Hypersonic scramjet transports imminent.

[exoscientist]

Hot-flow test complete for Falcon ram/scramjet engine.
By Rob Coppinger
DATE:28/04/09
SOURCE:Flight International
"The US Air Force's Arnold Engineering Development Center (AEDC) has
announced completion of a hot flow test on a dual ramjet and scramjet
hypersonic engine for the Falcon combined cycle engine technology
(Facet) programme."
http://www.flightglobal.com/articles/20 ... ngine.html

Hypersonic ‘WaveRider’ poised for test flight.
U.S. military hopes to bridge the gap between airplanes and
rocketships.
By Irene Klotz
updated 12:11 p.m. ET, Wed., April 29, 2009
"Officially, it's known as the X-51, but folks like to call it the
WaveRider because it stays airborne, in part, with lift generated by
the shock waves of its own flight. The design stems from the goal of
the program — to demonstrate an air-breathing, hypersonic, combustion
ramjet engine, known as a scramjet."
...
"The holy grail of scramjet is if you can capture air while you're
flying very fast and not have to carry along an oxidizer," Brink said.
"If you could do that you've made a lot more space for payload or
cargo."
"The WaveRider's first flight is scheduled for October over the
Pacific Ocean. It will be carried into the air by a B-52 bomber, then
released at an altitude of about 50,000 feet. A solid-rocket booster
will ignite and speed it up to about Mach 4.8 and if all goes well,
the aircraft's engine will take over from there, boosting the speed to
more than Mach 6."
http://www.msnbc.msn.com/id/30477653/

Tests Are Crunch Time for Scramjet Concept.
Mar 31, 2009
"Boeing will complete assembly of the first X-51A WaveRider static
test vehicle over the next two weeks, paving the way for hypersonic
flight tests designed to show that the supersonic combustion ramjet is
ready for practical application in missiles and space launch vehicles.
"The flight tests, provisionally targeted to begin at the end of
October, mark a couple of milestones: the first attempt to fly a fuel-
cooled scramjet, and the initial try at flying an aerodynamically
unstable, control augmented hypersonic vehicle. The Pratt & Whitney
Rocketdyne SYJ61 engine at the heart of the X-51A will also be the
first liquid-hydrocarbon-fueled scramjet to fly, and is designed to
demonstrate sustained flight at up to Mach 6.5."
http://www.aviationweek.com/aw/generic/ ... el=defense

If this test of the X-51 works not only will it show that scramjets
can produce net thrust but also the waverider concept can generate a
high lift-to-drag ratio at hypersonic speeds.
This test will use a solid rocket motor to boost to Mach 4.8 before
the scramjet takes over. However it is known that ramjets can operate
to Mach 4.5+:

Lockheed Q-5/AQM-60 Kingfisher.
Data for X-7A-1, X-7A-3 and XQ-5 (AQM-60A):
Length X-7A-1: 9.98 m (32 ft 9 in)
X-7A-3: 11.3 m (37 ft)
XQ-5: 11.6 m (38 ft)
Wingspan X-7A-1: 3.7 m (12 ft)
X-7A-3, XQ-5: 3.0 m (10 ft)
Height 2.1 m (7 ft)
Diameter 61 cm (20 in)
Weight 3600 kg (8000 lb)
Speed Mach 4.3; 4500 km/h (2800 mph)
Ceiling 30000 m (100000 ft)
http://www.designation-systems.net/dusrm/m-60.html

Martin Marietta ASALM.
"In one of the PTV tests, the missile accidentally accelerated beyond
the planned speed, and eventually reached Mach 5.5 at 12200 m (40000
ft)! The planned cruise speed for operational ASALM missions was to be
around Mach 4.5 for a range of about 480 km (300 miles)."
http://www.designation-systems.net/dusr ... asalm.html

