B*V
发帖数: 3365 | 1 http://security.blogs.cnn.com/2012/08/14/imagine-flying-from-ne
Imagine flying from New York to London in under an hour
By Mike Mount, CNN Senior National Security Producer
Perhaps Han Solo said it best in Star Wars when, describing his hyper-fast
smuggling spaceship the Millennium Falcon, he said, "It may not look like
much, but it's got it where it counts."
While the Air Force might take exception to being likened to the Falcon, in
reality the platypus-nosed X-51A Waverider hypersonic flight test vehicle
really doesn't look like much. But it definitely has it where it counts.
On Tuesday, the unmanned 25-foot-long vehicle will be dropped off of the
wing of a converted B-52 bomber off the California coast and try to fly for
300 seconds at science fiction-like speeds of Mach 6, over 4,500 mph - fast
enough to fly from New York to London in less than an hour.
It is the Pentagon's latest test as it studies the possibilities of
hypersonic flight, defined as moving at speeds of Mach 5 (about 3,400 mph)
and above without leaving the atmosphere. The technology could eventually
bring missiles or airplanes to the other side of the planet in minutes
instead of hours.
The Air Force and the Pentagon are not saying much about Tuesday's test, but
the military could use such technology for reconnaissance aircraft, cruise
missile-like weapons or vehicles that could carry people or cargo so fast
adversaries would not have time to react, according to military analysts.
The Air Force conceived the X-51A program in 2004 and, according to the
military analysis website Globalsecurity.org, the service has spent $140
million on the Waverider system. The Air Force will not disclose the actual
cost of the program.
Long like a missile and with just a few fins in the rear, the Boeing-built
aircraft is not designed as a bed for a weapon, according to the Air Force,
but it is testing the technology to build future weapons around.
Past Waverider flights have come with mixed results. In May 2010, the
Waverider made its first flight at 3,500 mph for 143 seconds before a
malfunction caused the test to shut down early.
A June 2011 test also was shutdown early but did collect some data for the
Air Force.
If all goes as planned, the flight Tuesday will end with a dive into the
Pacific; there is no intent to recover the aircraft. The Air Force says the
program was designed for each vehicle to be destroyed at the end of its
flight test because of the cost that would be involved in recovering them.
Data is fed back to evaluators during the test.
The Pentagon considers hypersonic flight the new stealth. The technology
could move reconnaissance or bomber aircraft at high altitudes and speeds
that put them far out of the reach of surface-to-air missiles or other anti-
aircraft fire. The kind of speeds the X-51A is able to reach cannot be
achieved with current jet-powered technology.
The aircraft uses "scramjet" technology, an engine with virtually no moving
parts. It uses oxygen from the atmosphere for its engines, as opposed to
carrying large fuel tanks that rockets require, making it a more efficient
vehicle for military or commercial purposes.
Additionally, because of the high speeds the vehicle is also able to ride on
the shockwave it creates at six times the speed of sound, increasing
efficiency, according to an Air Force factsheet on the X-51A. It says that
is also the genesis of the vehicle's nickname, the Waverider.
The Pentagon's high-technology research group, the Defense Advanced Research
Projects Agency, or DARPA, says getting aircraft to speeds of Mach 20 -
which would enable the military to get anywhere in the world in under an
hour - is an area of research where significant scientific advancements have
eluded researchers for decades.
The Pentagon says it is studying this technology as countries have made
advances in thwarting stealth technologies the U.S military has in its
arsenal.
"That strategic advantage is threatened as other nations' abilities in
stealth and counter-stealth improve," according to DARPA website. "Restoring
that battle space advantage requires advanced speed, reach and range.
Hypersonic technologies have the potential to provide the dominance once
afforded by stealth to support a range of varied future national security
missions."
The military could use it in two realms, according to Dan Wasserbly, the
Americas editor of IHS/Jane's, a military analysis publication.
"They could use it to develop cruise missile-like weapons that could reach a
target on the other side of the planet in minutes instead of hours, as well
as developing aircraft which could put a quick-reaction force on a far-off
battleground within hours instead of days," Wasserbly said.
The Air Force has said that by 2016 it would like to have a working weapon
flying with hypersonic technology. But with the program budgeted only though
this Tuesday's test, it is unclear when anything with hypersonic technology
could be fielded, according to Wasserbly.
The Air Force made four of the X-51A test vehicles. Tuesday's test will be
the third and possibly last test, according to Air Force spokesman Daryl
Mayer.
"The Air Force will review the data from this mission and assess what will
come next," he said.
The Pentagon has also been studying other hypersonic technology, including
2010 and 2011 flight tests of the Falcon Hypersonic Test Vehicle (HTV-2)
capable of reaching Mach 20, approximately 13,000 mph, according to DARPA.
Both of those tests ended with the aircraft crashing before the tests were
complete.
So even after the Air Force evaluates the results of the Tuesday test, it
will be hard to know when the military will start launching troops from the
U.S. to a far-flung combat zone in minutes. |
|
