If its fuselage, tail, and engine nacelles contribute nothing to an aircraft's lift, why not get rid of them?
Designers pursued the all-wing dream from the first decade of powered flight, notably Jack Northrop in the U.S. and the Horten brothers in Germany. Reimar and Walter Horten were a step ahead, testing an all-wing sailplane in 1933, a twin-engined pusher in 1937, and a turbojet fighter-bomber in 1944. When the war ended, Reimar was working on a six-engine "Amerika Bomber" to carry a hypothetical atomic bomb to New York City.
Postwar, the western Allies dismissed their work, though the British toyed with a transport version of the Amerika Bomber. Walter stayed in Germany and eventually rejoined the Luftwaffe; Reimar went to Argentina and worked for the Peron government.
Meanwhile, Jack Northrop was still trying to build a successful all-wing turbojet bomber in the 1950s. That he never hired the Hortens, who as German engineers were recruited for the U.S. space program, may have been one of history's great missed opportunities.
In the end, all that came from their work was a dozen aircraft whose beauty still astonishes. This is especially true of the Ho 229 fighter-bomber, a bat like warplane that would not look out of place at a 21st-century air show--or combat airfield.
Ho I - 1931 - a flying-wing sailplane.
Ho II - 1934 - initially a glider, it fitted with a pusher propeller in 1935. Looked very like Northrop's flying wings.
Ho III - 1938 - a metal-frame glider, later fitted with a folding-blade [folded while gliding] propeller for powered flight.
Ho IV - 1941 - a high-aspect-ratio glider [looking very like a modern sailplane, but without a long tail or nose].
Ho V - 1937-42 - first Horten plane designed to be powered, built partially from plastics, and powered by two pusher propellers.
Ho VI "Flying Parabola" - an extremely-high-aspect-ratio test- only glider. [After the war, the Ho VI was shipped to Northrop for analysis].
Ho VII - 1945 - considered the most flyable of the powered Ho series by the Horten Brothers, it was built as a flying-wing trainer. [Only one was built and tested, and 18 more were ordered, but the war ended before more than one additional Ho VII could be even partially completed].
Ho VIII - 1945 - a 158-food wingspan, 6-engine plane built as a transport. Never built. However, this design was "reborn" in the 1950's when Reimar Horten built a flying-wing plane for Argentina's Institute Aerotecnico, which flew on December 9, 1960 -- the project was shelved thereafter due to technical problems.
Ho IX - 1944 - the first combat-intended Horten design, a jet powered [Junkers Jumo 004B's], with metal frame and plywood exterior [due to wartime shortages]. First flew in January 1945, but never in combat. When the Allies overran the factory, the almost-completed Ho IX V3 [third in the series - this plane was also known as the "Gotha Go 229"] was shipped back to the Air and Space Museum.
Four aircraft of the Ho IX type were started, designated V.1 to V.4. The V.1 and V.2 were built at Göttigen, designed to carry two BMW 003 jet engines.
V.2 was built with two Juno 004 [jet] engines and had two hours flying before crashing during a single-engine landing. The test pilot, Erwin Ziller, apparently landed short after misjudging his approach.
V.3 was built by Gotha at Friedrichsrodal as a prototype of the senior production version.
V.4 was designed to be a two-man night fighter, with a stretched nose in the fuselage to accommodate the second crewman.
The Horten Ho 229 [often erroneously called Gotha Go 229 due to the identity of the chosen manufacturer of the aircraft] was a late-World War II flying wing fighter aircraft, designed by the Horten brothers and built by the Gothaer Waggonfabrik. It was a personal favourite of Reichsmarschall Hermann Göring, and was the only plane to be able to meet his performance requirements.
In the 1930s the Horten brothers had become interested in the all-wing design as a method of improving the performance of gliders. The all-wing layout removes any "unneeded" surfaces and –in theory at least– leads to the lowest possible drag. For a glider low drag is very important, with a more conventional layout you have to go to extremes to reduce drag and you will end up with long and more fragile wings. If you can get the same performance with a wing-only configuration, you end up with a similarly performing glider with wings that are shorter and thus sturdier.
Years later, in 1943 Reichsmarschall Göring issued a request for design proposals to produce a bomber that was capable of carrying a 1000 kg load over 1000 km at 1000 km/h; the so called 1000/1000/1000 rule. Conventional German bombers could reach Allied command centers in England, but were suffering devastating losses, as allied fighter planes were faster than the German bombers. At the time there was simply no way to meet these goals; the new Jumo 004B jet engines could give the speed that was required, but swallowed fuel at such a rate that they would never be able to match the range requirement.
The Hortens felt that the low-drag all-wing design could meet all of the goals – by reducing the drag, cruise power could be lowered to the point where the range requirement could be met. They put forward their current private (and jealously guarded) project, the Ho IX, as the basis for the bomber. The Government Air Ministry (Reichsluftfahrtministerium) approved the Horten proposal, but ordered the addition of two 30MM cannon, as they felt the aircraft would also be useful as a fighter due to its estimated top speed being significantly higher than any allied aircraft.
Reichsmarschall Göring believed in the design and ordered the aircraft into production at Gotha as the RLM designation of Ho 229 before it had taken to the air under jet power. Flight testing of the Ho IX/Ho 229 prototypes began in December 1944, and the aircraft proved to be even better than expected. There were a number of minor handling problems but otherwise the performance was outstanding.
Gotha appeared to be somewhat upset about being ordered to build a design from two "unknowns" and made a number of changes to the design, as well as offering up a number of versions for different roles. Several more prototypes, including those for a two-seat 'Nacht-Jäger' night fighter, were under construction when the Gotha plant was overrun by the American troops in April of 1945.
The Gotha factory also was building the radar-equipped Horten Ho IX, a for that time futuristic jet-engine flying wing. Using the knowledge they gathered from the construction of these now named Gotha Go 229 [the other name used for the Horten Ho IX], they made a proposal for a fighter, the Gotha P60. The P60 used nearly the same wing layout as the Go 229. The first proposal, the P60A, used a cockpit with the crew  in a prone position laying side-to-side.
The engines of the P60A were placed outside the wing. One on top of the central part, one under the central part. Maybe this was done for better maintenance of the engines.
The second proposal, the Gotha P60B, no longer had the prone pilots. It seems to be that Gotha needed to make a simplified cockpit. Maybe they wanted to speed up development or production. Gotha got approval to start building the P60B-prototype, but work was stopped in favor of the final proposal, the P60C.
The Ho 229 A-0 pre-production aircraft were to be powered by two Junkers Jumo 004B turbojets with 1,962 lbf [8.7 kN] thrust each. The maximum speed was estimated at an excellent 590 mph [950 km/h] at sea level and 607 mph [977 km/h] at 39,370 ft [12,000 m]. Maximum ceiling was to be 52,500 ft [16,000 m], although it is unlikely this could be met. Maximum range was estimated at 1180 miles [1,900 km], and the initial climb rate was to be 4330 ft/min (22 m/s). It was to be armed with two 30 mm MK 108 cannon, and could also carry either two 500 kg bombs, or twenty-four R4M rockets.