Then we could have a combined cycle ramjet/scramjet where the ramjet
is used instead of a rocket to get the vehicle to the speed where the
scramjet takes over.
The SR-71 already proved that combined cycle turbojet/ramjet
propulsion is possible. A successful X-51 test will suggest a fully
jet powered vehicle is possible to Mach 6.5 with a combined turbojet/
ramjet/scramjet engine.
Then a prototype manned Mach 6.5+ airbreathing vehicle might be
expected within a few years.
A Mach 6.5+ transport could make transatlantic and trans continental
U.S. flights in less than an hour, compared to 6 hour flights now. The
financial incentive will make it likely that a commercial transport
would be produced within a few years of the first manned prototype
vehicle.

Bob Clark

 

[exoscientist]

We might make a guess on the time frame on the development of a
hypersonic commercial transport if the X-51 test is successful based
on the case of the jet engine.

Interesting articles on the developers of the jet engine:

Frank Whittle
http://en.wikipedia.org/wiki/Frank_Whittle

Hans von Ohain.
http://en.wikipedia.org/wiki/Hans_von_Ohain

Frank Whittle in England first came up with the idea for a jet engine
in 1929. There was a lot of skepticism for the idea and he did not
come up with a working prototype then. He was able though to get a
patent on it in 1930. He was first able to come up with a working
prototype in ground tests in 1937.
Hans von Ohain in Germany independently came up with the idea in 1933.
He was also able to produce a working ground prototype in 1937. After
some more refinements, it was first tested in aircraft in 1939, only 2
years after the first successful ground tests.
After finally getting funding and support from the British government
Frank Whittle, was able to get the first tests in aircraft in 1941.
Actual deployed jet fighters for both countries came only a couple of
years after these first flying prototypes.
The first jet airliner was first tested in 1949 and came into service
in 1952:

Jet airliner.
http://en.wikipedia.org/wiki/Jet_airliner

So a prototype commercial jet transport was produced only 10 years
after a prototype jet fighter, which came only two years after the
first jet engine ground tests. Following this model, we might expect a
prototype hypersonic jet fighter within 2 years, and a prototype
hypersonic transport within 10 years after that.
The X-15 which flew up to Mach 6.7 in the 1960's was already able to
withstand the thermal heating at those speeds and likely could be an
already existing airframe to test the scramjet engine on. More
advanced airframes to optimize range and lift-to-drag ratios would be
waverider lifting body shapes:

Waverider Design.
http://www.aerospaceweb.org/design/wave ... ider.shtml

Bob Clark

 

[exoscientist]

Impetus for commercial development of a hypersonic transport might
also come from the fact that it could lead to a reusable SSTO vehicle.
Let's assume the X-51 engine will succeed to produce a Mach 6.5 ramjet/
scramjet. Very likely you could make a combined cycle turbojet/ramjet/
scramjet as the Air Force is investigating but for the purposes of
this exercise you can assume you use one of the turbojets already
capable of producing Mach 3+ thrust to get the vehicle to the speed
where the ramjet takes over.
Note this image showing the Isp's of turbojets, ramjets, scramjets
according to Mach number:

Taken from:

F-106 to X-106 Conversion Plan.
http://www.lorrey.biz/x-106/conversion.html

Assuming hydrogen fuel, use this for the Isp of the turbojet to get
the mass ratio to get to Mach 3, then the mass ratio for the ramjet to
go from Mach 3 to Mach 4.5, then finally the mass ratio for the
scramjet to go from Mach 4.5 to Mach 6.5. Finally you can use the Isp
of for example the shuttle main engines of 455 s for the mass ratio to
get to the orbital velocity of Mach 25, or 7800 m/s. Keep in mind that
since the rocket only has to take over at high altitude you can indeed
use the full vacuum Isp of the rocket engines for the rocket propelled
portion of the trip.
Note as well though there is an additional delta-v due to gravity/air
drag loss of about 1500 m/s to get to 100 km altitude for space. This
can be reduced though by the fact that you can use the ramjet/scramjet
to get to quite high altitude, say 50 km, so you would have to add on
actually a smaller delta-v, that required to get an additional 50 km
altitude using the rockets. Now also subtract from this delta-v, the
462 m/s you get for free if you launch from the equator due to the
Earth's rotation.
Multiply these mass-ratios to get the full mass ratio to orbit. I
think you'll find for a shuttle orbiter size vehicle the fuel required
would be significantly less than the shuttle's external tank and
without requiring the solid rocket boosters.

