NASA is going to try for a new rocket jet speed record with the final unmanned X43A test flight.
The final flight of NASA's X-43A hypersonic research aircraft is still on schedule for Monday afternoon, Nov. 15, weather permitting. The mission is intended to flight-validate the operation of the X-43A's supersonic-combustion ramjet - or scramjet - engine at a record airspeed of almost Mach 10, or 10 times the speed of sound. The X-43A and its modified Pegasus booster rocket was mated to NASA's B-52B launch aircraft on Thursday, Nov. 11. Pre-flight checks of the X-43A and the booster are occurring Friday and Saturday, with final closeouts and fueling slated for Sunday, Nov. 14th. Takeoff on Nov. 15 is tentatively scheduled for about 1 p.m. Pacific time, with launch about an hour later over the Pacific test range off the coast of Southern California.
The flight will begin at Edwards Air Force Base.
As with the first two flights, the third X-43A will be carried aloft by NASA's B-52B launch aircraft from NASA's Dryden Flight Research Center on Edwards Air Force Base. The B-52B "mothership" will release the combined X-43A and Pegasus booster stack at 40,000 feet altitude off the coast of Southern California. The booster will then accelerate the experimental vehicle to nearly Mach 10, or almost 7,000 mph, at approximately 110,000 feet altitude. At booster burnout, the 2,800-pound, wedge-shaped X-43A will separate, and fly briefly on a preprogrammed path, performing a set of tasks and maneuvers before splashdown in the ocean.
In theory scramjets ought to be able to operate up to at least Mach 15.
The last X-43A vehicle has additional thermal protection for the Mach 10 flight, since it will experience heating roughly twice that of the Mach 7 vehicle. Reinforced carbon-carbon composite material has been added to the leading edges of the vehicle's vertical fins to handle the higher temperatures.
For the Mach 10 flight, which equates to approximately 7,000 mph, the booster rocket will launch the X-43A to 110,000 feet before it separates and the X-43A operates its scramjet. The research vehicle will travel about 850 miles before splashing into the ocean. As with the previous X-43A vehicles, it will not be recovered.
...
A scramjet (supersonic-combustion ramjet) is a ramjet engine in which the airflow through the whole engine remains supersonic. It is thought that a scramjet can operate from Mach 5-6 up to at least Mach 15.
The air passes through so quickly that the time available to burn fuel is extremely short.
The scramjet concept is simple: Accelerate the vehicle to about Mach 4 by a conventional jet engine, then start the scramjet engine (which has few or no moving parts) by introducing fuel and mixing it with oxygen obtained from the air and compressed for combustion. The air is naturally compressed by the forward speed of the vehicle and the shape of the inlet, similar to what turbines or pistons do in slower-moving airplanes and cars.
While the concept is simple, proving the concept has not been simple. At operational speeds, flow through the scramjet engine is supersonic - or faster than the speed of sound. At that speed, ignition and combustion take place in a matter of milliseconds. This is one reason it has taken researchers decades to demonstrate scramjet technologies, first in wind tunnels and computer simulations, and only recently in experimental flight tests.
The previous X-43A flight set a record at Mach 7.
In the process of demonstrating a scramjet-powered airplane in flight for the first time, the March 2004 flight set a world speed record for an "air breathing" (jet-powered) vehicle. It flew at nearly Mach 7, or 5,000 mph. It easily surpassed the previous record set by the military's now-retired SR-71 Blackbird high-altitude reconnaissance aircraft, which flew at about Mach 3.2.
The higher speed encountered during the 11 second burn brings hotter temperatures.
To prepare for the Mach 10 flight, the third scramjet was upgraded slightly. A thicker layer of thermal insulation was added to the engine, wing edges, tail and nose. The nose is expected to reach about 2000°C - roughly 600 degrees hotter than the previous Mach 7 flight.
Reasons not to get too excited: The aircraft is unmanned. It is a throw-away that will not be recovered when it crashes into the Pacific Ocean. NASA has no follow-on money allocated to build on this design with a better hypersonic scramjet aircraft design. The whole Hyper-X project that produced three X-43A vehicles (this is the third and final) cost $230 million. But orders of magnitude larger sums must be spent operating the obsolete Space Shuttle to go visit the white elephant International Space Station to accomplish very little real science or technological advance.
