And it must compete with other big carriers doing exactly the same thing equally well.

The carrier's collapse is another significant blow to deregulation, which had sought to create several airlines able to compete with older, larger carriers.

United believes this combination will allow it to compete more profitably with short-haul carriers.

It would have to become part of a global alliance to compete with big domestic carriers.

Management says it needs the savings to compete with more efficient carriers.

Low-fare airlines, for example, are rapidly adding flights to compete with major carriers on the most lucrative routes.

Now half owned by the government, it must compete with several good-size domestic carriers and scores of upstarts for business.

It competes with such carriers in about 40 percent of its markets.

The companies said it would create an airline large enough to compete with American carriers.

"They are matching prices and in some cases have better critical mass and frequency to compete with low-cost carriers."