I agree with A&C; for a Director to get disqualified he has to do a major fraud and he has to do it to somebody who is big enough and ugly enough and rich enough and principled enough to want to push it through.
In my 33 years in business I have seen a few things but never saw a Director banned. The standard way to do a ripoff and get away with it is to make sure that a) you don't owe money to HMRC (who will otherwise make you personally bankrupt) and b) you don't owe more than a few k to any trade creditor.
I believe that if a flying school goes bust and you paid with a credit card, you can get your money back from the CC company. However their staff is trained to thwart any such claimback (a widespread activity) so this may take some effort.