It was the only design to come close to meeting the 1000/1000/1000 rule, and that would have remained true even for a number of years after the war. But like many of the late war German designs, the production was started far too late for the plane to have any effect. In this case none saw combat.
The majority of the Ho-229's skin was a carbon-impregnated plywood, which would absorb radar waves. This, along with its shape, would have made the Ho-229 invisible to the crude radar of the day. So it should be given credit for being the first true "Stealth Fighter". The US military initiated "Operation Paperclip" which was an effort by the U.S. Army in the last weeks of the war to capture as much advanced German weapons research as possible, and also to deny that research to advancing Russian troops. A Horton glider and the Ho-229 number V2 were secured and sent to Northrop Aviation in the United States for evaluation, who much later used a flying wing design for the B-2 "Spirit" stealth bomber. During WWII Northrop had been commissioned to develop a large wing-only long-range bomber [XB/YB-35] based on photographs of the Horton's record-setting glider from the 1930's, but their initial designs suffered controllability issues that were not resolved until after the war.
The Northrop XB-35 and YB-35 were experimental heavy bomber aircraft developed by the Northrop Corporation for the United States Army Air Forces during and shortly after World War II. The airplane used the radical and potentially very efficient flying wing design, in which the tail section and fuselage are eliminated and all payload is carried in a thick wing. Only prototype and pre-production aircraft were built , but interestingly, the Horten brothers were helped in their bid for German government support when Northrop patents appeared in US Patent Office's "Official Gazette" on 13 May 1941, and then in the International Aeronautical journal "Interavia" on !8 November 1941.
The Northrop YB-49 was a prototype jet-powered heavy bomber aircraft developed by Northrop Corporation shortly after World War II for service with the U.S. Air Force. The YB-49 featured a flying wing design and was a jet-powered development of the earlier, piston-engined Northrop XB-35 and YB-35. The two YB-49s actually built were both converted YB-35 test aircraft.
The YB-49 never entered production, being passed over in favor of the more conventional Convair B-36 piston-driven design. Design work performed in the development of the YB-35 and YB-49 nonetheless proved to be valuable to Northrop decades later in the eventual development of the B-2 stealth bomber, which entered service in the early 1990s.
The YB-49 and its modern counterpart, the B-2 Spirit, both built by Northrop Grumman, have the same wingspan: 172.0 ft [52.4 m]. Flight test data collected from the original YB-49 test flights was used in the development of the B-2 bomber.
The Ho-229's design employed a thoroughly modern wing shape far ahead of its time. The wing had a twist so that in level flight the wingtips [and thus, the ailerons] were parallel with the ground. The center section was twisted upwards, which deflected air in flight, and provided the majority of its lift. Because of this twist in its shape, If the pilot pulled up too suddenly, the nose would stall [or, lose lift] before the wingtips. This meant that the craft's nose would inherently dip in the beginnings of a stall causing the plane to accelerate downwards, and thus it would naturally avoid a flat spin. A flat spin is difficult to recover from, and many rookie pilots have crashed from this condition. Horten also noticed in wind-tunnel testing that in the beginnings of a stall, most airfoil cross-sections began losing lift on their front and rear edges first. Horten designed an airfoil cross-section that developed most of its lift along the centerline of the wing. Since the center line had high lift and the front and rear edges had low lift, it was called a "Bell-Shaped lift curve". The wings were also swept back at a very modern and optimum angle [his gliders from the 1930's used this sweep long before it became popular] which enhanced its stall-resistance, and also lowered its wind-resistance which helped its top speed. This made the Ho-229 easy to fly and very stall-resistant in all phases of its operation.
The only existing Ho-229 airframe to be preserved was V2, and it is located at the National Air and Space Museum [NASM] in Washington D.C. The airframe V1 crashed during testing, and several partial airframes found on the assembly line were destroyed by U.S. troops to prevent them from being captured by advancing Russian troops.
In 1944 the RLM issued a requirement for an aircraft with a range of 11000 km [6835 miles] and a bomb load of 4000 kg [8818lbs]. This bomber was to be able to fly from Germany to New York City and back without refuelling. Five of Germany's top aircraft companies had submitted designs, but none of them met the range requirements for this Amerika Bomber. Their proposals were redesigned and resubmitted at the second competition, but nothing had changed. The Hortens were not invited to submit a proposal because it was thought that they were only interested in fighter aircraft.
After the Hortens learned of these design failures, they went about designing the XVIIIA Amerika Bomber. During the Christmas 1944 holidays, Reimar and Walter Horten worked on the design specifications for their all-wing bomber. They drew up a rough draft and worked on weight calculations, allowing for fuel, crew, armaments, landing gear and bomb load. Ten variations were eventually worked out, each using a different number of existing turbojets. Several of the designs were to be powered by four or six Heinkel-Hirth He S 011jet engines, and several of the others were designed around eight BMW 003A or eight Junker Jumo 004B turbojets.
The version that the Hortens thought would work best would utilize six Jumo 004B turbojets, which were buried in the fuselage and exhausted over the rear of the aircraft. They were fed by air intakes located in the wing's leading edge. To save weight they thought of using a landing gear that could be jettisoned immediately after takeoff [with the additional help of rocket boosters] and landing on some kind of skid. The Ho XVIII A was to be built mainly of wood and held together with a special carbon based glue. As a result, the huge flying wing should go largely undetected by radar.
The Hortens were told to make a presentation for their Amerika Bomber design on 25 February 1945 in Berlin. The meeting was attended by representatives of the five aircraft companies who originally submitted ideas for the competition. No one challenged their assertion that their flying wing bomber could get the job done. A few days later the Hortens were told to report to Reichsmarshall Göring, who wanted to talk to the brothers personally about their proposed Amerika Bomber. There they were told that they were to work with the Junkers company in building the aircraft.
Several days later Reimar and Walter Horten met with the Junkers engineers, who had also invited some Messerschmitt engineers. Suddenly it seemed that the Horten's design was to be worked on by committee. The Junkers and Messerschmitt engineers were unwilling to go with the design that the Hortens had presented several days earlier. Instead, the committee wanted to place a huge vertical fin and rudder to the rear of the Ho XVIII A. Reimar Horten was angry, as this would add many more man-hours, plus it would create drag and thus reduce the range. The committee also wanted to place the engines beneath the wing, which would create additional drag and reduce the range even further. After two days of discussion, they chose a design that had huge vertical fins, with the cockpit built into the fin's leading edge. Six Jumo 004A jet engines were slung under the wing, three to a nacelle on each side. The bomb bay would be located between the two nacelles, and the tricycle landing gear would also be stored in the same area. The committee would present the final design to the RML and recommended that it be built in the former mining tunnels in the Harz Mountains.
