Investigators found a £100million F-35 fighter jet crashed into the Mediterranean while taking off because the cheap rain covers had not been taken off properly. Officials believe the rain cover was sucked into the F-35B Lightning II stealth plane’s engine as it took off from the flight deck of the HMS Queen Elizabeth, forcing the pilot to eject.Naval personnel reported seeing the cover floating in the sea nearby Britain’s flagship aircraft carrier after the accident in the Mediterranean. Sources said the RAF pilot realized the issue and tried to abort take-off but was unable to stop the plane before the end of the ship’s runway. The incident triggered a frantic underwater race to find the wreckage of the stealth jet and secure the crash site a mile below the surface before other nations divers could get there first. A month later, the £100million warplane was retrieved in a secret salvage operation carried out by British, American and Italian crews, to prevent its sophisticated radar and sensors falling into the wrong hands.While the cause of the crash is still under investigation, but it is thought that a red plastic rain cover for the jet was accidentally left on and sucked into an engine.Leaked footage of the incident was also spread online, prompting an internal investigation with a sailor ending up arrested for sharing the confidential material.While it did not reveal any operationally sensitive material, the video is said to have angered naval chiefs who flew the arrested sailor back to the UK. Lockheed Martin says the F-35 ‘is the most lethal, survivable and connected fighter aircraft in the world, giving pilots an advantage against any adversary and enabling them to execute their mission and come home safe.’