MHD, sub orbitals, and glowing exhaust trails

i found and interesting PDF from the DIA and NASA about various types of eletric propulsion for space and even hypersonic applications.


i found it interesting that according to the paper, these hypersonic aircraft can generate large amounts of power via it own extream exaust and plasma formation at the tip of the aircraft but dumping alki metals or mixes of them, in this case NaK also known as 'nack' it doubles as a nuclear reactor coolant(just an interesting side note).

the system is said to be able to give power in the range of kilowatts at least, and for very little cost in weight.

the paper also talks about using e-beams to create vitural inlet configurations as well as protecting the inlet via boundary layer control and the layer of plasma.

the intresting part to me is the dumping of metals into the stream or exhaust, it would like up like a neon light in the sky and leave behind it a glowing trail that would slowly fade away.

it would look orange(sodium burns orange) and some other burn green( copper compounds), the more conductive the ions the better.


but i guess if your super high up and going like a bat out of hell not much could catch you.


PAPER



some very cool looking examples of air craft/space craft in there and there are black and white picture's of some very cutting edge eletronic propulsion

a reply to: breadlover10

This is a concept paper. MHDs have been something that has been just out of reach for decades.

a reply to: Zaphod58

there is nothing in that paper that seems like its impossible and even alludes to LM working on a aircraft and engine.

other then material science(maybe) i don't see why this isnt in operation, other than money.


there have been a lot of odd sightings of aircraft with highly luminous exhaust trails of varying colors that sure sound pretty much exactly like what is in that paper.

you cant hand waive away progress.

the idea of 'virtual' inlets and bow shocks sounds a little out there and could be catastrophic if the system had a hiccup but if they have it working it could indeed change aerospace forever, and clearly they have it worked out on paper i just cant imagine this stuff not being funded in the extream.


what in your opinion makes anything in that paper impossible?

also there are pictures of working examples of the various tech working and some of them(at least 2) are on commercial sats as we speak.


with sightings matching the profile almost exactly its hard to believe there isnt at least 2 platforms using parts or all of this tech

a reply to: breadlover10

There's nothing about a TBCC that seems impossible either, but getting one to work has proven to be extremely difficult. They've been working on them for decades and have gotten them to work in small scale demonstrators, and in labs, but getting an aircraft to work with a TBCC has been a nightmare.

Nothing about the MHDs is impossible, and that isn't what I said. And I'm not hand waving away anything. But there's a huge difference between something working in a lab or wind tunnel, and flying it on a full sized aircraft. Getting it work on a satellite, designed for things like that is also a lot different from an air breathing aircraft, flying in the atmosphere. The MHD and the TBCC has been "just around the corner" for years. Like a lot of technology, scaling up is going to be difficult at best. An MHD is going to be heavy and complex, and even if they get it to work, getting other systems to play well with it is going to be its own nightmare. We're getting there, but there's going to be a lot of failure and a lot of money.

a reply to: breadlover10

Found a video from a non-government group doing MHD propulsion work.

youtu.be...

Looks like early days for them.