Dissatisfied with the committee designed Ho XVIII A, Reimar Horten redesigned the flying wing Amerika Bomber. The proposed Ho XVIII B had a three man crew which sat upright in a bubble-type canopy near the apex of the wing. There were two fixed main landing gear assemblies with two He S 011 turbojets mounted to each side.
During flight, the tires would be covered by doors to help cut down on air resistance and drag, a nose wheel being considered not necessary. Overall, the aircraft would have weighed about 35 tons fully loaded. Fuel was to be stored in the wing so that no auxiliary fuel tanks would be required. It was estimated that the Ho XVIII B would have a range of 11000 km [6835 miles], a service ceiling of 16 km [52492 feet] and a round-trip endurance of 27 hours.
It was decided that construction was to be done in two bomb-proof hangers near Kala, which had concrete roofs 5.6 meters [18.4 feet] thick. In addition, extra long runways had been constructed so the aircraft could be test flown there too. Work was supposed to start immediately, and the RLM expected the Ho XVIII B to be built by the fall of 1945, which Reimar Horten reported to be impossible. At any rate, Germany surrendered two months later before construction could begin.
In 1943 the all-wing Horten 229 promised spectacular performance and the Luftwaffe [German Air Force] chief, Hermann Göring, allocated half-a-million Reich Marks to the brothers Reimar and Walter Horten to build and fly several prototypes. Numerous technical problems beset this unique design and the only powered example crashed after several test flights but the airplane remains one of the most unusual combat aircraft tested during World War II. Horten used Roman numerals to identify his designs and he followed the German aircraft industry practice of using "Versuch," literally test or experiment, numbers to describe pre-production prototypes built to test and develop a new design into a production airplane. The Horten IX design became the Horten Ho 229 aircraft program after Göring granted the project official status in 1943 and the technical office of the Reichsluftfahrtministerium assigned to it the design number 229. This is also the nomenclature used in official German documents.
The idea for the Horten IX grew first in the mind of Walter Horten when he was serving in the Luftwaffe as a fighter pilot engaged in combat in 1940 during the Battle of Britain. Horten was the technical officer for Jadgeschwader [fighter squadron] 26 stationed in France. The nature of the battle and the tactics employed by the Germans spotlighted the design deficiencies of the Messerschmitt Bf 109, Germany's most advanced fighter airplane at that time. The Luftwaffe pilots had to fly across the English Channel or the North Sea to fulfill their missions of escorting German bombers and attacking British fighters, and Horten watched his unit lose many men over hostile territory at the very limit of the airplane's combat radius. Often after just a few minutes flying in combat, the Germans frequently had to turn back to their bases or run out of fuel and this lack of endurance severely limited their effectiveness. The Messerschmitt was also vulnerable because it had just a single engine. One bullet could puncture almost any part of the cooling system and when this happened, the engine could continue to function for only a few minutes before it overheated and seized up.
Walter Horten came to believe that the Luftwaffe needed a new fighter designed with performance superior to the Supermarine Spitfire, Britain's most advanced fighter. The new airplane required sufficient range to fly to England, loiter for a useful length of time and engage in combat, and then return safely to occupied Europe. He understood that only a twin-engine aircraft could give pilots a reasonable chance of returning with substantial battle damage or even the loss of one engine.
Since 1933, and interrupted only by military service, Walter and Reimar had experimented with all-wing aircraft. With Walter's help, Reimar had used his skills as a mathematician and designer to overcome many of the limitations of this exotic configuration. Walter believed that Reimar could design an all-wing fighter with significantly better combat performance than the Spitfire. The new fighter needed a powerful, robust propulsion system to give the airplane great speed but also one that could absorb damage and continue to function.
The Nazis had begun developing rocket, pulse-jet, and jet turbine configurations by 1940 and Walter's role as squadron technical officer gave him access to information about these advanced programs. He soon concluded that if his brother could design a fighter propelled by two small and powerful engines and unencumbered by a fuselage or tail, very high performance was possible.
At the end of 1940, Walter shared his thoughts on the all-wing fighter with Reimar who fully agreed with his brother's assessment and immediately set to work on the new fighter. Fiercely independent and lacking the proper intellectual credentials, Reimar worked at some distance from the mainstream German aeronautical community. At the start of his career, he was denied access to wind tunnels due to the cost but also because of his young age and lack of education, so he tested his ideas using models and piloted aircraft. By the time the war began, Reimar actually preferred to develop his ideas by building and testing full-size aircraft. The brothers had already successfully flown more than 20 aircraft by 1941 but the new jet wing would be heavier and faster than any previous Horten design. To minimize the risk of experimenting with such an advanced aircraft, Reimar built and tested several interim designs, each one moderately faster, heavier, or more advanced in some significant way than the one before it.
Reimar built the Horten Vb and Vc to evaluate the all-wing layout when powered by twin engines driving pusher propellers. He began in 1941 to consider fitting the Dietrich-Argus pulse jet motor to the Horten V but this engine had drawbacks and in the first month of 1942, Walter gave his brother dimensioned drawings and graphs that charted the performance curves of the new Junkers 004 jet turbine engine [this engine was also fitted to these NASM aircraft: Messerschmitt Me 262, Arado Ar 234, and the Heinkel He 162]. Later that year, Reimar flew a new design called the Horten VII that was similar to the Horten V but larger and equipped with more powerful reciprocating engines. The Horten VI ultra-high performance sailplane also figured into the preliminary aerodynamic design of the jet flying wing after Reimar tested this aircraft with a special center section.
Walter used his personal connections with important officials to keep the idea of the jet wing alive in the early stages of its development. General Ernst Udet, Chief of Luftwaffe Procurement and Supply and head of the Technical Office was the man who protected this idea and followed this idea for the all-wing fighter for almost a year until Udet took his own life in November 1941. At the beginning of 1943, Walter heard Göring complain that Germany was fielding 17 different types of twin-engine military airplanes with similar, and rather mediocre, performance but parts were not interchangeable between any two designs. He decreed that henceforth he would not approve for production another new twin-engine airplane unless it could carry 1,000 kg [2,210 lb] of bombs to a "penetration depth" of 1,000 km [620 miles, penetration depth defined as 1/3 the range] at a speed of 1,000 km/h [620 mph]. Asked to comment, Reimar announced that only a warplane equipped with jet engines had a chance to meet those requirements.
In August Reimar submitted a short summary of an all-wing design that came close to achieving Göring's specifications. He issued the brothers a contract, and then demanded the new aircraft fly in 3 months. Reimar responded that the first Horten IX prototype could fly in six months and Göring accepted this schedule after revealing his desperation to get the new fighter in the air with all possible speed. Reimar believed that he had boosted the Reichsmarschall's confidence in his work after he told him that his all-wing jet bomber was based on data obtained from bona fide flight tests with piloted aircraft.
