posted on Jun, 21 2004 @ 12:33 PM
Does the United States Air Force or one of America's intelligence
agencies have a secret hypersonic aircraft capable of a Mach 6 performance?
Continually growing evidence suggests that the answer to this question
is yes. Perhaps the most well-known event which provides evidence
of such a craft's existence is the sighting of a triangular plane
over the North Sea in August 1989 by oil-exploration engineer Chris
Gibson. As well as the famous "skyquakes" heard over Los Angeles
since the early 1990s, found to be heading for the secret Groom
Lake (Area 51) installation in the Nevada desert, numerous other
facts provide an understanding of how the aircraft's technology
works. Rumored to exist but routinely denied by U.S. officials,
the name of this aircraft is Aurora.
The outside world uses the name Aurora because a censor's slip
let it appear below the SR-71 Blackbird and U-2 in the 1985 Pentagon
budget request. Even if this was the actual name of the project,
it would have by now been changed after being compromised in such
The plane's real name has been kept a secret along with its existence.
This is not unfamiliar though, the F-117a stealth fighter was kept
a secret for over ten years after its first pre-production test
flight. The project is what is technically known as a Special Access
Program (SAP). More often, such projects are referred to as "black
So what was the first sign of the existence of such an aircraft?
On 6 March 1990, one of the United States Air Force's Lockheed SR-71
Blackbird spyplanes shattered the official air speed record from
Los Angeles to Washington's Dulles Airport. There, a brief ceremony
marked the end of the SR-71's operational career. Officially, the
SR-71 was being retired to save the $200-$300 million a year it
cost to operate the fleet. Some reporters were told the plane had
been made redundant by sophisticated spy satellites.
But there was one problem, the USAF made no opposition towards
the plane's retirement, and congressional attempts to revive the
program were discouraged. Never in the history of the USAF had a
program been closed without opposition. Aurora is the missing factor
to the silent closure of the SR-71 program.
Testing such a new radical aircraft brings immense costs and inconvenience,
not just in the design and development of a prototype aircraft,
but also in providing a secret testing place for aircraft that are
obviously different from those the public are aware of.
Groom Dry Lake, in the Nevada desert, is home to one of America's
elite secret proving grounds. Here is Aurora's most likely test
location. Comparing today's Groom Lake with images of the base in
the 1970s, it is apparent that many of the larger buildings and
hangars were added during the following decade. Also, the Groom
Lake test facility has a lake-bed runway that is six miles long,
twice as long as the longest normal runways in the United States.
The reason for such a long runway is simple: the length of a runway
is determined either by the distance an aircraft requires to accelerate
to flying speed, or the distance that the aircraft needs to decelerate
after landing. That distance is proportional to the speed at which
lift-off takes place. Usually, very long runways are designed for
aircraft with very high minimum flying speeds, and, as is the case
at Edwards AFB, these are aircraft that are optimized for very high
maximum speeds. Almost 19,000 feet of the runway at Groom Lake is
paved for normal operations.
Lockheed's Skunk Works, now the Lockheed Advanced Development
Company, is the most likely prime contractor for the Aurora aircraft.
Throughout the 1980s, financial analysts concluded that Lockheed
had been engaged in several large classified projects. However,
they weren't able to identify enough of them to account for the
Technically, the Skunk Works has a unique record of managing large,
high-risk programs under an incredible unparalleled secrecy. Even
with high-risk projects the company has undertaken, Lockheed has
a record of providing what it promises to deliver.
By 1945, only a small amount of jets had the capability of reaching
speeds of 500mph. In 1960, aircraft that could exceed 1,500mph were
going into squadron service. Aircraft capable of 2,000mph were under
development and supposed to enter service by 1965. This was a four-fold
increase in speed in two decades.
From this, the next logical step was to achieve hypersonic speed.
The definition of hypersonic isn't as clearly defined as supersonic,
but aerodynamicists consider that the hypersonic realm starts when
the air in front of the vehicle's leading edges "stagnates": a band
of air is trapped, unable to flow around the vehicle, and reaches
extremely high pressures and temperatures. The edge of the hypersonic
regime lies at a speed of roughly one mile per second - 3,600mph
or Mach 5.4.
What is regarded by many as the most successful experimental aircraft
program in USAF history, the X-15 rocketplane was created in response
to a requirement issued by NASA (then NACA) for an air-launched
manned research vehicle with a maximum speed of more than Mach 6
and a maximum altitude of more than fifty miles.
The X-15 program, which involved three test aircraft, went on
to exceed all goals set and provided valuable data which has been
used on many high speed/altitude aircraft of today, including NASA
spacecraft, and most likely, the Aurora aircraft.
In the early 1960s, Lockheed and the USAF Flight Dynamics Laboratory
began a hypersonic research program which would provide data on
travel at hypersonic speed as well as more efficient shapes for
hypersonic vehicles. From this program came the FDL-5 research vehicle,
which beared an amazing resemblance to the North Sea Aurora sighting
of Chris Gibson. Building on both the FDL-5 Project and Aurora,
the aircraft which may have been seen over the North Sea could have
been Northrop's A-17 stealth attack plane.
