Senators Disagree About How to Design NASA’s Heavy-Lift Rocket

If we needed any more evidence that our elected representatives should leave technical decisions to technical experts, Aviation Week provides it:

Senators who agree that NASA is taking too long to develop a design and procurement strategy for the heavy-lift Space Launch System (SLS) that Congress ordered last year cannot agree among themselves on exactly what that design should be.

At issue is what kind of power will be used in the strap-on boosters needed to get the SLS off the pad, pitting powerful senators from both sides of the aisle against members of their own political parties in a letter-writing campaign to the executive branch aimed at generating jobs for their constituents.

In January NASA selected a preliminary SLS “reference vehicle design” based on space shuttle components and the J-2X upper-stage engine. For extra power at liftoff, that design needed five-segment strap-on versions of the four-segment solid-fuel boosters built by ATK in Utah.

On June 14, NASA Administrator Charles Bolden selected and sent to the White House for confirmation his final choice for the SLS reference design. He kept the January design, but with a new wrinkle — a competition for a liquid-fueled strap-on that would make the SLS “evolvable” to meet the congressional requirement of at least 130 metric tons of lifting capability.

ACK! Why are these knuckleheads designing a rocket? Can someone explain why NASA needs a 130 MT rocket? Is it because China is considering building one? What are we going to launch on it? How are we going to be able to afford the damned thing?