A newly modified British Airways Concorde roared across the Atlantic on Tuesday on the first supersonic test flight since the fleet was grounded last year after a crash near Paris.

With chief Concorde pilot Capt. Mike Bannister at the controls, the sleek aircraft touched down at a Royal Air Force base in Oxfordshire after the three-hour, 20-minute test flight.

The flight plan, intended to duplicate the operating conditions of Concorde's London-New York route, took the plane over the Atlantic after it took off from London's Heathrow airport at 2:18 p.m. It turned around southwest of Iceland and then headed back to Britain.

The Concorde fleets of British Airways and Air France were grounded after an Air France Concorde crashed outside Paris on July 25, 2000, killing 113 people.

Authorities believe a stray metal strip on the runway ripped one of the Concorde's tires, and rubber debris smashed into the fuel tanks, causing a leak and fire that brought the plane down.

A four-man crew checked the runway for any debris before Tuesday's test flight.

British Airways has strengthened the wiring in the undercarriages of its seven Concordes, lined the fuel tanks with Kevlar and made other changes meant to prevent fuel leaks. The French tire-maker Michelin has also developed a new extra-resistant tire to prevent punctures.

The British carrier says it hopes to fly its Concordes commercially again by late summer. Air France, which has conducted Concorde test flights at subsonic speeds, hopes to fly again by autumn.

Air France, which operates five of the planes, said Monday that it was too early to say when commercial service might resume.

"Air France and British Airways hope this resumption will be possible, but it is up to the authorities to decide," it said, referring to civil aviation authorities in France and Britain.

The British Concorde has already conducted a satisfactory taxiing trial at Heathrow. On its test flight, the supersonic aircraft was expected to reach a top speed of 1,350 mph -- around twice the speed of sound -- and climb to 60,000 feet.

The plane will remain in Oxfordshire, west of London, for checks by engineers. Further verification flights could follow.