My predictions, worth considerably less than $0.02, is that sometime at the end of 2001 or first quarter or so of 2002 we will see:
1. US and HP in Ch 11, some pieces sold off to other airlines, mostly routes discontinued and the company basically liquidated after that.
2. A trip through bankruptcy chapter 11 for UA and possibly AA, but they will be reorganized and survive. They may operate for quite a while in chapter 11 as the dust settles.
3. Fewer airlines in the USA, quickie mergers bringing the number down to 3 strong airlines. My candidates as survivors: AA, DL and UA, with CO and NW absorbed between them. (Perhaps UA/CO/NW, or DL/CO/NW)
3. WN surviving as is.
I could see most USA airlines operating in chapter 11 for a while next year. It is going to be very grim. But, the survivors will be stronger, with good solid labor relations, good franchises, and a reasonable return on investment to assure that they will make plenty o' money when good times return.