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Boeing SR-200 Dart by bagera3005 Boeing SR-200 Dart by bagera3005
Boeing SR-200 Dart


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:<1>

"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 regime."

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.<2>
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:<3>

"... 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,<4> a recent review noted:<5>

"... 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.<6> Interest in this technique continues.<7>

"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.<8>

External Combustion Pulse Detonation Engine Aircraft<9>
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.
Observer Reports

Three classes of observations have been reported to suggest the existence of an Exotic Propulsion Aircraft, possibly using a pulse detonation engine. These observations include distinctive exhaust contrails, unusual engine noises, and intercepted radio transmissions. Various reports suggest that this aircraft's "slow-frequency (about 1 Hz.) pulsing sound" was accompanied by a thick, segmented smoke trail or contrail. Lighting patterns indicated the aircraft is approximately 100 feet long.<10>

Observations of distinctive exhaust contrails that have been associated in some reports with pulsed detonation engines date back to 1989:<11>

"Described as "cotton balls strung on heavy yarn" by D.C. Card, a mechanical engineer who saw it forming at high altitude over Denver in 1989, this distinctive contrail matches exhaust patterns that could be expected from a pulse detonation engine. At its high altitude, the unknown dark-grey aircraft was barely visible in late- afternoon sunlight."

By the middle of 1992, it was reported that:<12>

"Donuts-on-a-rope contrails produced by an unknown high-speed, high-altitude aircraft have been reported throughout the U.S. and Europe, suggesting that the classified "pulser" is no longer confined to a test range... In late January, a similar contrail -- described as a "coiled spring" -- was seen over Scotland behind a very fast aircraft flying east to west. The distinctive contrails have been spotted during daylight hours over Portland, Ore.; Washington Dulles International Airport, Va.; Denver, Colo.; and Edwards AFB, Calif."

In addition, "observers" have claimed that they have heard various distinctive noises emanating from the California sky.<13>

"Observers...tell of a swift, high-altitude light that accompanies the pulsing noise....the light moved from horizon to horizon -- well over 100 miles -- in under a minute."

One observer described the noise as a:<14>

"... very, very low rumble, like air rushing through a big tube."

Another individual said it sounded as if:<15>

"... the sky itself is tearing."

While the engines are supposedly reminiscent of heavy-lift rockets, California's seasoned sky-gazers say the sound is definitely not caused by rockets.

A link between the sightings of the donut-on-a-rope contrail and the reports of distinctive sounds was established in a sighting on 23 March 1992 near Amarillo, Texas. Steven Douglas took a series of pictures of the contrail, describing the engine noise as a:<16>

"... strange, loud pulsating roar... unique... a deep pulsating rumble that vibrated the house and made the windows shake... similar to rocket engine noise, but deeper, with evenly timed pulses."

In addition to providing the first photographs of the distinctive contrail previously reported by many, the significance of this sighting was enhanced by Douglas's reports of intercepts of radio transmissions:

"Air-to-air communications... were between an AWACS aircraft with the call sign "Dragnet 51" from Tinker AFB, Okla., and two unknown aircraft using the call signs "Darkstar November" and "Darkstar Mike." Messages consisted of phonetically transmitted alphanumerics. It is not known whether this radio traffic had any association with the "pulser" that had just flown over Amarillo."

Reports from Scotland suggest that this vehicle has been tested on a world-wide basis:<17>

"People living nearby reported strange ear-splitting noises and mysterious smoke-rings in the sky early this year."


Although these observations are intriguing, they are also difficult to reconcile with one another. While many observers agree on the unusual sounds created by these vehicles, a range of descriptions are provided as to the nature of these sounds. The pulsating tone emanating from these sightings has been taken as an indication of the use of some form of pulse detonation engine. Some observers report a characteristic frequency as high as 60 Hertz, while others suggest a frequency as low as 1 Hertz.

But a technical analysis of pulse detonation engines suggests that engines operating at the thrust levels associated with military aircraft would operate a between 100 and 200 Hertz (pulses per second).<18> While doppler shifting may reconcile this value with the reported 50-60 Hertz pulsation, it is more difficult to reconcile this with the reports of a 1 Hertz pulsation.

It is also difficult to reconcile a pulse rate of 100-200 Hertz with the observed donut-on-a-rope contrails.<19> The association of these contrails with a pulse detonation engine would seem to be predicated on the observation that each "donut" is a product of a single pulse detonation. Based on published photographs, the "donuts" appear to be approximately 100 meters apart. Assuming a detonation pulse rate of 100 Hertz, this would imply a velocity of 10 kilometers per second, or 36,000 kilometers per hour (roughly Mach 36), one- and-one-half times orbital velocity. While it is asserted that the Exotic Propulsion Aircraft is a high-speed vehicle, this is at least four times faster than the speeds normally associated with this aircraft.

