THE helicopter crash which killed the owner of Leicester City Football Club Vichai Srivaddhanaprabha and four others was caused by a pin that came loose in the tail rotor control mechanism.
A report from the Air Accidents Investigation Branch revealed the pin had become disconnected, causing huge instability in the helicopter and causing the pilot to lose control of it. Mr Srivaddhanaprabha, employees Nursara Suknamai and Kaveporn Punpare, pilot Eric Swaffer and his partner, Izabela Roza Lechowicz - who was also a professional pilot - were all killed when the aircraft crashed close to the football club’s King Power Stadium on October 27. Investigators said the AW169 helicopter lost control after the pilot's pedals became disconnected from the tail rotor.
According to the AAIB report, this resulted in the aircraft making an uncotnrollable right turn before it spun and crashed into the car park.
Investigators at the crash site found parts of a mechanism had disconnected and there was a "build-up of black grease" on one component.
This caused the pitch of the tail rotor blades to change "until they reached the physical limit of their travel".
The report said: "The initiating cause and exact sequence of the failure that resulted in the loss of tail rotor control is being investigated as a priority."
"The tail rotor actuator control shaft became disconnected from the actuator lever mechanism.
"The disconnection stopped the feedback mechanism for the tail rotor actuator from operating and the tail rotor actuator from responding to yaw control inputs."