reply to post by Beauty_HairyBeast
could it be aurora?
there are photos and diagrams available
EXOTIC PROPULSION AIRCRAFT
While the depiction of an Aurora aircraft seems consistent with the confines of present technological imagination, other SR-71 follow-on
prognosticators suggest more alien craft. Aviation Week & Space Technology has proposed a current black aircraft that is something akin to a 1960s
Sci-Fi concept. They depict an elongated diamond shaped vehicle (one hesitates to call it an aircraft) similar to a "flattened football." The
airframe's dimensions might be 110 x 69 feet. Due to intense heat, the vehicle would have a heat-streaked appearance similar to that of the space
shuttle. Contrary to intuition, the aft body would appear distinctly more pockmarked than the fore sections, as if the most intense heat was
experienced in this region.
This vehicle would have a dual propulsion system. Jet engines buried in the fuselage would propel the vehicle to supersonic speeds, when a novel
external burning mechanism would take control as the fundamental propulsion method:
"In the high Mach regime, misted fuel is ejected from the fuselage midsection -- the 'break point' of the elongated diamond -- across the aft
surface tiles, into the area between the fuselage and a shock wave attacked to this break. In essence, the sloping, converging aft fuselage sections
form the inside of a 'nozzle' and the shock boundary constitutes the outer surface, creating an expanding exhaust effect, much like that on a
conventional rocket. The fuel is ignited by surface heating -- or other means -- creating combustion that accelerates the aircraft up to the Mach 6-8
Eliminating the human life-support requirements at Mach 8, this flaming, hypersonic pumpkin seed would be unmanned and capable of on-board self-
control. This vehicle would be as destructive as it is unusual. A payload of 120- odd nuclear weapons would be dispensed as the flaming stone skipped
across enemy skies.
The Public Record
The technical and trade press literature includes a number of references to exotic propulsion concepts that may find application in advanced military
aircraft. These include pulsed detonation engines, external combustion engines, and waveriding aerodynamics.
Pulsed detonation engines, also referred to as pulsed detonation wave engines:
"... use a shock wave created in a detonation -- an explosion that propagates supersonically -- to compress a fuel-oxidizer mixture prior to
combustion, similar to supersonic inlets that make use of external and internal shock wave for pressurization."
Although early experimental work was conducted on such propulsion concepts in the 1940s, a recent review noted:
"... there has been no previously reported use of PDE devices in any past or recent flight vehicle."
"External propulsion," like the "flaming pumpkin seed" mentioned previously, is another hypersonic propulsion technique currently being actively
explored. During the 1950s and 1960s research began on exotic external-combustion propulsion systems. An aircraft would achieve hypersonic flight by
pumping fuel from its midsection into a cone of air bounded by its shock wave. Interest in this technique continues.
"NASA said yesterday it wants to modify one of its three newly acquired SR-71A Blackbirds to prove the concept of burning hydrogen fuel outside an
engine's exhaust nozzles to improve overall flight efficiency....explore a key propulsion concept for the X-30 National Aerospace Plane known as
external burning....Engineers want to inject hydrogen fuel into the air stream under the NASP's engines and ignite it to increase pressure near the
nozzles and reduce drag....and fly at speeds up to Mach 3."
Another exotic propulsion technique is "waveriding," in which a vehicle's shock wave remains attached to the leading edge of the aircraft's body
in hypersonic flight. This makes it appear that the aircraft is riding its own shockwave. It has been reported that at least one aerospace corporation
has developed and is marketing a concept for an unmanned hypersonic vehicle that is designed to operate at speeds around Mach 10 or higher.
External Combustion Pulse Detonation Engine Aircraft
Budget and Financial Data
The previous budget analysis pertaining to Aurora is also applicable to the Exotic Propulsion Aircraft. However, while the $1.5 billion appropriated
for the Special Update Program is consistent with an effort to develop and test a single high-speed high-altitude aircraft, it is far from clear that
this amount would support more than one such effort. It may also be questioned whether decision-makers would choose to carry more than one competing
propulsion concept to the prototype flight stage of development.
Thus while budgetary considerations render plausible the existence of test prototypes of either Aurora or a more advanced Exotic Propulsion Aircraft,
the simultaneous existence of both is much less plausible. Budget and financial data do not discriminate between the relative plausibility of these
two classes of vehicles.
Copyright © William Telzerow, photographed 11/10/2006
[For some critical commentary on the significance of unusual contrail sightings, see Chris Johnson's Partial Perspective Vortex.]