Bob Clark

 

[vulture4]

A new technolgy very much worth investigating for many civil aerospace applications. Just the sort of thing NASA should be working on, but isn't.

 

[tampaDreamer]

Clearly this is the future. Great post.

 

[exoscientist]

We might make a guess on the time frame on the development of a
hypersonic commercial transport if the X-51 test is successful based
on the case of the jet engine.

Interesting articles on the developers of the jet engine:

Frank Whittle
http://en.wikipedia.org/wiki/Frank_Whittle

Hans von Ohain.
http://en.wikipedia.org/wiki/Hans_von_Ohain

Frank Whittle in England first came up with the idea for a jet engine
in 1929. There was a lot of skepticism for the idea and he did not
come up with a working prototype then. He was able though to get a
patent on it in 1930. He was first able to come up with a working
prototype in ground tests in 1937.
Hans von Ohain in Germany independently came up with the idea in 1933.
He was also able to produce a working ground prototype in 1937. After
some more refinements, it was first tested in aircraft in 1939, only 2
years after the first successful ground tests.
After finally getting funding and support from the British government
Frank Whittle, was able to get the first tests in aircraft in 1941.
Actual deployed jet fighters for both countries came only a couple of
years after these first flying prototypes.
The first jet airliner was first tested in 1949 and came into service
in 1952:

Jet airliner.
http://en.wikipedia.org/wiki/Jet_airliner

So a prototype commercial jet transport was produced only 10 years
after a prototype jet fighter, which came only two years after the
first jet engine ground tests. Following this model, we might expect a
prototype hypersonic jet fighter within 2 years, and a prototype
hypersonic transport within 10 years after that.
The X-15 which flew up to Mach 6.7 in the 1960's was already able to
withstand the thermal heating at those speeds and likely could be an
already existing airframe to test the scramjet engine on. More
advanced airframes to optimize range and lift-to-drag ratios would be
waverider lifting body shapes:

Waverider Design.
http://www.aerospaceweb.org/design/wave ... ider.shtml

Just saw this after a web search:

Pratt & Whitney Rocketdyne Powered X-51A Hypersonic Vehicle Completes First Captive Carry Flight.
(Source: Pratt & Whitney Rocketdyne; issued December 11, 2009)
"The next B-52/X-51 flight test mission is expected in mid-January, and will be a full dress rehearsal, for its first hypersonic test flight, now planned for mid-February, Mr. Brink said. The dress rehearsal flight will depart Edwards AFB and head out over the Pacific to Point Mugu Naval Air Warfare Center Sea Range. Both airborne and multiple ground test assets will monitor all X-51A systems, but it will not be released from the B-52 and its engine will not ignite.
"In February, the Air Force Flight Test Center's B-52 will carry the unmanned X-51A to approximately 50,000 feet over the Pacific Ocean then release it. A solid rocket booster from an Army Tactical Missile System will then ignite and accelerate the X-51 to about Mach 4.5. Then the booster will be jettisoned and the X-51A's supersonic combustion ramjet propulsion system will ignite and operate for about 300 seconds, propelling the cruiser to more than six times the speed of sound."
http://www.defense-aerospace.com/articl ... hicle.html


So there will be one more unpowered test flight in January and the first flight with the scramjet fired up will be in February.


Bob Clark

 

[Astro_Robert]

This is way optimistic, and completely ignores recent military aircraft development timelines.

