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

12 pointsMysticFear11y ago19 comments

"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?

19 comments

gvb11y ago

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...

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

dalke11y ago

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.

Hoff11y ago

Months are not a particularly long duration for spacecraft, and solar arrays are not at all unusual as power sources for spacecraft in the inner solar system.

Some data on satellite lifetimes:

* http://www.ospo.noaa.gov/Operations/GOES/status.html

* http://noaasis.noaa.gov/NOAASIS/ml/life_expectancy.html

* http://noaasis.noaa.gov/NOAASIS/pubs/life%20expectancy.pdf (2009)

As for the protective equipment being used in that Yahoo photo, that's probably due to the use of hypergolic fuel:

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

Notice nearly-identical protective equipment being used in the Wikipedia entry.

As for protective equipment for radioisotope thermoelectric generators, here's an example from Cassini:

* http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_gen...

This being the Internet, there's far more information on related topics available:

* http://en.wikipedia.org/wiki/Corona_(satellite)

* http://en.wikipedia.org/wiki/File:U.S._RecSat_Big_Picture.jp...

Hmmm. Wonder what other and far more familiar satellite that KH-11 Kennan looks like.

* http://en.wikipedia.org/wiki/File:HST-SM4.jpeg

jeroen11y ago

Clickable url

http://news.yahoo.com/secretive-x-37b-military-space-plane-c...

JabavuAdams11y ago

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.

MysticFearOP11y ago

It states at the end: "The X-37 is powered by a single Rocketdyne AR2-3 rocket engine, manufactured by Pratt & Whitney. Each engine can produce a maximum of 29.341kN thrust and uses solar power and lithium-ion batteries instead of the traditional fuel cell system."

But earlier states: "Fuelled with military fuel JP-8 and hydrogen peroxide, the Rocketdyne engine of the X-37 is designed to run for nine months. The engine installed in the aircraft currently uses hypergolic nitrogen tetroxide or hydrazine."

Odd, no?

throwketchup11y ago

What exactly do you consider odd? As others have replied, hydrazine has a long history for RCS systems in spacecraft, and kerosene + oxidizer mixtures have long been used for propulsion engines. The only technology here that isn't entirely orthodox is the lithium battery, but that's just an evolutionary upgrade from NiCads. Apparently the range safety guys finally decided that it was ok for an unmanned craft to fly with lithium.

1 more reply

JabavuAdams11y ago

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.

stevengg11y ago

the guy who took this picture gave a talk 30c3 he takes pictures of military instantiations Seeing The Secret State: Six Landscapes

http://media.ccc.de/browse/congress/2013/30C3_-_5604_-_en_-_...

MysticFearOP11y ago

Thanks, that was really informative. The green X-Files uniform patch for the X-37 program is very ominous.

qwerta11y ago

I guess the fuel could be poisoning (that was case for some soviet military rockets). Other option is just caution not to introduce dust particles etc...

exabrial11y ago

Exact same suits being worn here...

http://en.wikipedia.org/wiki/Hydrazine#mediaviewer/File:Hype...

anovikov11y ago

It is simply an MMH or UDMH propellant onboard, which is carcinogenic.

benologist11y ago

Apparently this thing can fly 500 miles high which is space, maybe it's related to that?

http://www.space.com/25275-x37b-space-plane.html

http://en.wikipedia.org/wiki/Outer_space#Boundary

j / k navigate · click thread line to collapse

19 comments

gvb11y ago

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...