TANGLING OVER LONDON ROUTES

The future shape of Trans World Airlines rests, in large part, on the disposition of its routes to Heathrow, London’s close-in airport. Three airlines are maneuvering for some of TWA’s U.S.-London routes. Tycoon Kirk Kerkorian said he won’t buy TWA without them.

Here is a snapshot of the events surrounding TWA’s prized London routes.

* Dec. 16: After his bid for Pan Am Corp. fails, cash-hungry TWA Chairman Carl C. Icahn switches gears and decides to shrink TWA by selling its six U.S.-London routes to American Airlines for $445 million.

* March 11: American gets British government permission to take over TWA’s routes after three months of tense negotiations. United also gets approval to buy London routes from Pan Am.

* March 14: The U.S. Department of Transportation, under pressure from Missouri legislators, tentatively allows American to buy routes to London from New York, Los Angeles and Boston. It rejects the sale of routes from Baltimore, Philadelphia and St. Louis.

* March 25: Eyeing the routes from Philadelphia and Baltimore, USAir supports DOT’s decision. Delta Air Lines objects to DOT’s ruling, saying it is better suited to fly to London from Los Angeles and Boston.

* March 29: Kerkorian and TWA’s unions team up to buy the airline, but only with the six London routes intact. American Airlines threatens to sue to protect its deal.