For the record, the D-21 drone powered by a ramjet exceeded Mach 6 way back in the 1960s. It was air-dropped of the back of an SR-71 in excess of Mach 3 and used its onboard Ramjet to accelerate as fast as it could go, estimated at over Mach 6. I am certain you could look it up under the Blackbird family.

Note that way back in the 1930s and 1940s some aircraft could be designed quick and dirty, as they were mostly hardware jobs and run by a few brilliant folks. Today is far different. Take F-22. The prototype flyoffs were in like 1991. The first EMD unit (Engineering & Manufacturing Development or Full Scale Test article) flew in ~Aug-1997. F-22 achieved IOC (Innitial Operating Capability) ~ Dec 2005. F-35 is following a similar developmental cycle. F-22 incorporated numerous improvements to existing technologies but is not as revolutionary as a hypersonic vehicle. F-22 Engines needed to suprecruise, which had been dones with the Blackbird family, it also needed stealth, supplied by Blackbird family and F-117 among others. Finally it needed very high end avionics and sensors which were in a way the most revolutionary. In many way it is the development and testing of these avionics that drives many modern development programs to be so much more lengthy than older hardware programs. We all know that Microsoft can be a pain, just think what you would go through if someone told you your life would depend on it flying your airplane or driving your car.

Think about the F-35 fighter and its F-135 engine as far as engine development goes. All that is happening is that we are taking the core engine from the F-22 and modifying it, and it is taking 10+ years from contract award. For your hypersonic vehicle you are getting a test engine in early 2010 that is suitable only for small vehicles. It will be more than 10 years before any such engine is ready to power an operational aircraft, and that is assuming an immediate crash start, something which is extremely unlikely under this administration. I would bank on 20 years prior to fielding an operation hypersonic aircraft of any kind.

 

[exoscientist]

We might make a guess on the time frame on the development of a
hypersonic commercial transport if the X-51 test is successful based
on the case of the jet engine.

Interesting articles on the developers of the jet engine:

Frank Whittle
http://en.wikipedia.org/wiki/Frank_Whittle

Hans von Ohain.
http://en.wikipedia.org/wiki/Hans_von_Ohain

Frank Whittle in England first came up with the idea for a jet engine
in 1929. There was a lot of skepticism for the idea and he did not
come up with a working prototype then. He was able though to get a
patent on it in 1930. He was first able to come up with a working
prototype in ground tests in 1937.
Hans von Ohain in Germany independently came up with the idea in 1933.
He was also able to produce a working ground prototype in 1937. After
some more refinements, it was first tested in aircraft in 1939, only 2
years after the first successful ground tests.
After finally getting funding and support from the British government
Frank Whittle, was able to get the first tests in aircraft in 1941.
Actual deployed jet fighters for both countries came only a couple of
years after these first flying prototypes.
The first jet airliner was first tested in 1949 and came into service
in 1952:

Jet airliner.
http://en.wikipedia.org/wiki/Jet_airliner

So a prototype commercial jet transport was produced only 10 years
after a prototype jet fighter, which came only two years after the
first jet engine ground tests. Following this model, we might expect a
prototype hypersonic jet fighter within 2 years, and a prototype
hypersonic transport within 10 years after that.
The X-15 which flew up to Mach 6.7 in the 1960's was already able to
withstand the thermal heating at those speeds and likely could be an
already existing airframe to test the scramjet engine on. More
advanced airframes to optimize range and lift-to-drag ratios would be
waverider lifting body shapes:

Waverider Design.
http://www.aerospaceweb.org/design/wave ... ider.shtml

A more detailed discussion of the Wednesday test flight of the X-51A
hypersonic scramjet:

Scramjet Success.
Aviation Week and Space Technology, May 28, 2010
By Graham Warwick
Washington
http://www.aviationweek.com/aw/generic/ ... %20Success

This mentions the key advance that this is over the X-43A flight that
ran on hydrogen even though that earlier flight reached higher speeds.
The X-43A flight only lasted 10 seconds before the engine melted from
the heat. The X-51A engine could run indefinitely at hypersonic
speeds, a key requirement for a engine used for transport.