Possible forms of hypersonic propulsion that Aurora could be using
Pulse Detonation Wave Engines
There are three reasons why the North Sea sketch drawn by Chris
Gibson is the most persuasive rendition of the Aurora vehicle. Firstly,
the observer's qualifications, with which he couldn't identify the
aircraft; which would have been instantaneous if the aircraft was
known to the "white world". Second is the fact that the North Sea
aircraft corresponds almost perfectly in shape and size to hypersonic
aircraft studies carried out by McDonnell Douglas and the USAF during
the 1970s and 1980s. The third factor is that the North Sea aircraft
looks unlike anything else. No aircraft other than a high-supersonic
vehicle, or a test aircraft for such a vehicle, has ever been built
or studied with a similiar planform.
At hypersonic speeds, traditional aerodynamic design gives way
to aero-thermodynamic design. In order for a hypersonic vehicle
to remain structurally intact at such high speeds and stresses,
the vehicle must produce minimum drag and be free of design features
that give rise to concentrations of heat. The aircraft design must
be able to spread the heat over the surface of the structure.
Thermal management is critical to high-speed aircraft, especially
hypersonic vehicles. Skin friction releases heat energy into the
aircraft and must be pumped out again if the vehicle is to have
any endurance. The only way to do this is to heat the fuel before
it enters the engine, and dump the heat through the exhaust. On
a hypersonic vehicle, thermal management is very critical, the cooling
capacity of the fuel must be used carefully and efficiently or else
the range and endurance of the aircraft will be limited by heating
rather than the actual fuel tank capacity.
So how will an aircraft reach such speeds? Conventional turbojet
engines won't be able to handle the incoming airstreams at such
speeds, they can barely handle transonic speeds. In the case of
hypersonic propulsion, an aero-thermodynamic duct, or ramjet, is
the only engine proven to work efficiently at such speeds. Even
ramjets have drawbacks though, such as drag created in the process
of slowing down and compressing a Mach 6 airstream.
To make a ramjet engine efficient is to spread the air over the
entire length of the body. In a hypersonic ramjet aircraft, the
entire underside of the forward body acts as a ramp that compresses
the air, and the entire underside of the tail is an exhaust nozzle.
So much air underneath the aircraft serves another purpose, it keeps
the plane up.
The ramjets need a large inlet area to provide the high thrust
needed for Mach 6 cruise. As a result, the engines occupy a large
area beneath vehicle and the need to accomodate a large quantity
of fuel means that an all-body shape is most feasible.
Structurally, the all-body shape is highly efficient. As well
as being extremely aerodynamic, the average cross-sectional area
being very large provides a great deal of space for load, equipment
and fuel. This being inside a structure that is light and compact
having a relatively small surface area to generate frictional drag.
The spyplane's airframe may incorporate stealth technology, but
it doesn't really require it should its mission simply involve high
altitude reconnaissance. Hypersonic aircraft are much harder to
shoot down than a ballistic missile. Although a hypersonic plane
isn't very maneuverable, its velocity is such that even a small
turn puts it miles away from a SAM's projected interception point.
Choosing The Right Fuel
Choosing the right type of fuel is crucial to the success of Aurora.
Because various sections of the craft will reach cruising-speed
temperatures ranging from 1,000 degrees fahrenheit to more than
1,400 degrees fahrenheit, its fuel must both provide energy for
the engines and act as a structural coolant extracting destructive
heat from the plane's surface.
At hypersonic speeds, even exotic kerosene such as the special
high-flashpoint JP-7 fuel used by the SR-71 Blackbird can't absorb
enough heat. The plausible solution is cryogenic fuel.
The best possibilities are methane and hydrogen. Liquid hydrogen
provides more than three times as much energy and absorbs six times
more heat per pound than any other fuel. The downfall is its low
density, which means larger fuel tanks, a larger airframe and more
drag. While liquid hydrogen is the fuel of choice for spacelaunch
vehicles that accelerate quickly out of the atmosphere, studies
have shown that liquid methane is better for an aircraft cruising
at Mach 5 to Mach 7. Methane is widely available, provides more
energy than jet fuels, and can absorb five times as much heat as
kerosene. Compared with liquid hydrogen, it is three times denser
and easier to handle.
Current Knowledge of Aurora
On 16 November 1998, a camcorder video was taken of a mysterious
"fireball" in the sky. While this was very interesting, what was
even more amazing was the aircraft which was seen shortly after
flying at very high speed producing the mysterious "donuts-on-a-rope"
contrails. Does this video, which is currently undergoing intense
study at JPL, show the mysterious Aurora spyplane?
A newspaper article about this event
was also written in the The Sun Herald newspaper.