Newswatcher:
First, the crew were not medically fit to assist in the investigation. Due to their injuries they had to have been on powerful painkillers.
Second, if there was an equipment problem that can be checked from the ground or, since it was clear, a flight check aircraft can do the approach and analyze the signal from the air.
Third, you sound like an airplane virgin. Do you fly? Have you ever dealt with the F.A.A. or your British equivalent? Never trust the Feds. They occasionally lie. At an airline I used to fly at, a Fed wrote up a bunch of our pilots by LYING about what they said to him. They got investigated. It didn't matter to this Feds' superiors that he had already had his route check authorization revoked; they started screwing with our pilots anyways. They were only cleared when one had the Fed on tape trying to coerce them to hand over maintenance records with the threat of losing their certificates. It turned out that this Fed has been repeatedly transferred around the country because of certain problems he had in dealing with people. After many thousands of dollars my friends were cleared since they had, of course, done nothing wrong. However, unlike the criminal justice system, with the FAA you are guilty until you prove yourself innocent.
How is a pilot with injuries, in shock, in pain, going to know what to say to a Fed that won't implicate him?
Always wait for the attorneys. That is what they are paid for. It is money well spent because there are some bad Feds out there and they lie.
MS