This is reported by The Sun; I'd apply Betteridge's law [1] generously. The crash may have been caused by the rain cover, but just as well there might have been a different reason.
> Sailors saw a red cover floating in the sea after the stealth jet splashed into the Mediterranean.
It could have been anything, from a red herring to a literal red herring.
> Sailors saw a red cover floating in the sea after the stealth jet splashed into the Mediterranean.
It could have been anything, from a red herring to a literal red herring.
[1]: https://en.wikipedia.org/wiki/Betteridge's_law_of_headlines