U is a sinking ship. I have been employed here 15+ years and all but two have been traumatic. I am going into business for myself and will leave U in the next 6 months (if it is around). I would recommend to all U employees, have a back-up plan and soon!
The way I read this (from a non-accountant perspective) is that US has FUTURE obligations to pay that money, in the form of leases and new aircraft. As a result, these are not pending accounts payable but rather would be in the future. For example, $1.5bn of that is for aircraft to be delivered in 2005 and beyond. I don't see this as a major problem, as long as US generates the necessary cash in the future to pay for those obligations.
I generally trust the BBC more than any other news service for accuracy and unbiased reporting. My heart sinks on news that USAirways has understated its liabilities by more than 50% -- but I'm not particularly surprised, given the current corporate climate.
A pessimist would believe that none of our contributions are going to save the ship with those announcements. Perhaps the CWA had some inkling of this, and that's part of why they've negotiated so hard. Perhaps all the unions knew it. With the NDA's the negotiators have undoubtedly had to agree to, we have no idea what anybody knows. However, I am doggedly going to keep maintaining that in the end... everything's going to be just fine.
When U first filed for Ch.11 they reported $4 billion (approx.) in liabilities, almost indentical to their assets. It was later amended to $10.5 billion. That difference is $6.5 billion.
Maybe someone at the Beeb missed a press release and just heard "U underreports liabilities by $6.5B." So they checked the most recent numbers ($10.5B in liabilities), and are adding it onto that?
At least I hope it is something like that. I believe U originally reported $4B in liabilities (approx.), then upped it to $4-point-something-B, THEN upped it to $10.5. If it is now re-re-revised to a total of $16B-plus or so, something is indeed fishy.
I think that this money differance is what the company and the lease companys have all ready come to some sort of aggrement on keeping some of the A/C....The pilots had a t/a signed for 275 A/C out of BK...245 in BK...and GOD is saying around 280....Maybe????(which would be less job cuts).... 
The increase in the amount of debt appears to be 5.5 billion. That amount is the contractual amount owed by U to the Lessors of aircraft/engines and Aircraft Manufacturers for, what is stated as, presently leased aircraft and future deliveries. One would assume that it is the subject of ongoing negotiations, but, we all know what happens when we assume. One would expect that those committments could be reduced through the bankruptcy filing, at least to the degree that Union Employees wages could be. The main thing is that it is not new information, the 8-k filing clearly indicates that it was contained in the original paperwork.
"...During the presentation, the Company's representatives referred to the Company's $10.65 billion in balance sheet liabilities as of March 31, 2002, and commented on certain other future cash commitments that, when taken together with the Company's stated liabilities, totaled approximately $16.0 billion. These additional cash commitments include aircraft operating leases with an estimated net present value of $4 billion and estimated future aircraft purchase commitments of approximately $1.5 billion. The future cash commitments for aircraft operating leases and aircraft purchase commitments (together with related amounts to be paid in connection with the purchase of aircraft) are included in the Company's prior SEC disclosures for total future cash commitments in the Company's financial statements in accordance with accounting principles generally accepted in the United States of America (GAAP)..."