The new chief of the Federal Aviation Administration ordered an immediate review yesterday of computer performance at the nation's 20 air route traffic control centers after a series of recent computer failures at the Leesburg center and others.

The computers generate symbols representing airplane movements on radar screens used by air traffic controllers, who instruct pilots by radio to change their altitudes or headings to avoid other aircraft.

The Leesburg center computer, used to monitor air traffic over the 200,000 square miles between New York and South Carolina, quit working for almost 1 1/2 hours Tuesday, causing flight delays of up to 70 minutes but no hazard, FAA officials said. The center's backup computer, which also has had problems recently, was working within 35 seconds of the start of the main computer outage.

At the Boston center, which guides air traffic over the Northeast, both the main computer and backup system failed Tuesday night, leaving controllers' radar screens blank for 1 minute and 40 seconds. The main computer failed briefly several times, once for as long as 17 minutes.

Leesburg and the 19 other centers are receiving new computers with four times the capacity and 10 times the speed of the old ones.

FAA Administrator T. Allan McArtor asked for a report on the outages within 30 days.