I like the way Charlie Brink X-51A program manager described the
Wednesday test flight:

May 26, 2010, 6:18 p.m. EDT
Pratt & Whitney Rocketdyne Scramjet Powers Historic First Flight of
X-51A WaveRider.
"Charlie Brink, X-51A program manager with the Air Force Research
Laboratory at Wright-Patterson Air Force Base, Ohio, said: 'We are
ecstatic to have accomplished many of the test objectives on the
X-51A's very first hypersonic mission. We equate this leap in engine
technology as equivalent to the post-World War II jump from propellers
to jet engines."
http://www.marketwatch.com/story/pratt- ... _news_stmp

My opinion is that prototype scramjet flight vehicles will be fielded
in similar time frames to how soon jet aircraft prototypes were fielded
after the first working jet engines were made.

Bob Clark

 

[nimbus]

What do you think of Skylon and P2P passenger variants?

 

[exoscientist]

What do you think of Skylon and P2P passenger variants?

The main problem I think with Skylon is funding. With this successful test flight of a hypersonic airbreather I think this will open up more funding for Skylon, though the Skylon SABRE engine will operate on a different principle than the usual scramjet engine.
I think a key thing the Skylon team has to do is hypersonic wind tunnel testing of their SABRE engine. That the X-51A successfully underwent hypersonic wind tunnel testing earlier gave the X-51A team good confidence that it would actually work in flight.
Successful hypersonic wind tunnel tests of the SABRE would give people fairly good reassurance that it would actually work and therefore make people more willing to provide the funding for its development.


Bob Clark

 

[vulture4]

Scramjets and similar hypersonic airbreathing concepts could well work for military missiles, but space launch is a different situation. Airbreathing engines have a relatively narrow range of efficient operation, thus they are optimal for atmospheric cruise applications. But space launch requires continuous acceleration from zero to 7m/sec, and the most efficient trajectory (for a rocket) is to climb straight up until out of the sensible atmosphere and then turn to a near-horizontal attitude and accelerate to orbital velocity where there is no drag. With the exception of conventional subsonic carrier aircraft like the White Knight, any period of operation in air at constant speed just adds to gravity losses. Whether hypersonics will be feasible for passenger transports depends on how much of a hurry you are in; the economics did not work out for the Concorde or the proposed US SST, and unless airports get a lot more efficient, higher speeds in flight won't provide much of a reduction in travel time.

 

[annodomini2]

What do you think of Skylon and P2P passenger variants?

The main problem I think with Skylon is funding. With this successful test flight of a hypersonic airbreather I think this will open up more funding for Skylon, though the Skylon SABRE engine will operate on a different principle than the usual scramjet engine.
I think a key thing the Skylon team has to do is hypersonic wind tunnel testing of their SABRE engine. That the X-51A successfully underwent hypersonic wind tunnel testing earlier gave the X-51A team good confidence that it would actually work in flight.
Successful hypersonic wind tunnel tests of the SABRE would give people fairly good reassurance that it would actually work and therefore make people more willing to provide the funding for its development.


Bob Clark

I agree and disagree, yes more funding may speed up the Skylon program, but the funding they have is what the investors feel is necessary to prove the technology (ESA is a part of this)

Some always say why does it cost $xxBillion to design an build something, if you throw money hand over fist at something a lot will be wasted through futile efforts, more resources doesn't always result in more speed.

They are heading towards Hypersonic tests in 2011, see the Technology Demostration program on their website.

