Scramjets. The cheap way into space?

[BlameTheEx]

A scramjet has been tested at Mach 9.6 here:

 

http://www.newscientist.com/news/news.jsp?id=ns99996686

 

Mach 10 is iminent

 

http://www.nasa.gov/missions/research/daily_updates.html

 

There is a little more info here:

 

http://www.nasa.gov/missions/research/f_scramjets.html

 

and a lot more here:

 

http://en.wikipedia.org/wiki/Scramjet

 

It is not possible to create a scramjet that will achieve escape velocity but scramjets are potentially cheap, and reliable, lower stage boosters for spacecraft. They burn hydrogen and air, and have no moving parts. Within a limited velocity range, and in the earths atmosphere, they have far greater thrust than an equivalent conventional rocket because they use air rather than carrying heavy oxygen tanks. NASA reckons mach 15 is a possibility. That's about 5km per second.

 

Ramjets can only operate at supersonic velocities, so at fist sight ground launching is not viable. However I could imagine a 3 stage process with something like this:

 

1) Initial boost up to supersonic speed via a low acceleration electromagnetic canon. 1km/s is possible for a 10km stretch. 20 seconds of about 5G boost. It's more plausible if you think of it as a high speed train with electromagnetic rail. This boost is not pointing upwards. It can travel along the ground. We are just getting up to scramjet operating speed.

 

2) Boost from 1km/s to 4 or 5 km/s with scramjet.

 

3) Non-reusable scramjet drops on parachute. Second stage released. Final boost from 5km/s via conventional rocket.

[Tormod]

Good post, Blame.

 

The scramjet is very interesting. I followed the X43 testing via the web and it is quite remarkable.

[alexander]

I read something about those, it seems like their problem is air friction... i know that there was a Russian research going on on reducing the drag coefficien of the front of the jet by i beleive ionizing the air 2 meters ahead of the plane therefore discharging it before it reaches the plain itself. I heard that there were reports of Russian jets flying close to a border 16 times the speed of sound. I also heard that some of the scientists moved to the US to finish what they were working on, and i think that they are doing quiet well with their experiments...

[BlameTheEx]

alexander

 

You are a moderator, and should know better. Mach 16 is far too exciting a claim to be submitted without references. I admit that detailed information is in short supply. Sadly, much of the work is being carried out under tight security. Scramjets have considerable military potential.

 

You are right about the air friction problem. A quote from the Mach 10 attempt:

 

"Reinforced carbon-carbon composite material is being added to the leading edges of the vehicle's vertical fins as well as the nose and wings to handle the higher temperatures."

[Tormod]

Here is some speculations about early Russian Mach 16 attempts:

 

http://www.astronautix.com/articles/energia.htm

 

In any event, 1986 finally saw some flight action for the new vehicles. A 1/8 scale model of Buran itself, the B-5, weighing 1,400 kg, made suborbital flights in 1986 and 1988 at Mach 16. By April of 1986, the first stage of the SL-16/strap-ons of Energia had completed four successful suborbital tests. It was also finally detected that Buran had begun flight tests, but with jet engines. By March 1987 it was verified that the SL-16 had been used for several launches.

 

IIRC the Buran was the Russian version of the Space Shuttle.

 

Here is some info about the Buran:

http://liftoff.msfc.nasa.gov/rsa/buran.html

[Tormod]

And for the record, this was with rocket engines, not scramjets.

[alexander]

You are a moderator, and should know better. Mach 16 is far too exciting a claim to be submitted without references. I admit that detailed information is in short supply. Sadly, much of the work is being carried out under tight security. Scramjets have considerable military potential.[/Quote] The fact that I'm a moderator has nothing to do with knowing better... I'm a computer person (an i moderate the computer section of the forum, surprisingly), i'm not used to the scientiffic world, thats one of the reasons i dont post much here. I share information that i know, i cant site the source not because i dont want to, but because i dont know where i heard or seen it.

I heard that there were reports of Russian jets flying close to a border 16 times the speed of sound.

Thats why i posed this not being definitive, but rather unsure....