Official support had now been granted to the first all-wing Horten airplane designed specifically for military applications but the jet bomber that the Horten brothers began to design was much different from the all-wing pure fighter that Walter had envisioned nearly four years earlier as the answer to the Luftwaffe's needs for a long-range interceptor. Hencefourth, the official designation for airplanes based on the Horten IX design changed to Horten Ho 229 suffixed with "Versuch" numbers to designate the various prototypes.
All versions of the Ho 229 resembled each other in overall layout. Reimar swept each half of the wing 32 degrees in an unbroken line from the nose to the start of each wingtip where he turned the leading edge to meet the wing trailing edge in a graceful and gradually tightening curve. There was no fuselage, no vertical or horizontal tail, and with landing gear stowed [the main landing gear was fixed but the nose wheel retracted on the first prototype Ho 229 V1], the upper and lower surface of the wing stretched smooth from wingtip to wingtip, unbroken by any control surface or other protuberance. Horten mounted elevons [control surfaces that combined the actions of elevators and ailerons] to the trailing edge and spoilers at the wingtips for controlling pitch and roll, and he installed drag rudders next to the spoilers to help control the wing about the yaw axis. He also mounted flaps and a speed brake to help slow the wing and control its rate and angle of descent. When not in use, all control surfaces either lay concealed inside the wing or trailed from its aft edge. Parasite or form drag was virtually nonexistent. The only drag this aircraft produced was the inevitable by-product of the wing's lift.
Few aircraft before the Horten 229 or after it have matched the purity and simplicity of its aerodynamic form but whether this achievement would have led to a successful and practical combat aircraft remains an open question.
Building on knowledge gained by flying the Horten V and VII, Reimar designed and built a manned glider called the Horten 229 V1 which test pilot Heinz Schiedhauer first flew 28 February 1944. This aircraft suffered several minor accidents but a number of pilots flew the wing during the following months of testing at Oranienburg and most commented favorably on its performance and handling qualities. Reimar used the experience gained with this glider to design and build the jet-propelled Ho 229 V2.
Wood is an unorthodox material from which to construct a jet aircraft and the Horten brothers preferred aluminum but in addition to the lack of metalworking skills among their team of craftspersons, several factors worked against using the metal to build their first jet-propelled wing.
Reimar's calculations showed that he would need to convert much of the wing's interior volume into space for fuel if he hoped to come close to meeting Göring's requirement for a penetration depth of 1,000 km. Reimar must have lacked either the expertise or the special sealants to manufacture such a 'wet' wing from metal. Whatever the reason, he believed that an aluminum wing was unsuitable for this task. Another factor in Reimar's choice of wood is rather startling: he believed that he needed to keep the wing's radar cross-section as low as possible. "We wished", he said many years later, "to have the [Ho 229] plane that would not reflect [radar signals]", and Horten believed he could meet this requirement more easily with wood than metal. Many questions about this aspect of the Ho 229 design remain unanswered and no test data is available to document Horten's work in this area. The fragmentary information that is currently available comes entirely from anecdotal accounts that have surfaced well after World War II ended.
During the war, the Germans experimented with tailless, flying wing aircraft.
The ones described here were made by the Horten brothers. There were several flying wing designs under development during those years for various purposes but the one in question is the Horton iX.
The Horten ix was a tailless, jet-powered, flying wing fighter. Only three were ever built. The first Horton IXx [V-1] was never given engines and used as a glider for test purposes. The second Horton IX [V-2] was given jets and tested. The third aircraft was actually produced by another company, the Gotha firm who was to mass-produce this aircraft. This one aircraft was given the designation Gotha 229 and was never fully assembled and never flew. It fell into the hands of the Americans while still in pieces.
So, it was only the second Horten iX, the V-2 version that flew at all. In fact, it flew very well. Remember, this was a tailless flying wing that flew before computer avionics made such aircraft possible in the USA. Evidently, the Horten iX was so well thought out that a mere human pilot could fly it. But the Horton IX was somewhat more than just an ordinary fighter aircraft. During flight testing it was noticed that the radar return for this aircraft was almost absent. The Germans got busy with this idea and planned to paint the Horten IX with radar absorbing paint that they had developed for another purpose. The fact is that the Horten ix was the world's first stealth aircraft. Unfortunately, during a landing one of its two engines failed and the one flying Horton IX crashed.
So what do we know about the Horten IX in flight? All we now know about the performance of this legendary aircraft is what Allied technical teams said about it and this is the way it has been reported to us down through history via semi technical aircraft history journals and books.
For instance David Masters, in his book "German Jet Genesis", lists the speed of the Horten IX at 540 mph with a ceiling altitude of 52,490 feet. The same authority reports the Gotha 229 [which never flew] as having a maximum speed of 590 mph at sea level and 640 mph at 21,320 ft. with a ceiling of 51,000 ft. This compares with the Me 262, the operational German jet fighter with which we are familiar, whose top speed Masters lists at 538 mph at 29,560 ft. with no ceiling given.
Surprisingly, both jets were powered by the same two Junkers Jumo 004B-1 engines. Yet the Horten 9 had the cross-section of a knife while the Messerschmitt cross-section was much more typical for an aircraft of the time. How could their performance be nearly identical? How would the Allies know what the performance of the Horten IX actually was since they never got their hands on a working example?
Perhaps it was extrapolation. Perhaps they simply wanted to under value this sleek German jet simply because it looked so advanced for its time and there was nothing comparable in the Allied arsenal. Without contradictory evidence, the word of the American experts was repeated and became part of history as we know it. The funny thing is that now contradictory evidence has surfaced and has somehow slipped by the American censors.
The document in question is a Memorandum Report, dated 17 March 1945 while the war was still in progress. The "Subject" of this report was data obtained on the German tailless jet propelled fighter and Vereinigte Leichtmetalwerke [United Light-Metal Works].
"To present data of immediate value obtained on C.I.O.S. trip to Bonn on 11 March to 16 March 1945. Travel performed under AG 200m 4-1, SHAEF, dated 9 March 1945".
There was discussion of the Horton IX in which a maximum speed of 1,160 km/hr or about 719 miles per hour was claimed. The informant spoke during the war, while the last example of the Horton IX was still flying. Data about all other German aircraft is correct. Was there an intentional cover up concerning the performance of the Horton IX by the Allies?
This is raw Intelligence to be compiled into a Combined Intelligence Objectives Sub-Committee report by SHAEF personnel.
Under "Factual Data" we learn that their German informant, Mr. F.V. Berger, is a draftsman for the Horten organization during the time that the Hortons were designing the tailless aircraft. To add to Berger's trusted position, he was actually found in the former home of Horten brothers by the Intelligence agents.
