In my professional life I recently had to do some 'forensics' on a lost website. I won't bore you with the details (although it became very interesting to me). But the simple answer was although the Domain remained valid, the Hosting site was no longer being paid, so after attempting to contact their client, they closed his hosting accounts.
End of Website access:
I believe this is what has happened in this case
However this good people at the
Wayback Machine have an Archive of Lost Bombers
I have NOT investigated in detail, but whilst I suspect it is incomplete, it appears to have quite a lot of the site. For a sample of what they have Archived see:
Lost Bombers 2nd Feb 2008