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X-37B plane can stay in space for years, power source?

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X-37B plane can stay in space for years, power source?

#1
"The spacecraft are able to stay in orbit for months by using a solar array to generate power."

http://news.yahoo.com/secretive-x-37b-military-space-plane-could-land-132030466.html

Why are the ground crew wearing protective gear if it just solar power? Seems like a radioactive power source with that type of protection.

Thoughts?

Re: X-37B plane can stay in space for years, power source?

#5
The protective equipment is probably for fuel or oxidizer leaks.

This page: http://www.airforce-technology.com/projects/boeing-x37/

says that the vehicle uses either hydrazine or nitrogen tetroxide.

Aside from the main engine, reaction thrusters could foul the surrounding fuselage with nasty chemicals.

Re: X-37B plane can stay in space for years, power source?

#6
It is extremely likely it is the hypergolic fuel used for the on-orbit manoeuvring rockets. Hypergolic fuel is really nasty stuff.

It is likely the same rocket fuel (maybe the same rockets) as used by the space shuttle (OMS).

http://en.wikipedia.org/wiki/Space_Shuttle_Orbital_Maneuveri...

See also:

* http://en.wikipedia.org/wiki/Space_Shuttle_Discovery#Decommi...

* http://en.wikipedia.org/wiki/Hypergolic_propellant#Disadvant...

Re: X-37B plane can stay in space for years, power source?

#7

The protective equipment is probably for fuel or oxidizer leaks. This page: http://www.airforce-technology.com/projects/boeing-x37/ says that the vehicle uses either hydrazine or nitrogen tetroxide. Aside from the main engine, reaction thrusters could foul the surrounding fuselage with nasty chemicals.

This is also why you should stay away from F-16 and other aerospace wrecks. The F-16 has a tank of hydrazine onboard. Very nasty stuff.

Re: X-37B plane can stay in space for years, power source?

#9
That's chemical protective gear designed to protect the ground crew against hydrazine or similarly hazardous vapors .

They were first developed in the 1960s for the Titan missiles, which use the chemically nasty (but room temperature) nitrogen tetroxide and Aerozine 50. See http://books.google.com/books?id=MdTZFu1fZ4AC&pg=PA186&lpg=P... for some of the history.

Here you can see the suits in use at the end of the Space Shuttle STS-1 mission: http://www.youtube.com/watch?feature=player_detailpage&v=gYc... along with explanation by both the news and NASA commentators.

http://www.xcor.com/blog/category/thrusters/ and http://www.esa.int/Our_Activities/Space_Engineering/Clean_Sp... are pictures of people in similar suits, in order to fuel spacecraft. I picked those to give commentary about how hazardous hydrazine is, and that there's a push to use alternative fuels.

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