NASA 'Hyper-X' Series Scramjets

swight1701 writes "Sciencedaily.com is reporting that NASA has revealed its plans for developing Hypersonic aircraft within 2 decades. These plans include planes that could routinely go Mach 5+ and capable of taking off from an airport and visiting the IIS, or for you earthbound folk, from one airport to any other within 2 hours. And you thought your luggage gets lost NOW.:)" NASA's release includes some graphics showing what the test vehicles look like.

Comments

Re:How do they see?

[TamMan2000]

I am going out on a limb here, but I think they have to use remote sensing because of the aerodynamics involved.

Any useful window has to have a large area projected to a plane perpendicular to the direction of travel. This would mean an extremely large window because of the wedge angle at the front of the plane. And this angle is required to be very small to keep the losses associated with the bow shock from becoming astronomical. The faster you are going (relative to the speed of sound) the smaller that angle must be to keep the shock attached and oblique.

The really interesting stuff on this craft is the engine inlets, the entire plane is designed to minimize engine inlet losses, due to shocks. Cool stuff

Re:May I ask...

[Mt._Honkey]

Read the article:

Once a hypersonic vehicle has accelerated to more than twice the speed of sound, the turbine or rockets are turned off, and the engine relies solely on oxygen in the atmosphere to burn fuel. When the vehicle has accelerated to more than 10 to 15 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain its top suborbital flight speed.

Also notice this:

NASA's Space Launch Initiative, managed by the Marshall Center, is working to develop the technology for a second-generation vehicle that could lead to a replacement for the first-generation Space Shuttle by 2012 --

I don't think that the shuttles are going to last 10 more years... they're already cracking, who knows what else might happen by then. This project should have started a long time ago. The budget is $700,000,000, which is cheap compared to the repeated launch cost of the overly expensive shuttle fleet. I'd say that it's a worthy investment.

Vapourware

[Anonymous Coward]

This whole scramjet business is a joke. A scramjet only really comes into its own at about mach 5 to mach 6. How are you going to get the craft up to that speed? There are half a dozen answers to this question, here are a few of the best options:

• use a turbojet to get to mach 2 or so, then turn on a ramjet to get to mach 5 or so and then light up your scramjet. This plane will never fly carrying two engines which are dead weight at any point in its flight.
• Launch it off of a rocket. Well, then we are back to a 2 stage to orbit vehicle which defeats the purpose of developing such a craft.
• Crazier options: Catapult launches and all sorts of other crazy stuff.

IMO NASA is wasting your tax payer dollars again.

Lets think about this for a moment...

[Mysticalfruit]

So they want to build a plane that files in atmostphere at mach 5+?

Lets think about the plane that closest fit the bill, the SR-71.

It was capable of mach 3+ and flew at an altitude of ~120,000 ft.

It was made completely out of titanium and the body of the plane got so hot that the pilot had to wear a space suit and couldn't touch the cockpit glass. The plane leaked fuel on the tarmac because it had to be designed with gaps that would close once the frame expanded from the extreme heat. In order to maintain mach 3, it had to run at full afterburners, burning a special fuel that had a super high temperature of ignition. And this was so it could carry 2 guys and a camera.

See the problems I have with this? Now granted, I'm not an airanotical engineer by any stretch of the imagination (or literate for that matter, based on my inability to spell...)

It was hard enough to get a moderately large plane going mach 3, now imagine what kind of energy you'd have to exert to get something the size of a 737 going?

Just my thoughts...