Northwest Airlines' pilots went on strike late Friday, threatening to plunge air travel into chaos across the middle of the country.
The executive council of pilots' union rejected an airline offer made about 2 1/2 hours before the strike deadline of 12:01 a.m. EDT Saturday.
About 40 Northwest planes were in the air at the time of the strike deadline. An airline spokesman said those flights would continue to their final destination, then Northwest would cease operations.
"With no agreement in place, I have instructed our strike committee to tell our pilots to withdraw all services immediately," Steve Zoller, head of the council, told reporters in Minneapolis shortly before midnight.
Northwest spokesman Jon Austin said the company would remain at the negotiating table as long as it takes, but it was unclear when, or if, talks would resume.
President Clinton said he would not intervene as he did last year when the pilots at American Airlines went on strike.
But the White House appeared to leave the door open for future intervention, if the strike is not quickly settled. Under the Railway Labor Act, which governs labor relations in the airline industry, Clinton could have ordered a 60-day cooling off period and then appointed a special emergency board to make recommendations for a settlement. The two sides would then have an additional 30 days to accept or reject the board's recommendations. If either side rejected the board's terms, the union would be once again free to strike unless Congress intervened.
Northwest, the nation's sixth largest passenger airline, controls 75 to 82 percent of the airline seats into Minneapolis, Detroit and Memphis, Tenn. It also flies into Buffalo-Niagara International Airport.
Because Northwest announced earlier in the week it was canceling 400 flights on Friday and Saturday, its hub airports in Minneapolis, Detroit and Memphis were calm.
Other airlines have said they would honor Northwest tickets, but the availability of seats was expected to be limited, with most competing airlines already heavily booked for the end of the summer season.
Trans World Airlines said it was switching to larger planes on some flights into Minneapolis, adding 85 extra seats a day. Kiwi International Air Lines said it would start two flights a day between Detroit and Newark, N.J., and Other major airlines said Friday they would wait until a strike actually happened before deciding what, if any, action to take to help stranded Northwest passengers.
Amtrak announced Friday that it would allow passengers on canceled Northwest flights to use the face value of their plane tickets toward the price of a train ticket.
Union spokesman Paul Omodt had said earlier that tentative agreements had been reached on most contract issues, but not on two of the most contentious points: job security and compensation.
Northwest pilots say they earn an average salary of about $120,000 per year. The airline says the average salary is $133,000. There are 6,100 unionized pilots at the airline.
The pilots have been seeking a 15 percent raise over five years dating to Oct. 31, 1996, when their contract expired. Airline spokesman Jon Austin said the offer on the table would give Northwest pilots pay rates 4.5 percent higher than average rate earned by pilots at American, United and Delta by the year 2000, and 7 percent higher by end of contract in 2002.
Northwest, based in Eagan, Minn., also was offering a lump sum payment to pilots of 3.5 percent of annual pay, totaling $57 million. Pilots had been seeking a stock and cash package that would be worth a total of $152.5 million.