Still, useful lessons will be learned from the X-43A. Some day a new effort that pushes the envelope of scramjet operation even further may build upon what was learned in this effort.
By Randall Parker at 2004 November 12 02:50 PM Airplanes and Spacecraft | TrackBack"But orders of magnitude larger sums must be spent operating the obsolete Space Shuttle to go visit the white elephant International Space Station to accomplish very little real science or technological advance."
-and we still don't have a workable NEO mitigation and deflection program in place. And sadly, the NEO detection program isn't worth much more than the X-43A scramjet program budget-wise either.
Nasa's priorities make absolutely no sense.
Tman,
Agreed. NEO detection and deflection ought to be a high NASA priority.
Space Shuttle and ISS ought to be mothballed.
Randall,
What do you suppose the main obstacle in getting NASA to reorganize their priorities is? I have been in contact before with a Dr. Michael Pravdo from Nasa in a web chat, and he suggested that until another meteor craze sweeps the nation we will not be seeing any fundamental change in NEO priorities.
There's the possibility of a big meteor strike.
I bet an actual impact on the surface of the earth, hopefully somewhere desolate but accessable to all the photojournalists, would move NEOs right up the priority list.
The power law suggests that the next one to hit that will make people sit up and take notice is much more likely to be equal to a kilotonne or two, rather than some major TEOTWAWKI continent smasher.
But it would be better to not have to take that risk.
Tman,
I think NASA is hopeless. They like big ticket massive engineering projects like ISS, the Shuttle and the future Moon and Mars trips.
We need some near miss meteor to cruise by and scare Congress.
There was a paper a friend of mine did on the Tunguska impact from 1908 where he calculated a trajectory that would have put the strike very close to downtown Moscow had it landed about four and a half hours earlier. Estimated deaths would have been in the 10,000-100,000 range. I can only wonder what kind of world we would live in today had that thing landed earlier. I suspect a much different one than today..
Tman,
Several years ago The Economist had a front cover story on the threat of asteroids. Give some reasonable assumptions on the risk of collision of various types of asteroids and the number of deaths that would result they calculated that per dollar spent to avoid death we actually way underspend on the asteroid risk as compared to, for instance, dollars spent per life lost in aviation and in some other categories.
I read this article in hard copy. I do not know if it exists or some similar analyses exist on the web.
Thanks for the heads up Randall, I'm going to go look for it....it makes you wonder how big or how close something will have to be before we take this seriously...
Please what is the normal speed of a rocket? When rockets were first built, what was their initial/normal speeds?
I have seen some an article for a 10,000 dollar reward for innovating new wayz to space.
and I have one that involves a new type of N or ai OS that uses cellular and new type nuclear FUZE-ION ~. My colleuges call me ~ or AI or IA or N for short. I have seen pictures
of recent studies you have done and I recall A lot of what u guis photograph I have had dreams of. If you look in the world news front page thats a picture of me in one
of my out of body expiriences, the headline says Einstiens brain comes to life and reaches out to touch someone. I also have taken a digital pic of last weeks super nova from the inside out digitally w/ infared beam techno lo Gee
i like to give prove about the black hole and my bother go to america from tele lumier nursat to take photos and he go to nasa company and i like to go to nasa becouse i love evey thing that is rocket or thing that like rocket
have seen some an article for a 10,000 dollar reward for innovating new wayz to space.
and I have one that involves a new type of N or ai OS that uses cellular and new type nuclear FUZE-ION ~. My colleuges call me ~ or AI or IA or N for short. I have seen pictures
of recent studies you have done and I recall A lot of what u guis photograph I have had dreams of. If you look in the world news front page thats a picture of me in one
of my out of body expiriences, the headline says Einstiens brain comes to life and reaches out to touch someone. I also have taken a digital pic of last weeks super nova from the inside out digitally w/ infared beam techno lo Gee i like to be every think wierless to see evey thing
Tman,
Agreed. NEO detection and deflection ought to be a high NASA priority.
Space Shuttle and ISS ought to be mothballed
Several years ago The Economist had a front cover story on the threat of asteroids. Give some reasonable assumptions on the risk of collision of various types of asteroids and the number of deaths that would result they calculated that per dollar spent to avoid death we actually way underspend on the asteroid risk as compared to, for instance, dollars spent per life lost in aviation and in some other categories.
I read this article in hard copy. I do not know if it exists or some similar analyses exist on the web.