Mr. Berger describes the Horten aircraft, models H1 to H12 but most of the discussion centers on the H9, the jet-powered, tailless, flying wing fighter-bomber.
Berger goes on to list the weight, bomb load and cannons used but then states that the maximum speed for the H9, which was still being tested as this report was being written, was 1,160 km/her at an altitude of 6,000 meters.
This last statement must have shocked the SHAEF team to the core. The speed given, 1,160 kilometers per hour works out to slightly over 719 miles per hour!
The Allies weren't even thinking about flying that fast in those days.
The Intelligence team was transfixed by Berger's statement and double-checked his veracity. They asked him about the speed of the Me 262 and the Arado 234. Allied intelligence knew both these operational German aircraft and their capabilities by this time even if they had not gained an example of each aircraft.
Berger gave the speed of the Me 262 at 900 km/hr and the Arado 234 [jet-powered bomber-reconnaissance aircraft] at 800 km/hr. This works out to 558 mph for the Messerschmitt and 496 mph for the Arado. These figures are right on the money and lend credibility to Berger's evaluation of the Horton IX.
Then Berger made another astonishing statement. Berger stated that the Horton IX, loaded with bombs [weighing 2,000 kg.] "would get away from Me262 without bombs".
Berger went on to describe the Horten IX V-1 correctly as being tested as a glider and the Horton IX V-2 as a fully powered aircraft. He goes on to say that the Horten 9 V-2 "is being tested at Oranienbueg now".
So at the time of this interview, the Horten IX V-2 was still flying and had not crashed yet.
The Horten 9/Gotha 229 had a low radar return. The Germans knew this and planned a radar repelling type of paint for it that was already used on submarines. These features would make the Horton iX the first stealth aircraft, a fact much mentioned concerning the history of the American B-2 bomber. In fact, American engineers visited the remaining partially assembled Gotha 229 in Maryland to get ideas for the B-2.
But the speed given by Berger, 719 miles per hour, puts the Horton IX in a class by itself. By this it is meant that this speed and ceiling altitude exceed both the Soviet Mig 15 and the American F86 'Sabre' of Korean War vintage, five or six years later.
If we listen, we can hear echoes of the undervaluation of German aircraft at the highest levels, even within the American aerospace industry. Aircraft legend Howard Hughes owned a captured Me 262. Hughes was a big fan and participant in something called aircraft racing during those post-war years. Towering pylons would mark out a course of several miles in the California desert and aircraft would race around this course. When Hughes' rival company, North American Aviation came out with its F-86 'Sabre', Howard Hughes challenged the US Air Force to a one-on-one match race of their new 'Sabre' jet against his old German Me 262. The Air Force declined. Obviously, there is some unspoken fact behind the Air Force decision.
The 'Sabre' was said to be "trans-sonic" or having a top speed of about 650 mph, with a ceiling of 45,000 ft. If the US Air Force wanted no part of a contest with the real Me 262, not the paper projection, what would they have thought of a head to head match with the Horton iX?
Yet, the Horton IX was a stealth aircraft. The Americans didn't even recognize what a stealth aircraft was until over 30 years later and even then they always wanted to couch the comparison of the Horton IX to the B-2 stealth bomber. That comparison is fallacious and perhaps designed to hide something else.
Let's compare the Horten 9 to the F-117 stealth fighter instead. The F-117 has vertical control surfaces and may be, in fact, less stealthy than the Horton IX. Both had special radar absorbing paint. But the F-117 is not supersonic. The F-117 is generally conceded to fly about 650 mph, about the same as the F-86 'Sabre', while the Horton 9 could be faster at 719 mph. Another difference is that the Horton IX carried two 37 mm cannons while the F-117 has no guns or rockets and so is really not a fighter at all but only a first-strike bomber.
There are other examples but we should both watch for these tactics and recognize that the government is reluctant to fully credit the Germans for their advances during the war and we should recognize that they will go to some lengths to maintain the secrecy status quo. These tactics also include false comparisons and outright deception.
The Flugfunk Forschungsinstitut Oberpfaffenhofen, abbreviated F.F.O. The F.F.O. was a pure research organization specializing in aeronautical radio research for the Luftwaffe. This organization seems to have specialized in work of jamming radar. This was a large organization and had many physical sites of operation. When the war drew to a conclusion, all the secret research done at the F.F.O. was burnt. What we know and what remains consist largely of what was remembered by the individual scientists involved and their private libraries. It is not unreasonable to assume that some secrets went forever unspoken after those ashes cooled, however.
The F.F.O. developed several types of klystrons. A klystron tube is used to produce ultra-high frequencies and was employed to generate frequencies in order to jam radar.
"Measurement on the conductivity and dielectric properties of flame gases are being conducted by Dr. Lutze at Seeshaupt. They are intended to provide knowledge of the effects to be expected with radio control of rockets and to say how much the flame and trail of a V-2 contributes to radar reflections".
So the F.F.O. was measuring the conductivity and radar reflectional properties of exhaust gases? Placing a cathode in the exhaust of a jet or rocket was the Flame Jet Generator of Dr. T.T. Brown. This procedure induced a negative charge to the exhaust. A corresponding positive charge is automatically induced on the wing's leading edge. This combination bends radar signals around the aircraft and is one method used by the B-2 bomber.
The Horton IX, had recessed intake and exhaust ports. It had no vertical control surfaces. Therefore, its radar reflection was already super-low. There is no trouble imagining this aircraft painted with radar absorbing paint as was planned, but how about inducing a radar-bending envelope of charged particles around this aircraft? And how about fitting this aircraft with a klystron tube in its nose pumping out the same frequency used by Allied radar, jamming it or making the aircraft invisible to radar? If we can imagine this, so could the scientists with the F.F.O. If the war had lasted another year, the Allies might have faced not only a 700 mile per hour Horton IX, but a Horton IX which was also a true stealth aircraft in the modern sense.
-- Henry Stevens, "Hitler's Suppressed and Still-Secret Weapons, Science and Technology"
As they developed the 229, the Horten brothers measured the wing's performance against the Messerschmitt Me 262 jet fighter. According to Reimar and Walter, the Me 262 had a much higher wing loading than the Ho 229 and the Messerschmitt required such a long runway for take off that only a few airfields in Germany could accommodate it. The Ho 229 wing loading was considerably lower and this would have allowed it to operate from airfields with shorter runways. Reimar also believed, perhaps naively, that his wing could take off and land from a runway surfaced with grass but the Me 262 could not. If these had been true, a Ho 229 pilot would have had many more airfields from which to fly than his counterpart in the Messerschmitt jet.
