spaceflight – Page 412 – Behind The Black

To save money, NASA management has shut down a troubled program to build a more efficient plutonium power supply for its deep space missions.

November 19, 2013 9:06 am Robert Zimmerman

To save money, NASA management has shut down a troubled program to build a more efficient plutonium power supply for its deep space missions.

The cancelled ASRGs would have generated electrical power from the expansion of gas warmed by the radioactive decay of plutonium-238. NASA says that the devices have the same power output as its current generation of Multi-Mission Radioactive Thermoelectric Generators (MMRTG) but use four times less plutonium-238, a scarce resource. One MMRTG with 4.8 kilograms of plutonium is currently powering the Curiosity rover on Mars.

The United States has less than 40 kilograms of plutonium-238 left, but the DOE restarted production this year. Green says he is confident that the DOE will be producing plutonium-238 at a rate of 1.5 kilograms per year by 2019. He says that the stockpiled plutonium-238, along with the new supply, will be enough to send another planned rover to Mars in 2020 and to complete other missions in the 2020s – without any need for the extra efficiency of the ASRGs.

The ASRG program had been a year and a half behind schedule and had had its management team replaced at one point.

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A close look at another government program to try to lower the cost to orbit.

November 19, 2013 8:59 am Robert Zimmerman

A close look at another government program to try to lower the cost to orbit.

The latest program is know as the Experimental Spaceplane — or XS-1. The objective “is to demonstrate a reusable first stage launch vehicle capable of carrying and deploying an upper stage that inserts 3,000 to 5,000 lb. payloads into Low Earth Orbit (LEO), designed for less than $5M per launch for an operational system.” The system has to be able to perform with aircraft-like operations. And demonstrate the ability to fly 10 times in 10 days. It needs to reach Mach 10 at least once. And provide the basis for next-generation launch services and “global reach hypersonic and space access aircraft.”

Forgive me if I am skeptical. Despite DARPA’s reasonable success (It helped make possible SpaceX’s Merlin engine), these government efforts generally fail because they are unattached to the prime reasons for lowering cost: competition and profits. Consider this very accurate historical summary in the article above:

In the era of bell bottoms and Richard Nixon, there was the space shuttle. When Ronald Reagan ruled the roost, all hope rested in the National Aerospace Plane. During the Bill Clinton era, there were the X-33 and Venture Star. In Barack Obama’s first term, the Air Force pursued its Reusable Booster System (RBS).

Five programs. One objective: to radically reduce the cost to orbit. More than $14 billion spent on development. And the result? A super expensive shuttle program. Four vehicles that never flew. And access to space just kept getting more expensive.

Only when every effort in the aerospace industry is focused on making itself more competitive will we see the kinds of technical advancements this new DARPA program wishes to achieve.