Discussion on:

The fledgling flight of a plane which goes from London to NY in one hour

Is anyone else bothered by...

"... the prototype will be allowed to break up after deacceleration and hitting the Pacific, with no plans for recovery."
(never mind the obvious grammatical error!)

They can design a 21st century prototype aircraft engine and don't know how to incorporate one of the oldest inventions known to man - the wheel?

Sounds like government waste, if you ask me,

The problem is not that they couldn't figure out how to land but, from what I think, the reason they didn't land it and let it get destroyed is the huge amounts of forces that the plane's body would experience during both the acceleration and deceleration. Those would heavily damage the body and, of course, we have got ways of making bodies hold that much pressure (in the case of space shuttles) but, perhaps, because this is a prototype, they didn't want to spend too much on it and just want to test how the engine itself would work.

The last test flight ended in embarrassment.

This statement is designed to cover them in case another failure happens. They will say they decided to build a self destruct into it instead of crashing it.

http://www.ainonline.com/aviation-news/ain-defense-perspective/2011-07-01/scramjet-stalls-x-plane-crashes-second-flight

would it take to add navagation and landing capabilities to a largest firework ever made?

Besides the cost of the unit is not $140 million, 99% of that is in the R and D and deployment.

This is just an engine testbed. It is cheaper to build this as a disposable unit than adding time, weight & ultimately cost to make it recoverable. It either works or it doesn't, and then they build a new, modified one from scratch.

Ms. Osborne wrote:
"One day soon, it may not be an impossibility that trains traveling through vacuum tunnels...."

Sorry to tell you but the "Great Bird of the Galaxy" Gene Roddenberry used that tech in one of his "post-Star Trek" movies. He wrote a story that was made into a movie in 1973 called "Genesis II" where they had "sub-shuttles" that ran in straight lines through the Earth's crust. The only apparent difference was that, if these tunnels were vacuums, it didn't show that. They had "open air" platforms, similar to a subway platform.

As for this scramjet being allowed to disintegrate, considering that it had to be carried aloft to 50,000 feet under a B-52, it probably had no landing gear to save weight. Less weight means faster acceleration, higher altitude, and greater speed. At the lower speeds after the test, this craft may not have sufficient control surfaces to safely land the craft. The only bad thing about that is being unable to recover any of the surface materials to examine them for the effects of the high speed air on them.

The response of a variety of "skin" materials at these speeds have already been tested in real word situations. Rocket-powered missiles that fly this fast have been around for years & there's the Shuttle.
The new tech that's being tested is the scramjet engine. If it works, they'll eventually decide whether or not the same engine will be used for subsonic flight & supersonic flight. If so, it will convert from a turbojet to a ramjet while in flight at well over Mach 1. If not, an aircraft would need separate engines for different speeds.

Why are you "sorry to tell" the author that this technology has already exists? Just because it was on TV doesn't make it a real-life technology... only when it can actually be done can it be called that. So YES, this IS real, new tech.

First off, this is the second flight of the Waverider, the first one only partially successful and flying roughly 3 minutes at speed before developing problems and losing thrust.
Secondly, at hypersonic speeds, stealth is totally unnecessary as any tactical radar would detect it far too late to respond and even strategic radars would have difficulty detecting a shape meant for such speeds. External stealth technologies could create too much drag that would destroy such a ship in flight. I have no trouble with the idea of hypersonic flight, only with the idea that it even needs expensive stealth technologies.

Why make a $$$ plane when you can make a missle, or drone? Bomber launch eliminates much of the boost phase detected by sattelites. Personally, I think the only news we hear is old news. I wouldn't be surprised if this was done 10 years ago, but is just now being made public.

The travel agent told me that my cruise from New York to Iceland, Greenland, the Norwegian fiords, and Stockholm would be paired with a 1 hour flight from Stockholm back to a spot over NYC, at which time the plane would disintegrate. What part of this sounds dodgy??

You wouldn't be dead. Just pinin' for the fiords!

I would think that passengers on a flight like that would need G suits.

Not sure what G suits are, but good luck finding passengers willing and able to tolerate the acceleration/deceleration G forces in these regular NYC - London flights.

This story is another good example of magical thinking. When we still haven't figured out what to do after cheap fossil fuels, or what to do with nuke waste, what makes us think that we can conquer time and space?
How about figuring out how to move volumes of people around post-Peak oil?
And further, why is it even necessary to get from NY to London so fast?

As mentioned by others, the acceleration and deceleration speeds with the power plant design would not be practical for routine passenger use.

Scramjets had been looked at for a space plane that would take off as a normal plane and use scramjets to break out of orbit. That idea has been repeatedly proven to be too complex to be practical. The Spaceship 1 / White Knight project proved there are more cost effective alternatives.

With all that said, I am not sure why they are still doing testing of scramjets. The only other application would be weapons delivery.

Sjdelay may have hit on its purpose with the question: Plane or a Cruise Missle?

In 2010 a prototype hypersonic rocket built around a scramjet, visibly similar to the X-51, was successfully tested. It was essentially a very fast cruise missile tested as a possible replacement to conventional ballistic missiles.

It would be irresponsible to assume that any 1 technology is the only practical 1 for space launch without investigating alternatives.
A scramjet powered aircraft, whether manned or unmanned, will almost certainly use liquid fuel, although that's not limited to the hydrogen that is used in the X-51A. A scramjet powered cruise missile might use either liquid or solid fuel. Either way, a new tech cruise missile project would be more likely to be by DARPA than by NASA.

They do state that it was Jointly funded by NASA and the Pentagon.

Scramjet is an updated version of the ramjet, which is the first jet engine ever, and invented during WW2, used by Germans to propel their V-1 flying bombs from Holland to London England. The V-1 ramjet needed to be cataputed into the air to gain enough speed to provide compressed air to the combustion chamber. The scramjet uses a rocket to do the same job.

The V-1 was a pulse jet, it had shutters that closed the air intake when it fired and produced a pulse of thrust. The catapult was just because it didn't produce enough thrust to take off unassisted. Ram jets are old, though - invented in 1913.

was also a lot faster than the average passenger jet- and look where that ended up. Obviously speed isn't the number one priority amongst travelers. Safety, affordability and availability to the masses will always come first. This whole idea has already been tried in the civilian world and fell flat on its face... why would this be any different?

...when jet engines were first contemplated for use in commercial passenger aircraft. Jet engines at the time were extremely fuel-hungry and unreliable. Over time, these problems were resolved. The same may or may not be true of scram jet technology.

It's true that the Concorde was a commercial failure because R&D, construction and operating costs were never justified by the limited number of people able and willing to pay for what it would ultimately cost to travel at supersonic speed. This is likely true for hypersonic travel as well, but that doesn't mean that it's not worth experimenting with the technology.

The SR71 was designed under President Eisenhower and flew 18 months after concept was ordered. And I think it might be able to do New York to London in an hour.

Had to look it up to confirm my memory. I thought it was 2 hours.

It was 1 hour, 54 minutes, 56.4 seconds.

Remarkably that includes slowing down once to refuel from a modified KC-135 tanker.

http://www.wvi.com/~sr71webmaster/srspee~1.htm

The third X-51 test flight took place on 14 August 2012. The X-51 was to make a 300 second, or 5 minute, experimental flight at speeds of five times the speed of sound, more than 3,600 mph. After separating from its rocket booster, the craft lost control and crashed into the Pacific. A statement by the Air Force Research Laboratory indicates a failure of the tail control surface as the cause. There is now only 1 X-51 prototype remaining. http://en.wikipedia.org/wiki/Boeing_X-51