In addition, a closer examination of the published photographs reveals a significant irregularity in the spacing between the donuts on the rope. This would seem to be inconsistent with the normal functioning of a pulse detonation engine.

While various assumptions might be brought forward to reconcile these observations with theory, the evidence is not obviously consistent with the presence of a pulse detonation engine.

And the unusually loud, rumbling sonic booms reported along the California coast actually have a precedent in a deep black program well prior to the 1970s era THAP. According to an historical Lockheed document, during test flights at high altitude, the Lockheed A-12 "Oxcart" (an SR-71 predecessor) would make an "ominous rumble on the ground.<20> Thus, while the reports of unusual auditory signatures may be indicative of the existence of some type of advanced air vehicle, they do not appear to constitute conclusive evidence of the existence of an Exotic Propulsion Aircraft.
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vharshyde Featured By Owner Jul 15, 2013
Interesting concept design, but the airframe doesn't seem to fit the specifications. The size alone coupled with the harsh point of the leading edges on each corners would cause a midair breakup at speeds much higher than about Mach 3 or 4, the forward edge, sloped or not, simply giving too much surface area in the wrong shape. Additionally, you're talking about a very large craft, propelled by four very large turboprops, with either A: minimal fuelspace(And thus almost no combat range), or B: at the rate of fuselage heating you're talking about, a massive fuel air explosive waiting to happen with little notice. Fuel burning on the trailing edge of the wing is one thing. It burning on the outside is another entirely.

Let's talk flaps for a moment. A plane like this would need Constant corrections from all angles due to its shape and lack of proper control rudders, which would require a pretty sophisticated computer system, to start with. Additionally, if you're burning fuel on the tailing edge of the wing expecting to ride the fuel's blast wave(Which, at that speed, might be moving slower than you are, which wouldn't accelerate you very much), can you guarantee that these flaps, with their microcorrections constantly being necessary, would manage to stay aligned properly? I can almost guarantee that they would not.

Regarding payload, if you want to deliver a hefty payload, you're going to have to sacrifice a lot of space for fuel. Because this shape of craft would not tolerate external hardpoints, you're very limited on your space internally. Sacrificing a pilot only goes so far, as the machinery required to arm, turn, drop, and fire a warhead takes up far more room than a pilot would to begin with. Even with the oversized airframe(Which those engines would struggle to get off of a runway, even at full burn), you're talking about a Lot more weight, Per warhead, as well as concerns regarding defending the craft from being shot down. So sorry, but no, that's not, as they say, going to fly.

It's a fun picture, but the specifications remind me very much of a child's drawing of a submarine/boat/plane/spaceship hybrid with lasers and giant rockets and robots coming out of it. Interesting on paper, but wholly unrealistic.
bagera3005 Featured By Owner Jul 15, 2013  Professional Interface Designer
7 years no work of your own i hate  design  criticism from some one thats never lifted a pin to paper
vharshyde Featured By Owner Sep 4, 2013
It's called aerodynamics. You can pretend you're above criticism all you want, but the real world, and the science behind it, will shoot you down every time.
EagleDrummer17 Featured By Owner Jun 24, 2013
I saw a documentary with limited information of the development of the SR-71, and one of the test pilots said that "Oxcart" was the codename for the Blackbird when it was being developed.
truemouse Featured By Owner Jan 21, 2010
Nothing says "You're gonna die!" more than seeing a stealth pebble gunning for you.
Kryptid Featured By Owner Jan 21, 2010
I've heard of the "flaming pumpkinseeds" before. They're a very interesting concept. Very sleek. I hope sideslip wouldn't be a problem.
Ovni-the-UFO Featured By Owner Jan 21, 2010
I thought the 'Darkstar' aircraft were generally considered to be Aurora, as were the strange contrails and sonic booms over California. o.o
JonathanBluestone Featured By Owner Jan 21, 2010  Hobbyist General Artist
As a professional UFOlogist of more than twenty years experience I have travelled the world quite extensively, and was witness to something like this while in the San Luis Valley region of Colorado about six or seven years ago. Although the craft I observed left a pulse-cloud in its wake and seemed to have an adverse affect on cloud formations suggesting Orgone technology, but that is merely speculation as I have no firm evidence to support such theories.
Ovni-the-UFO Featured By Owner Jan 22, 2010

I know that contrails can do some strange things, especially if there's temperature inversions crossing part of the contrail.

As far as pulsing clouds coming off the craft, that's common with supersonic jets in general. Faster you're going, more often the water-vapor cone appears. It gives no clue as to engine type, as far as I know, only speed.