 

[annodomini2]

Scramjets and similar hypersonic airbreathing concepts could well work for military missiles, but space launch is a different situation. Airbreathing engines have a relatively narrow range of efficient operation, thus they are optimal for atmospheric cruise applications. But space launch requires continuous acceleration from zero to 7m/sec, and the most efficient trajectory (for a rocket) is to climb straight up until out of the sensible atmosphere and then turn to a near-horizontal attitude and accelerate to orbital velocity where there is no drag. With the exception of conventional subsonic carrier aircraft like the White Knight, any period of operation in air at constant speed just adds to gravity losses. Whether hypersonics will be feasible for passenger transports depends on how much of a hurry you are in; the economics did not work out for the Concorde or the proposed US SST, and unless airports get a lot more efficient, higher speeds in flight won't provide much of a reduction in travel time.

Yup this technology is really only beneficial to missiles at this time.

Hypersonic transports will be limited by the same political backlash that killed the SST and prevented the success of Concorde (No Commercial Faster than Sound travel over major land masses), which is still in effect.

The only way this could be successful, is a change in the law lifting this restriction.

For space launch, I doubt this would be beneficial, when you need 3-4 Different engines to reach orbit, you're either in Multi-stage launcher or SSTO, but carrying round lots of extra mass.

The benefit of the SABRE for SSTO is it's multi-role capability, 1 engine for the entire ride.

 

[exoscientist]

The main problem I think with Skylon is funding. With this successful test flight of a hypersonic airbreather I think this will open up more funding for Skylon, though the Skylon SABRE engine will operate on a different principle than the usual scramjet engine.
I think a key thing the Skylon team has to do is hypersonic wind tunnel testing of their SABRE engine. That the X-51A successfully underwent hypersonic wind tunnel testing earlier gave the X-51A team good confidence that it would actually work in flight.
Successful hypersonic wind tunnel tests of the SABRE would give people fairly good reassurance that it would actually work and therefore make people more willing to provide the funding for its development.

I agree and disagree, yes more funding may speed up the Skylon program, but the funding they have is what the investors feel is necessary to prove the technology (ESA is a part of this)
Some always say why does it cost $xxBillion to design an build something, if you throw money hand over fist at something a lot will be wasted through futile efforts, more resources doesn't always result in more speed.
They are heading towards Hypersonic tests in 2011, see the Technology Demostration program on their website.

On that "Technology Demonstration" page, Reaction Engines discussed testing the key components of the SABRE engine, not a hypersonic wind tunnel test of a scale operational engine:

Technology Demonstration Programme.
http://www.reactionengines.co.uk/techdemprog.html

Undoubtedly though when these separate components are proven to work, they will do hypersonic wind tunnel tests of an actual operating engine.

Bob Clark

 

[exoscientist]

Yup this technology is really only beneficial to missiles at this time.
Hypersonic transports will be limited by the same political backlash that killed the SST and prevented the success of Concorde (No Commercial Faster than Sound travel over major land masses), which is still in effect.
The only way this could be successful, is a change in the law lifting this restriction.
For space launch, I doubt this would be beneficial, when you need 3-4 Different engines to reach orbit, you're either in Multi-stage launcher or SSTO, but carrying round lots of extra mass.
The benefit of the SABRE for SSTO is it's multi-role capability, 1 engine for the entire ride.

Do a web search under the search terms "sonic boom" and "mitigation" on research to minimize the sonic boom. Several research teams have proposed solutions that are being investigated. I believe also scramjets will fly at higher altitudes which will also reduce the intensity of the boom.


Bob Clark

 

[exoscientist]

I agree and disagree, yes more funding may speed up the Skylon program, but the funding they have is what the investors feel is necessary to prove the technology (ESA is a part of this).

Found this after a web search:

VIDEO: UK nozzle could enhance SSTO propulsion.
By Rob Coppinger
on October 20, 2008 8:14 AM
http://www.flightglobal.com/blogs/hyper ... could.html

This a key piece of research because creating nozzles that would work efficiently at all altitudes is key requirement of rocket powered SSTO's as well. This is one of the few instances of where this idea is getting any king of funding.

