There have also been occurrences where validation flights have taken place in the evening of the actual show when previous attempts have been deemed unsafe. I can recall an unfortunate F-18 pilot who never managed to pass the validation rules, he had been a late replacement after the season display pilot had been killed in an accident just before the Farnborough week. I think the Russians also struggled one year to get the cobra manoeuvre validated and he was having repeat efforts in the evening as we shuffled back to the hotel.