Successful test flights in the Ho 229 V1 led to construction of the first powered wing, the Ho 229 V2, but poor communication with the engine manufacturers caused lengthy delays in finishing this aircraft. Horten first selected the 003 jet engine manufactured by BMW but then switched to the Junkers 004 power plants. Reimar built much of the wing center section based on the engine specifications sent by Junkers but when two motors finally arrived and Reimar's team tried to install them, they found the power plants were too large in diameter to fit the space built for them. Months passed while Horten redesigned the wing and the jet finally flew in mid-December 1944.
Full of fuel and ready to fly, the Horten Ho 229 V2 weighed about nine tons and thus it resembled a medium-sized, multi-engine bomber such as the Heinkel He 111. The Horten brothers believed that a military pilot with experience flying heavy multi-engine aircraft was required to safely fly the jet wing and Scheidhauer lacked these skills so Walter brought in veteran Luftwaffe pilot Lt. Erwin Ziller. Sources differ between two and four on the number of flights that Ziller logged but during his final test flight an engine failed and the jet wing crashed, killing Ziller.
According to an eyewitness, Ziller made three passes at an altitude of about 2,000 m [6,560 ft] so that a team from the Rechlin test center could measure his speed using a theodolite measuring instrument. Ziller then approached the airfield to land, lowered his landing grear at about 1,500 m [4,920 ft], and began to fly a wide descending spiral before crashing just beyond the airfield boundary. It was clear to those who examined the wreckage that one engine had failed but the eyewitness saw no control movements or attempt to line up with the runway and he suspected that something had incapacitated Ziller, perhaps fumes from the operating engine. Walter was convinced that the engine failure did not result in uncontrollable yaw and argued that Ziller could have shut down the functioning engine and glided to a survivable crash landing, perhaps even reached the runway and landed without damage.
Walter also believed that someone might have sabotaged the airplane but whatever the cause, he remembered it was an awful event. "All our work was over at this moment". The crash must have disappointed Reimar as well. Ziller's test flights seemed to indicate the potential for great speed, perhaps a maximum of 977 km/h [606 mph]. Although never confirmed, such performance would have helped to answer the Luftwaffe technical experts who criticized the all-wing configuration.
At the time of Ziller's crash, the Reich Air Ministry had scheduled series production of 15-20 machines at the firm Gotha Waggonfabrik Flugzeugbau and the Klemm company had begun preparing to manufacture wing ribs and other parts when the war ended.
Horten had planned to arm the third prototype with cannons but the war ended before this airplane was finished. Unbeknownst to the Horten brothers, Gotha designers substantially altered Horten's original design when they built the V3 airframe. For example, they used a much larger nose wheel compared to the unit fitted to the V2 and Reimar speculated that the planned 1,000 kg [2,200 lb] bomb load may have influenced them but he believed that all of the alterations that they made were unnecessary.
The U.S. VIII Corps of General Patton's Third Army found the Horten 229 prototypes V3 through V6 at Friedrichsroda in April 1945. Horten had designed airframes V4 and V5 as single-seat night fighters and V6 would have become a two-seat night fighter trainer. V3 was 75 percent finished and nearest to completion of the four airframes. Army personnel removed it later and shipped it to the U.S., via the Royal Aircraft Establishment at Farnborough, England. Reports indicate the British displayed the jet during fall 1945 and eventually the incomplete center section arrived at Silver Hill [now the Paul E. Garber Facility in Suitland, Maryland] about 1950.
There is no evidence that the outer wing sections were recovered at Friedrichsroda but members of the 9th Air Force Air Disarmament Division found a pair of wings 121 km [75 miles] from this village and these might be the same pair now included with the Ho 229 V3.
Reimar and Walter Horten demonstrated that a fighter-class all-wing aircraft could successfully fly propelled by jet turbine engines but Ziller's crash and the end of the war prevented them from demonstrating the full potential of the configuration.
The wing was clearly a bold and unusual design of considerable merit, particularly if Reimar actually aimed to design a "Stealth Bomber" but as a tailless fighter-bomber armed with massive 30mm cannon placed wide apart in the center section, the wing would probably have been a poor gun platform and found little favor among fighter pilots.
Walter argued rather strenuously with his brother to place a vertical stabilizer on this airplane.
Like most of the so-called "Nazi wonder weapons" the Horten IX was an interesting concept that was poorly executed.
One of Reimar Horten's projects after the war began was an all-wing transport glider for the invasion of Britain.
Not until August 1941 was Reimar asked to explore the potential of the Nurflügel as a fighting aircraft, and even then his work was largely clandestine, in an authorized operation arranged by his brother in the Luftwaffe.
In 1942 Reimar built an unpowered prototype with a 61-foot span and the designation Ho 9. After some difficulty the airframe was mated with two Junkers Jumo turbojets of the sort developed for the Messerschmitt Me 262. The turbojet was apparently flown successfully in December 1944, and it eventually achieved a speed of nearly 500 mph [800 km/h]. After about two hours of flying time, it was destroyed in a February 1945 crash that killed its test pilot.
Its potential was obvious, however, and the Gotha company promptly readied the turbojet for production as a fighter-bomber with the Air Ministry designation Ho 229. [Because Gotha built it, the turbojet is also called the Go 229].
Supposedly it would fly at 997 km/h [623 mph], which if true meant that it was significantly faster than the Me 262 - let alone the Flying Wings that Northrop was building. Fortunately for the Allies, the Gotha factory and the Ho 229 prototype -the world's first all-wing turbojet- were captured by U.S. forces in April 1945.
Like today's B-2 Stealth bomber [and unlike Jack Northrop's designs], the Go-229 had a comparatively slender airfoil, with the crew and engines housed in dorsal humps, and its jet exhaust was vented onto the top surface of the wing. The first feature made it faster than the stubby Northrop designs; the second made it even harder to detect, as did the fact that wood was extensively used in its construction.
One reason that the Ho 229 never got into production was that Reimar Horten was distracted that winter by another urgent project: The Ho 18 Amerika bomber.
This huge, six-engined Nurflügel was supposed to carry an atomic bomb to New York or Washington, despite the fact that the bomb was mostly theoretical, the engines probably couldn't have lasted the journey, and the plane couldn't possibly have been completed before Germany surrendered.
[At 132 feet, its span was a bit less than that of the Boeing B-29 Superfortress, the largest warplane of World War II, but considerably shorter than the Northrop XB-35 that was in the works from 1941 to 1946].
Several Nurflügels came to the U.S. as war booty, including the center section of the Ho 229.
Four of them are now back in Germany for restoration, with one to remain there when the work is finished, while the other three rejoin the collection of the Air & Space Museum.
A restored Horten sailplane is on display at Planes of Fame in Chino, California, which also owns a Northrop N-9M, a technology demonstrator roughly the size of the Ho 229, but much less sophisticated.
