Investigators say the helicopter which crashed at Leicester City football stadium - killing the club's chairman - lost control after a mechanism became disconnected.
They say the device linking the pilot's pedals with the tail rotor blades separated before it came down in October.
Vichai Srivaddhanaprabha and four others died in the crash.
Football clubs across England continue to pay tribute to Srivaddhanaprabha, including Watford supporters, who remembered the Leicester chairman when the clubs met last weekend.
- Digital Desk