Great post from Horatio.
From what I've seen, most operators have the doors closed for them when creditors wind them up. Very few would just shut up shop, as HLB said you can't just walk away. But it does amaze me how long so many people get away with trading while insolvent, or accept contracts that may take 120 days or more to get paid... and how many suppliers actually give them credit.
There are too many variables to make this a good investment. Ranging from oil prices to exchange rates, lack of security of tenure for property at the privatised airports, hostile business practices from the monopolies who ere allowed to get their hands on the infrastructure, lack of qualified senior staff (the biggest problem facing flying training at the moment) high profile people running media scare campaigns and crying wolf, new entrants who are deliberately losing money for tax reasons starting price wars, CASA and their arbitrary numbers for things like duty times forcing a business like myself to give up 10% of our trading days etc plus an election coming up which may put into power people who are hostile to private enterprise.