. Although the pilot noted that the lock is typically stored in a flight bag, it was found unsecured on the floor. Investigators concluded that a proper flight control check prior to takeoff should have identified the restriction. Furthermore, the pilot did not abort the takeoff at the initial sign of the control anomaly, though the copilot's eventual intervention prevented more severe consequences.