It was nighttime on the Rio Grande, 29 May 1947, and Army scientists, engineers, and technicians at the White Sands Proving Ground in New Mexico were anxiously putting the final touches on their own American secret weapon, called 'Hermes'. The twenty-five-foot-long, three-thousand-pound rocket had originally been named V-2, or Vergeltungswaffe 2, which means "vengeance" in German. But 'Hermes' sounded less spiteful; Hermes being the ancient Greek messenger of the gods.
The actual rocket that now stood on Test Stand 33 had belonged to Adolf Hitler just a little more than two years before. It had come off the same German slave-labor production lines as the rockets that the Third Reich had used to terrorize the people of London, Antwerp, and Paris during the war. The U.S. Army had confiscated nearly two hundred V-2s from inside Peenemünde, Germany's rocket manufacturing plant, and shipped them to White Sands beginning the first month after the war. Under a parallel, even more secret project called "Operation Paperclip" the complete details of which remain classified as of 2011, 118 captured German rocket scientists were given new lives and careers and brought to the missile range. Hundreds of others would follow.
Two of these German scientists were now readying 'Hermes' for its test launch. One, Wernher Von Braun, had invented this rocket, which was the world's first ballistic missile, or flying bomb. And the second scientist, Dr. Ernst Steinhoff, had designed the V-2 rocket's brain. That spring night in 1947, the V-2 lifted up off the pad, rising slowly at first, with von Braun and Steinhoff watching intently. 'Hermes' consumed more than a thousand pounds of rocket fuel in its first 2.5 seconds as it elevated to fifty feet. The next fifty feet were much easier, as were the hundred feet after that. The rocket gained speed, and the laws of physics kicked in: Aything can fly if you make it move fast enough. 'Hermes' was now fully aloft, climbing quickly into the night sky and headed for the upper atmosphere. At least that was the plan. Just a few moments later, the winged missile suddenly and unexpectedly reversed course. Instead of heading north to the uninhabited terrain inside the two-million-square-acre White Sands Proving Ground, the rocket began heading south toward downtown El Paso, Texas.
Dr. Steinhoff was watching the missile's trajectory through a telescope from an observation post one mile south of the launchpad, and having personally designed the V-2 rocket-guidance controls back when he worked for Adolf Hitler, Dr. Steinhoff was the one best equipped to recognize errors in the test. In the event that Steinhoff detected an errant launch, he would notify Army engineers, who would immediately cut the fuel to the rocket's motors via remote control, allowing it to crash safely inside the missile range. But Dr. Steinhoff said nothing as the misguided V-2 arced over El Paso and headed for Mexico. Minutes later, the rocket crash-landed into the Tepeyac Cemetery, three miles south of Juarez, a heavily populated city of 120,000. The violent blast shook virtually every building in El Paso and Juarez, terrifying citizens of both cities, who swamped newspaper offices, police headquarters and radio stations with anxious telephone inquiries. The missile left a crater that was fifty feet wide and twenty-four feet deep. It was a miracle no one was killed.
Army officials rushed to Juarez to smooth over the event while Mexican soldiers were dispatched to guard the crater's rim. The mission, the men, and the rocket were all classified top secret; no one could know specific details about any of this. Investigators silenced Mexican officials by cleaning up the large, bowl-shaped cavity and paying for damages. But back at White Sands, reparations were not so easily made. Allegations of sabotage by the German scientists who were in charge of the top secret project overwhelmed the workload of the Intelligence officers at White Sands. Attitudes toward the former Third Reich scientists who were now working for the United States tended to fall into two distinct categories at the time. There was the let-bygones-be-bygones approach, an attitude summed up by the Army officer in charge of 'Operation Paperclip', Bosquet Wev, who stated that to preoccupy oneself with "picayune details" about German scientists' past actions was "beating a dead Nazi horse". The logic behind this thinking was that a disbanded Third Reich presented no future harm to America but a burgeoning Soviet military certainly did and if the Germans were working for us, they couldn't be working for them.
Others disagreed, including Albert Einstein. Five months before the Juarez crash, Einstein and the newly formed Federation of American Scientists appealed to President Truman: "We hold these individuals to be potentially dangerous¡ Their former eminence as Nazi party members and supporters raises the issue of their fitness to become American citizens and hold key positions in American industrial, scientific and educational institutions". For Einstein, making deals with war criminals was undemocratic as well as dangerous.
While the public debate went on, internal investigations began. And the rocket work at White Sands continued. The German scientists had been testing V-2s there for fourteen months, and while investigations of the Juarez rocket crash were under way, three more missiles fired from Test Stand 33 crash-landed outside the restricted facility: one near Alamogordo, New Mexico, and another near Las Cruces, New Mexico. A third went down outside Juarez, Mexico, again. The German scientists blamed the near tragedies on old V-2 components. Seawater had corroded some of the parts during the original boat trip from Germany. But in top secret written reports, Army Intelligence officers were building a case that would lay blame on the German scientists. The War Department Intelligence unit that kept tabs on the German scientists had designated some of the Germans at the base as "under suspicion of being potential security risks". When not working, the men were confined to a six-acre section of the base. The officers' club was off-limits to all the Germans, including the rocket team's leaders, Steinhoff and von Braun. It was in this atmosphere of failed tests and mistrust that an extra-ordinary event happened, one that, at first glance, seemed totally unrelated to the missile launches.
During the first week of July 1947, U.S. Signal Corps engineers began tracking two objects with remarkable flying capabilities moving across the southwestern United States. What made the aircraft extra-ordinary was that, although they flew in a traditional, forward-moving motion, the craft, whatever they were, began to hover sporadically before continuing to fly on. This kind of technology was beyond any aerodynamic capabilities the U.S. Air Force had in development in the summer of 1947. When multiple sources began reporting the same data, it became clear that the radar wasn't showing phantom returns, or electronic ghosts, but something real. Kirtland Army Air Force Base, just north of the White Sands Proving Ground, tracked the flying craft into its near vicinity. The commanding officer there ordered a decorated World War II pilot named Kenny Chandler into a fighter jet to locate and chase the unidentified flying craft. This fact has never before been disclosed.
Chandler never visually spotted what he'd been sent to look for. But within hours of Chandler's sweep of the skies, one of the flying objects crashed near Roswell, New Mexico. Immediately, the office of the Joint Chiefs of Staff, or JCS, took command and control and recovered the airframe and some propulsion equipment, including the crashed craft's power plant, or energy source. The recovered craft looked nothing like a conventional aircraft. The vehicle had no tail and it had no wings. The fuselage was round, and there was a dome mounted on the top. In secret Army intelligence memos declassified in 1994, it would be referred to as a "flying disc". Most alarming was a fact kept secret until now, inside the disc, there was a very earthly hallmark: Russian writing. Block letters from the Cyrillic alphabet had been stamped, or embossed, in a ring running around the inside of the craft.