UFOlogist? Does that mean you study unidentified flying objects in general (including terrestrial craft, such as military or private venture), or just look for alien craft?
JonathanBluestone Featured By Owner Jan 24, 2010  Hobbyist General Artist
Yes, UFOlogist, and the study does involve the mundane as well as the unexplained. It is prudent to attempt to identify an object or phenomenon as a known object or meteorological manifestation before attempting to say its a UFO. Sadly, there are too many things seen in the skies that have a plausable explaination, and a hell of a lot of other things that cannot be explained - purely because of the way they act, manoeuver and travel both in motion and in speed, accleration and behavour. In my work, a lot of which is historical in nature, it also becomes necessary to take into account technologies of the era that the phenomenon are observed in and allow for those possibilities. In the instance of the 1894-97 airship sightings seen over North America, and the later sightings made of airships in 1908-09, many of the objects observed did not act in regards to the known technologies of that era. The same is true of many other instances of Ghost Aeroplanes, Ghost Rockets and other pre-atomic sightings, including the Foo Fighters observed during the late Thirties and Forties over Europe and the Pacific.
Ovni-the-UFO Featured By Owner Jan 24, 2010
Well, UFO, by definition, means ANY object for which you have no explaination. If you go "That's a alien spacecraft", "That's a bird", "That's a plane", "That's Superman", "that's a meteorological/geologic formation", it automatically becomes an IFO (even if the identification is wrong). o: That's how I was always explained it by some guys at the local airforce/army base.

I have a theory for alot of the late nineteen-fourties UFO sightings: Nazi aircraft being tested by the USAAC (later USAF) as part of the larger Project Paperclip of integrating Nazi scientists and inventions into american society...say, the Mount Rainer sighting where the term 'flew like a saucer skipping over water' was used....the craft remind me very strongly of the Nazi flying wings. :3
ONI-Defense Featured By Owner Jul 9, 2013  Hobbyist Digital Artist
I always thought those looked like Ho-X's and other Horten designs.
JonathanBluestone Featured By Owner Jan 25, 2010  Hobbyist General Artist
Well, on June 24th 1947 Kenneth Arnold saw a line of objects, flying in an inverted V formation if we are to believe his story (The Coming of the Saucers, privately published). The question is, IF the objects seen were HPAC or even man-made why did the Air Force deem it necessary to fly them over Portland, Oregon around that same time, in full view of the public? And yes, I quite agree with your comments about IFOs but unlike some, I choose not to immediately rush at any unidentified object and claim that it HAS to be non-terrestrial because it remains unidentified. Concerning the Nazi machines, the V-7 and so on, there is no evidence to suggest the USAAF (United States Army Air Force) or any other agency including the Soviets had access to them, or even if they even existed outside of rumor because I and other researchers in this field have yet to see popular media coverage of them in detail, or even see one of them in any condition (with or without a machine gun on its ventral surface) in a museum or in photographs, faked or otherwise. Sadly there is a lot we do not know about the secret Nazi aircraft programs, and barring rumor and speculation we have to rely on what we know now of modern aircraft design. Now, wherein the special projects craft may or may not be inspired by or applying actual non-terrestrial technologies, that’s for history to say. I'll stick to being a UFO historian and leave the arguments as to whether or not something exists or may have existed to those who have their hands on such craft at places like the much mentioned Area 51, the facilities near Salt Lake City, Utah and at the alleged facilities near Tulsa, Oklahoma. Furthermore, Ovni-the-UFO I invite you to contact me, please - as this is not really the place to have a drawn out discussion on such things.
Ovni-the-UFO Featured By Owner Jan 25, 2010
Ah, ok.
bagera3005 Featured By Owner Jan 21, 2010  Professional Interface Designer
Aurora more than one bird type
Peebo-Thulhu Featured By Owner Jan 21, 2010
AH! I see, so you are proposing that this craft uses a working model of the failed "Linear air-o-spike" rocket type motor (Or some sort of air breathing hybrid type affair) that NASA couldn't get working for, um, the X-35? I think it was.

It couldn't be that sneaky if every man and his dog can see it glowing in the infra-red...';P
vharshyde Featured By Owner Jul 15, 2013
You're referring to the X-33, and the X-33 did not fail based on the Linear Aerospike. In fact, the engines met and exceeded expectations, even though the contractor insisted on using a heavier material than anticipated. The weight was compensated for in terms of the engineers discovering that the proposed composite fuel tanks would not have survived deep freeze, so they went with what was thought to be a heavier Al-Li standard alloy(as used at the time on the Shuttle), only to discover that due to the structure of the tanks themselves, the weight was significantly reduced. Additionally, the heat shields used by the X-33 prior to decommission could be put to use here as well, though there are a number of other problems here that I'll address at another time.
EagleDrummer17 Featured By Owner Jun 24, 2013
Made people constantly mistake it for a meteor? Hah
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