I started a relatively new airline in R-Delta (hence me bringing up the problem, as it wouldn't have mattered with a larger airline.
I was just beginning to progress from a shorthaul fleet to a longhaul one, and had leased out four USED 767s. Keep in mind, this is a young airline with a limited amount of cash. Total, the sum of the initial leasing purchases came around to roughly 15 million or so.
After purchasing them and setting up a route or two with one of the aircraft, I came back about a half hour later to find that the planes were no longer operated by me and they no longer existed in my fleet, nor did the routes that they used to fly. The problem with this was that not only had I paid the initial lease costs for the aircraft, I had rented gates for a pretty high cost (relative to the wealth of the airline) and those were of no use now.
What I suspect happened was another player leased the planes out at the same time, and either they hit the lease button a moment before or after I did, so we both got charged but only one of us got the aircraft. I was under the assumption that this was a bug that had been fixed.
-EK