Some good info there.
I suppose it depends on the market price for pilots over the next 30 years. Eventually, there will be one pilot, entrusted to watch the computer, but that's around 15-20 years away. So aviation is still a good industry to be employed in - although there have been better times.
Funding for the qualification is a separate issue. If the property is in a nil or negative equity situation, the banks won't lend on the property alone. But they still have you to lend on. In other words, if you go to the bank and explain what the loan is for, the bank may well feel that it's an acceptable risk (although they'll still want that second mortgage over the house, negative equity or otherwise.)