Below is the Denver Post article (no charge courtesy of Lt Col Jolliffe) on
the hypersonic vehicle. I queried him about how they seal the ends of the
helium tunnel and he replied they use 4 mil plastic for the tunnel and the
ends. One racer has already said he is looking into adding helium bottles
with spray nozzles in the nose to see if he couldn't realize a speed
increase from lowered drag.
What fun. I love you speed freaks!
Joliffee is now up to speed on ThrustSSC, Vesco's Turbinator and has been
invited to tour the salt with my SAE group if he so chooses. Better to have
a distant ally than close adversary, eh?
Speedy Regards,
"LandSpeed" Louise Ann Noeth
LandSpeed Productions
"Telling stories with words and pictures"
www.landspeedproductions.biz
+++++++++++++++++++++
Please find additional information (and video) at the attached web-site
http://www.46tg.af.mil/World%20Record.htm
The Denver Post article follows:
Fastest on Earth
Rocket sled hits Mach 8.6, sets land speed record
By Electa Draper, Denver Post Four Corners Bureau
HOLLOMAN AIR FORCE BASE, N.M. - At half past midnight Wednesday, a
rocket-powered sled screamed down the straightest and longest test track on
the planet at 6,453 mph - obliterating by nearly 300 mph the 1982 world land
speed record for vehicles on tracks.
>From an observation point on Tulie Peak a mile away from the track, the
hurtling sled was a bright streak of golden flame piercing the darkness
before it turned into a geyser of sparks.
"You think it's all over, and then you hear it," said Lt. Col. Russ Kurtz,
an engineer on the project. Because the speed, Mach 8.6, is almost nine
times the speed of sound, the noise of a broken sound barrier is
spine-rattling even atop Tulie Peak.
That velocity is hypersonic, beyond mere supersonic speed.
But the test run, not quite 6 seconds long, was more than a display of macho
power. The 846th Test Squadron and a client agency are developing
next-generation weapon defense. Engineers soon will be able to tell the
client, the Missile Defense Agency, exactly what happened when the 192-pound
bullet-shaped projectile riding the sled lifted off and had a short free
flight before slamming into a secret target at the end of the track. In the
process, it achieved a maximum velocity of 9,410 feet per second.
The engineers will vacuum up the pieces and analyze the damage.
"We're fighting tomorrow's war today," Kurtz said.
Kurtz likened the run to a horizontal moon shot. By itself, the record run
of the four sleds, rocket engines and a projectile assembled for the test,
which covered just more than 3 miles, cost $750,000. But it was the
culmination of five years of work, $20 million and lots of prayer, said a
smiling but clearly tired Lt. Col. James Jolliffe, head of the test group.
"I'm excited, proud and relieved," Jolliffe said just before 2 a.m.
Wednesday, after the first word on velocity made its way from the desert
floor to him.
The record set at Holloman, accomplished on tracks and with military
research backing it, is different from often cited land speed records set by
specially designed cars on wheels. The current record for those vehicles is
held by Royal Air Force pilot Andy Green, whose car reached 763 mph in 1997.
Holloman's entire test track stretches 10 miles up the Tularosa Basin, a
parched expanse between the San Andres and Sacramento mountains where even
the plants look like warriors. Yucca spears thrust out of bouquets of
quills, and creosote and mesquite hunker low over pinkish-tan earth.
At the beginning of the Cold War, the military began a search for a big
space for rocket testing. When it got a look at this basin, it pronounced it
to be its perfect "football field." And the mountains on either side were
considered great bleachers, said Dwight Harp, a community liaison to
Holloman from the nearby town of Alamogordo.
"This is a unique piece of dirt on earth," Harp said.
The basin also holds the Army's White Sands Missile Range. Not far to the
north is the Trinity Site, where the United States tested the first atomic
bomb on July 16, 1945.
The sorts of tests done at Holloman since the 1940s have helped develop
pilot ejection seats, parachutes, moon rockets, nuclear missiles and at
least one thing that everyone is supposed to use every day, seat belts.
In the 1950s, Col. John Paul Stapp, a flight surgeon, was deemed by national
media "the bravest man alive" because he rode the rocket-powered sleds at
Holloman to help the Air Force determine what could happen to pilots at
great speeds. He preferred the "bravest" label to the other one commonly
applied, "guinea pig."
Stapp's record run, also his last, took place Dec. 10, 1954, when he hurtled
at 632 mph down the track and came to a dead stop in 6.4 seconds. A
.45-caliber bullet fired at the same time and place as his departure would
have been left in his dust.
Only sophisticated mannequins ride the rails these days (there weren't even
mannequins on Wednesday's test vehicle). Now, engineers such as Kurtz, one
of 150 people behind the test, say they have the "coolest job" in the world.
His team's creation, the fastest vehicle on Earth, was really four connected
rocket-propelled sleds, which fired one after the other and then
disconnected from the train. Only the front Super Roadrunner sled bearing
the projectile or "payload" made the whole journey.
The assembly is a conglomerate of brown, black and orange steel, graphite
and other materials covered by the 150 scrawled signatures of its makers. It
is not a pretty or sleek-looking machine.
But "when you look at it through an engineer's eyes, it is a thing of
beauty," Kurtz said.
Much of Wednesday's sled trip was made through an 11,000-foot-long plastic
tunnel filled with lighter-than-air helium supplied by seven tanker trucks.
Cheap plastic is used because no matter what was put out there, it could not
withstand the forces of the sled moving through it, Kurtz said.
Explosive bolts attaching the payload to the sled blew near the end of the
track, releasing it for a short free flight before impact with the target.
Flight data were captured by a long array of spinning cameras and other
sensors.
"It sounds complicated because it is," Kurtz said. "This is rocket science."
The track is not perfectly flat. There are variances of up to
one-twelve-thousandth of an inch. The track is newly painted before each run
with graphite epoxy, which serves as a cushion and barrier that keeps
friction from welding the sled's metal slippers to the track. The thickness
of the paint differs along the length of the track and is also carefully
engineered to suit the velocities attained at various points.
"There is no such thing as a small bump when you're going 9,000 feet per
second," Kurtz said. "The sled doesn't really ride the rails. It skips down
them like a stone, hitting every 7 feet or so."
Three of four sleds are typically recoverable. And that makes such ground
tests only 1 percent as expensive as tests conducted in air and space. And
more data are captured.
Just before the historic run, Kurtz said he could not predict what might go
wrong.
"If we knew what else could go wrong, we would have engineered it out," he
said. "But we do lots of things so we don't hit birds."
That's happened. Roadrunners and coyotes have derailed tests and lost their
lives. However, the last attempt to break the land speed record, on Jan. 21,
1994, failed not because of any animal interference but because the
laminated layers of metal slippers holding sled to rail peeled apart. The
previous record, 6,122 mph, on Oct. 5, 1982, stood for more than 20 years.
But it is not about speed, Holloman officials will tell you. It is about
weaponry and power.
"We could go Mach 10," Kurtz said, "but we don't have a customer who wants
us to go there yet."
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