WASHINGTON — U.S. Sen. Kay Bailey Hutchison (R-Texas) introduced legislation March 3 that would keep NASA flying the space shuttle program two years beyond its planned 2010 retirement and require the space agency to study options for a heavy-lift launcher that could be ready to deliver U.S. astronauts to the international space station by the end of 2013 and beyond low Earth orbit by the end of 2018.

Hutchison’s bill, if enacted, would deal a setback to U.S. President Barack Obama’s plan to retire NASA’s space shuttle fleet after four more flights and rely on Russia, and eventually U.S. firms to deliver crew and cargo to the orbiting outpost rather than continue a NASA-led effort to replace the shuttle with the Orion Crew Exploration Vehicle and it Ares 1 launcher.

“We must close the gap in U.S. human space flight or face the reality that we will be totally dependent on Russia for access to space until the next generation of space vehicle is developed,” Hutchison said in a March 3 news release. “If the space shuttle program is terminated, Russia and China will be the only nations in the world with the capability to launch humans into space. This is unacceptable.”

The bill, dubbed the Human Space Flight Capability Assurance and Enhancement Act, calls for spending an additional $3.4 billion between 2010 and 2012 to keep the space shuttle flying. The NASA budget Obama sent to Congress in February includes $989 million for the space shuttle program in 2011 and $86 million in 2012 — money meant to be used primarily for closing down the 30-year-old program.

The legislation would require NASA to spread out its four remaining shuttle missions, now slated to wrap up by October, and potentially add additional flights.

Companion legislation is expected to be introduced in the House of Representatives next week by U.S. Reps. Suzanne Kosmas (D-Fla.) and Bill Posey (R-Fla.).