Mechanical failures after a helicopter was transported from the Falkland Islands caused it to crash land, investigators have found.
The civilian Sea King aircraft pitched nose-down after taking off from Marchwood Military Port in Hampshire in February 2018. No-one was hurt.
An Air Accident Investigation Bureau (AAIB) report found parts had corroded following a sea voyage.
Manufacturer Sikorsky has since highlighted its pre-flight procedures.
The 19-seat aircraft had been used to transport personnel and cargo on the Falklands before being shipped back to the UK for maintenance.
The AAIB report found a bearing had seized, causing it to crash nose-down within seconds of taking off on its first flight after being shipped back.
Prolonged inactivity during the transportation of the helicopter from the Falkland Islands allowed corrosion to develop sufficiently to cause the bearing to seize, the report said.
The two crew members escaped unhurt, but the helicopter had to be scrapped. After a period being unused, the helicopter should have had a safety inspection to identify such issues, the report found.
In July the manufacturer issued a safety advisory notice highlighting the need for inspections following long-term storage of the aircraft