NASA Tests New Breed of Propulsion Engine and System

[STS Tony]

http://www.nasa.gov/centers/marshall/news/news/releases/2006/06-010.html

[rubicondsrv]

hopefully this means that hypergols will only be used on the SM.

[Avron]

Just wondering if provinding hypergols as a backup, redundancy? I would not like to see a spacecraft with no ability to change attitude in flight.

[rubicondsrv]

that would make very little sense. the main reason fot not using hyprergolics is the increased costs for handeling the vehicle due to the toxcisity of them. add any hypergolics to the reusable portion and the reproscessing costs go up.

[AndyMc]

I missed this thread when I posted this earlier today: http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=1409&posts=1

"As 'hinted at' by Dr. Stanley in answer to my question here: http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=1258&start=141 NASA are considering Lox/Ethanol for the CEV SM propulsion and reaction control system.

http://www.nasa.gov/centers/marshall/news/news/releases/2006/06-010.html

So, the CLV looks like eventually being a 5 segment SRB, 5m diameter Lox/H2 second stage, powered by a single J2-s (J2-x) and Lox/Ethanol fuelled CSM (CEV).

Of course it could all change.......... "

I think NASA want rid of hypergols entirely, plus one less system to worry about.