I took out a loan and bought a plane.
I now have a loan AND a negative cash situation (although a positive net worth).
I was thinking about refinancing the loan, but I don't know what rate I am paying on the negative cash so I can't assess which is better.
From what I can tell, no interest is assessed for negative cash.
The downside is if you are too far negative to pay your bills/maint/etc, and you can't renew leases in negative cash scenarios. If you're only a million or two away from zero, its probably no big deal, but having the cash on hand will prevent your airline from flushing itself while you sleep at night...