NASA officials say they hope to launch the next space shuttle in May but admit a major technical problem might delay lift-off.

Wayne Hale, the space shuttle program manager, says NASA is preparing to launch the shuttle Discovery during a May 10-23 target window.

Hale and other NASA managers say they will not rush the flight to stay on schedule. But if Discovery does fly in May, or during the next available launching period, July 1-19, it remains possible to get three flights off this year, The New York Times reported Wednesday.

The launch schedule was disrupted by the loss of the shuttle Columbia in 2003.

Discovery's newly modified external fuel tank was to arrive Wednesday at the Space Center, allowing much less time for pre-launch testing than normal. But NASA says no part of the testing procedure will be cut short.

The testing will include wind tunnel experiments to determine whether the fuel tank can safely fly with sections of insulating foam removed. The Columbia was destroyed when foam tank debris damaged its heat shield. The craft came apart on re-entry toward a planned landing at the Kennedy Space Center. All seven astronauts aboard were killed.

Copyright 2006 by United Press International