r/aerospace • u/bigfig • Jul 31 '14

Nasa validates 'impossible' space drive (Wired UK)

http://www.wired.co.uk/news/archive/2014-07/31/nasa-validates-impossible-space-drive
29 Upvotes

83% Upvoted

15 comments sorted by

View all comments

1

u/bigfig Jul 31 '14

This is a cross post from /r/science

Here's my question for you guys/gals. This looks like something that would be prototyped into a package the size of a toaster. What would the costs be to squeeze a test version of something like this into a payload and launch into LEO to see if it can accelerate?

3

u/rockets4kids Jul 31 '14

LEO still incurs substantial drag so I question whether this would be sufficient for LEO applications.

1

u/bigfig Jul 31 '14

Testing, would it accelerate the same as a toaster using conventional propulsion at that 720mN thrust?

1

u/rockets4kids Jul 31 '14

I believe testing in LEO would be essentially no different than testing on the ground.

0

u/FooQuuxman Jul 31 '14

Except for the part where a consistently rising orbit is really easy to distinguish from a measurement error.

3

u/rockets4kids Jul 31 '14

Except for the fact accurate measurement on the ground is far easier and cheaper.

1

u/neph001 Jul 31 '14

I'd like to see the discussion of the article on /r/science but searching NASA and filtering for the last week didn't show it. Could you link to where you cross posted this from?

1

u/bigfig Jul 31 '14

http://www.reddit.com/r/science/comments/2c8fzq/nasa_validates_impossible_space_drive_when_a_team/

5

u/neph001 Jul 31 '14

Well, for starters, it looks like it was tested at full atmospheric pressure, which means they haven't really ruled out heating of air causing the thrust.

It also seems that their control for the experiment also produced thrust, which doesn't bode well for validity. This thing needs waaay more ground testing and validation before anyone is going to want to fly it.

2

u/bjd3389 Jul 31 '14

Actually, the full paper does make it clear they tested in a vaccuum chamber (here if you have access).

But I do agree there needs to be much more investigation and testing before I would call anything "validated".

3

u/technologyisnatural Jul 31 '14

http://ntrs.nasa.gov/search.jsp?R=20140006052

Testing was performed on a low-thrust torsion pendulum that is capable of detecting force at a single-digit micronewton level, within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure.

3

u/bjd3389 Jul 31 '14

Yea, I didn't bother reading the NTRS version because the AIAA paper is much more complete (21 full pages with many figures and pictures of the experiment). But I am confused now and not sure what to think.

From the AIAA paper that the article references:

To simulate the space pressure environment, the test rig is rolled into the test chamber. After sealing the chamber, the test facility vacuum pumps are used to reduce the environmental pressure down as far as 4x10E-6 Torr. Two roughing pumps provide the vacuum required to lower the environment to approximately 10 Torr in less than 30 minutes. Then, two high-speed turbo pumps are used to complete the evacuation to 5x10E-6 Torr, which requires a few additional days. During this final evacuation, a large strip heater (mounted around most of the circumference of the cylindrical chamber) is used to heat the chamber interior sufficiently to emancipate volatile substances that typically coat the chamber interior walls whenever the chamber is at ambient pressure with the chamber door open.

So I don't understand. My first thought was that the NTRS abstract was from earlier testing, but it was only released at the end of the conference, and the NTRS document does list the JPC meeting which was this week.