Updated

Rep. Dave Weldon (R-Fla.) unveiled legislation Dec. 17 aimed at keeping the U.S. space shuttle fleet flying beyond its planned 2010 retirement.

The plan calls for giving NASA $3.7 billion designed to make up for past funding shortfalls that he said jeopardize continued operation of the shuttle and timely development of its planned replacement, the Orion Crew Exploration Vehicle and Ares I rocket.

The new system currently is expected to make its debut in March 2015, some four and a half years after NASA plans to fly the shuttle for the last time.

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Weldon's legislation, which he plans to introduce in Congress in coming days, would close the gap in U.S. human spaceflights by authorizing "such sums as may be necessary" to fly the space shuttle twice a year between 2010 and 2015.

"My bill plugs NASA's human spaceflight gap and ensures a smoother landing for the shuttle workforce and lift-off for Constellation," Weldon said in a statement released following a Dec. 17 press conference at the Kennedy Space Center Visitor Complex.

Weldon's office made no accommodations for media outside central Florida to cover the announcement. According to local media accounts of the event, Weldon estimated that conducting the post-2010 shuttle flights would cost $2 billion a year. NASA currently spends about twice that amount on shuttle operations.

Weldon's announcement came as Congress was poised to take up an omnibus spending bill that includes the $17.3 billion the White House requested for NASA for 2008, but would increase the agency's spending on science and aeronautics at the expense of Orion and Ares. Also stripped from the compromise measure was an extra $1 billion approved by the Senate to help NASA recover financially from the 2003 space shuttle Columbia accident.

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