Send an email to :
[email protected] and tell them how poor the aaib website is now it has been migrated to gov.uk. Try searching for an accident report and you will find that most have been deleted.
Contact the Cabinet Office too. The migration to .gov is their doing based on advice from their web 'guru' Martha Lane Fox of Last Minute.Com fame. Obviously she knows far more about technical websites than the punters who actually use the damn thing.