Bob Clark

 

[annodomini2]

Yup this technology is really only beneficial to missiles at this time.
Hypersonic transports will be limited by the same political backlash that killed the SST and prevented the success of Concorde (No Commercial Faster than Sound travel over major land masses), which is still in effect.
The only way this could be successful, is a change in the law lifting this restriction.
For space launch, I doubt this would be beneficial, when you need 3-4 Different engines to reach orbit, you're either in Multi-stage launcher or SSTO, but carrying round lots of extra mass.
The benefit of the SABRE for SSTO is it's multi-role capability, 1 engine for the entire ride.

Do a web search under the search terms "sonic boom" and "mitigation" on research to minimize the sonic boom. Several research teams have proposed solutions that are being investigated. I believe also scramjets will fly at higher altitudes which will also reduce the intensity of the boom.


Bob Clark

The problem is less technical and more political, that is the law as it currently stands, getting that law undone will be a bigger challenge than building the scramjet.

 

[annodomini2]

The main problem I think with Skylon is funding. With this successful test flight of a hypersonic airbreather I think this will open up more funding for Skylon, though the Skylon SABRE engine will operate on a different principle than the usual scramjet engine.
I think a key thing the Skylon team has to do is hypersonic wind tunnel testing of their SABRE engine. That the X-51A successfully underwent hypersonic wind tunnel testing earlier gave the X-51A team good confidence that it would actually work in flight.
Successful hypersonic wind tunnel tests of the SABRE would give people fairly good reassurance that it would actually work and therefore make people more willing to provide the funding for its development.

I agree and disagree, yes more funding may speed up the Skylon program, but the funding they have is what the investors feel is necessary to prove the technology (ESA is a part of this)
Some always say why does it cost $xxBillion to design an build something, if you throw money hand over fist at something a lot will be wasted through futile efforts, more resources doesn't always result in more speed.
They are heading towards Hypersonic tests in 2011, see the Technology Demostration program on their website.

On that "Technology Demonstration" page, Reaction Engines discussed testing the key components of the SABRE engine, not a hypersonic wind tunnel test of a scale operational engine:

Technology Demonstration Programme.
http://www.reactionengines.co.uk/techdemprog.html

Undoubtedly though when these separate components are proven to work, they will do hypersonic wind tunnel tests of an actual operating engine.

Bob Clark

It uses a shock nozzle, not hypersonic airflow through the engine, they only need to understand the characteristics of the nozzle under hypersonic air flow, not the entire engine.

 

[exoscientist]

Air Force Sees Hypersonic Weapons and Spaceships in Future.
By Jeremy Hsu
SPACE.com Staff Writer
posted: 17 June 2010
05:30 am ET
"Rise of the space planes.
"If scramjet technology advances far enough, it could become part of a system that helps propel unmanned or manned vehicles into space. Space planes might even emerge that can fly into space at just about any time, without launch window constraints.
"A scramjet-powered vehicle would need to rely upon a regular rocket or jet engine to reach Mach 4, so that the scramjet could take over for hypersonic speeds during the first stage to Earth orbit.
"The X-51A scramjet engine would not be enough by itself to allow a vehicle to reach orbit, said Joseph Vogel, hypersonics director and X-51 program manager at Boeing Phantom Works/Defense, during the teleconference. Both Boeing and Pratt & Whitney Rocketdyne formed part of the private consortium that helped design and build the X-51A.
"Any future space-lift system would also need a more energetic hydrogen-based fuel, rather than the JP-7 jet fuel used in supersonic aircraft, Vogel explained.
"I would say that within the next 15 to 30 years — I'll give you the broad side — but probably 15 to 20 years, you could start to see this technology being expanded to the point where you could get aircraft into outer space," Vogel said."
http://www.space.com/businesstechnology ... 00617.html

This time estimate is for space ships. Then we would estimate the time frame for transports just within the atmosphere to be shorter.


Bob Clark