Air Force's mysterious X-37B space plane passes 400 days in orbit

Re:Air Force's mysterious X-37B space plane passes 400 days ... by deletes on Tuesday February 04, 2014 @09:16AM (#7177474)

I'm not an expert but I will state that x-37 in orbit doesn't have 23km/s delta-v. I think wiki for similar vehicles can confirm that: http://en.wikipedia.org/wiki/Delta-v_budget

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Re:Air Force's mysterious X-37B space plane passes 400 days ... by VLM on Tuesday February 04, 2014 @09:27AM (#7177542)

Its a hydrazine monopropellent, or so they say, so an Isp of 250 or so would be impressive. Someone with a lot more time on their hands can tell you the mass fraction required to get 23 KM/s outta a 250 second Isp and its going to have about as many 9's as reliability marketing material. So yeah, thats not happening.

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Re:Air Force's mysterious X-37B space plane passes 400 days ... by csmithuk on Tuesday February 04, 2014 @09:22AM (#7177507)

Don't forget aerobraking which can knock a big chunk off that delta-v.

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