NASA test fires hybrid rocket motor

akey writes "According to this CNN article, NASA engineers test fired a new hybrid rocket motor. It's not as combustible on its own as conventional solid-fuel motors, and much less expensive than liquid engines, and allegedly produces fewer noxious emissions than solid-fuel motors. An added bonus is that for the motor to burn, an oxidizing agent must be continuously injected -- unlike other solid-fuel motors, it can be turned off after ignition if necessary. It won't be ready for use on a scale for the Space Shuttle for a few years yet, but it's showing promise. "

Comments

Yawn. NASA playing catch-up.

[AJWM]

Ancient technology. A private company (American Rocket Co?) was doing this stuff ten years ago and might well have made orbit by now if the CEO (George Koopman) hadn't managed to get killed in an auto accident.

And sport rocketry hobbyists have been doing hybrids on a smaller scale for a few years now too.

NASA, particularly the rocket folks, have become as hidebound and fossilized as any other government bureaucracy. They innovate about as well as Microsoft.

Re:Yawn. NASA playing catch-up.

[AJWM]

A jab at Microsoft? Not at all, merely a comparison that most Slashdotters will understand. Writing for the intended audience, as it were.

Interesting, though, that a comparison between NASA and Microsoft is seen as a jab at Microsoft.

not a new concept

[Necron69]

Too bad the article didn't mention AMROC, the American Rocket Company, that invented hybrid solid rockets years ago. I remember hearing about these back in the late 80's.

- Necron69

Wrong on several counts

[AJWM]

Or, that turns out not to be the case.

Rubber (polybutyldiene, IIRC) is used in most large solid fuel rockets as well as the hybrids. The worst thing that can happen in a solid (or hybrid) is for the grain to crack, increasing burn surface area (thus pressure, etc, in a positive feedback loop that usually ends with spectacular bang), so rubber compounds are used to add resilience to the grain.

Further, in e.g. hybrids, the rubber is being burned in e.g. a pure O2 (injected LOX) environment, which makes for very efficient burning. Burning tires just plain do not burn well (and the rubber is mixed with all kinds of other stuff), and it's the incomplete combustion that makes tire fires so bad.

You may be right about the lower efficiency, but hybrids have advantages to counter this: lower cost to manufacture than liquid engines, and greater control than solids. (You can't stop and restart a solid, and any throttling has to be designed into the shape of the grain. Hybrids can be throttled, stopped, and restarted by controlling the oxidizer flow).

Privatize NASA?

[DHartung]

When we can get the gov't to privatize NASA, so its inherant conservatism is based on the engineering rather than beaureaucratic hoop jumping we all may just get to see our childrens children living in space.

NASA should be doing stuff like this -- studying advanced or experimental rocket technologies, the same way they study advanced flight technology. The difference is that in space, NASA is also expected to actually do the job, but for flight, the airplane industry does it.

NASA needs to get out of the spaceflight business entirely (and that is happening, sorta) and concentrate on a) research, b) planetary exploration, and c) satellite science. But this ACE delivery service stuff is well past the point where we should let private industry take over. Hopefully, some of the companies at the cusp of doing this, like Rotary Rocket or the Pioneer Pathfinder folks, will succeed in the next couple of years, and pick up where NASA left off.

This still leaves NASA with responsibility for stuff like Chandra or Cassini -- but getting "us" living in space shouldn't be a government program, just for the reasons you mention.

Re:maybe it'll shut the environuts

[SEWilco]

Ask them how much of their favorite chemical is pumped into the atmosphere annually by volcanoes.