Former NASA Administrator Mike Griffin is unshakably opposed to switching from NASA's Ares I rocket to an upgraded Air Force Evolved Expendable Launch Vehicle, or EELV.

A chief reason: crew safety.

The Columbia Accident Investigation Board recommended that NASA retire its aging shuttle fleet as soon as possible. The design of any replacement "should give overriding priority to crew safety," the board said.

"Our probabilistic risk assessment for loss of crew on Ares I showed it to be twice as safe - I repeat, twice as safe - as a human-rated EELV-derived vehicle," Griffin said recently.

"This figure of merit was a significant factor in our decision to go with the shuttle-derived Ares I, yet is ignored by almost everyone suggesting we make a change," he said. "I cannot responsibly ignore it, for reasons having nothing to do with money."

Newsman: Stick with 'single stick'

Longtime NBC News correspondent Jay Barbree thinks NASA should stick with the "single stick" rocket rather than shift to modified military rockets.

A Merritt Island resident who has covered NASA for more than half a century, Barbree favors the Ares I rocket because it is designed to fly astronauts rather than satellites.

"The thing to do is continue on the track that they're on," he said. "The quicker they can get the space shuttle retired and get the Orion spacecraft built, the better off this country is going to be."

He also thinks it's time to venture once again beyond Earth's orbit.

"Earth is a spacecraft that's 8,000 miles in diameter, and all of us are on it. But it won't last forever," he said. "It's our cradle. But we cannot live in a cradle forever."

Keep our options open, Mars urges

Charles Mars is big on options, and he thinks the Obama administration should consider launching NASA's Orion space capsules on military rockets already flying from Cape Canaveral.

A retired NASA engineer who worked on Mercury, Gemini, Apollo, Skylab, the shuttle and Space Station Freedom, Mars wants a committee to be formed to "take a look at the Delta IV and Atlas V and see if there is an alternative" to NASA's Ares I rocket.

NASA should extend the shuttle program and see if military rockets might obviate the need to pay Russia to fly U.S. astronauts to the International Space Station, the Titusville resident said.

"We don't need to be relying on the Russians or anybody else to help our space program," Mars said. "To have to depend on them to take our astronauts and our logistics up is just not good."

Click here to view Florida Today?s Flame Trench Blog for a larger view of the paper?s Rocket Comparison Chart and link to PDF version.

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