In a critical moment, the American military had its worst fears realized. The Russian army must have gotten its hands on German aerospace engineers more capable than Ernst Steinhoff and Wernher von Braun, engineers who must have developed this flying craft years before for the German air force, or Luftwaffe. The Russians simply could not have developed this kind of advanced technology on their own. Russia's stockpile of weapons and its body of scientists had been decimated during the war; the nation had lost more than twenty million people. Most Russian scientists still alive had spent the war in the Gulag. But the Russians, like the Americans, the British, and the French, had pillaged Hitler's best and brightest scientists as war booty, each country taking advantage of them to move forward in the new world. And now, in July of 1947, shockingly, the Soviet supreme leader had somehow managed not only to penetrate U.S. airspace near the Alaskan border, but to fly over several of the most sensitive military installations in the western United States. Stalin had done this with foreign technology that the U.S. Army Air Forces knew nothing about. It was an incursion so brazen, so antithetical to the perception of America's strong national security, which included the military's ability to defend itself against air attack, that upper-echelon Army Intelligence officers swept in and took control of the entire situation. The first thing they did was initiate the withdrawal of the original Roswell Army Air Field press release, the one that stated that a "flying disc" landed on a ranch near Roswell, and then they replaced it with the second press release, the one that said that a weather balloon had crashed, nothing more. The weather balloon story has remained the official cover story ever since.
Of all the historically significant political/military events of the 20th Century, none have had more official explanations than the so called "Roswell Incident". In fact, as of 2011, the United States government has issued four sanctioned explanations: 1) The crash of a flying saucer, 2) the remains of a weather balloon, 3) the remains of a "Project Mogul" balloon, 4) Crash test dummies. Logic alone would dictate that if the government lied about the last three explanations, why should the general public believe the first one?
The fears were legitimate: fears that the Russians had hover-and fly technology, that their flying craft could outfox U.S. radar, and that it could deliver to America a devastating blow. The single most worrisome question facing the Joint Chiefs of Staff at the time was: What if atomic energy propelled the Russian craft? Or worse, what if it dispersed radioactive particles, like a modern-day dirty bomb? In 1947, the United States believed it still had a monopoly on the atomic bomb as a deliverable weapon. But as early as June 1942, Hermann Göring, commander in chief of the Luftwaffe, had been overseeing the Third Reich's research council on nuclear physics as a weapon in its development of an airplane called the "Amerika Bomber", designed to drop a dirty bomb on New York City. Any number of those scientists could be working for the Russians. The Central Intelligence Group, the CIA's institutional predecessor, did not yet know that a spy at Los Alamos National Laboratory, a man named Klaus Fuchs, had stolen bomb blueprints and given them to Stalin. Or that Russia was two years away from testing its own atomic bomb. In the immediate aftermath of the crash, all the Joint Chiefs of Staff had to go on from the Central Intelligence Group was speculation about what atomic technology Russia might have.
For the military, the very fact that New Mexico's airspace had been violated was shocking. This region of the country was the single most sensitive weapons-related domain in all of America. The White Sands Missile Range was home to the nation's classified weapons-delivery systems. The nuclear laboratory up the road, the Los Alamos Laboratory, was where scientists had developed the atomic bomb and where they were now working on nuclear packages with a thousand times the yield. Outside Albuquerque, at a production facility called Sandia Base, assembly-line workers were forging Los Alamos nuclear packages into smaller and smaller bombs. Forty-five miles to the southwest, at the Roswell Army Air Field, the 509th Bomb Wing was the only wing of long-range bombers equipped to carry and drop nuclear bombs.
Things went from complicated to critical at the revelation that there was a second crash site. Paperclip scientists Wernher von Braun and Ernst Steinhoff, still under review over the Juarez rocket crash, were called on for their expertise. Several other Paperclip scientists specializing in aviation medicine were brought in. The evidence of whatever had crashed at and around Roswell, New Mexico, in the first week of July in 1947 was gathered together by a Joint Chiefs of Staff technical services unit and secreted away in a manner so clandestine, it followed security protocols established for transporting uranium in the early days of the Manhattan Project.
The first order of business was to determine where the technology had come from. The Joint Chiefs of Staff tasked an elite group working under the direct orders of G-2 Army intelligence to initiate a top secret project called "Operation Harass". Based on the testimony of America's Paperclip scientists, Army intelligence officers believed that the flying disc was the brainchild of two former Third Reich airplane engineers, named Walter and Reimar Horten, now working for the Russian military. Orders were drawn up. The manhunt was on.
Walter and Reimar Horten were two aerospace engineers whose importance in seminal aircraft projects had somehow been overlooked when America and the Soviet Union were fighting over scientists at the end of the war. The brothers were the inventors of several of Hitler's flying-wing aircraft, including one called the Horten 229 or Horten IX, a wing-shaped, tailless airplane that had been developed at a secret facility in Baden-Baden during the war. From the Paperclip scientists at Wright Field, the Army Intelligence investigators learned that Hitler was rumored to have been developing a faster-flying aircraft that had been designed by the brothers and was shaped like a saucer. Maybe, the Paperclips said, there had been a later-model Horten in the works before Germany surrendered, meaning that even if Stalin didn't have the Horten brothers themselves, he could very likely have gotten control of their blueprints and plans.
The flying disc that crashed at Roswell had technology more advanced than anything the U.S. Army Air Forces had ever seen. Its propulsion techniques were particularly confounding. What made the craft go so fast? How was it so stealthy and how did it trick radar? The disc had appeared on Army radar screens briefly and then suddenly disappeared. The incident at Roswell happened just weeks before the National Security Act, which meant there was no true Central Intelligence Agency to handle the investigation. Instead, hundreds of Counter Intelligence Corps [CIC] officers from the U.S. Army's European command were dispatched across Germany in search of anyone who knew anything about Walter and Reimar Horten. Officers tracked down and interviewed the brothers' relatives, colleagues, professors, and acquaintances with an urgency not seen since Operation ALSOS, in which Allied Forces sought information about Hitler's atomic scientists and nuclear programs during the war.
A records group of more than three hundred pages of Army Intelligence documents reveals many of the details of "Operation Harass". They were declassified in 1994, after a researcher named Timothy Cooper filed a request for documents under the Freedom of Information Act. One memo, called 'Air Intelligence Guide for Alleged Flying Saucer Type Aircraft', detailed for CIC officers the parameters of the flying saucer technology the military was looking for, features which were evidenced in the craft that crashed at Roswell.
Extreme maneuverability and apparent ability to almost hover; a plan form approximating that of an oval or disc with dome shape on the surface; the ability to quickly disappear by high speed or by complete disintegration; the ability to group together very quickly in a tight formation when more than one aircraft are together; evasive motion ability indicating possibility of being manually operated, or possibly, by electronic or remote control.
The Counter Intelligence Corps' official 1947 C1948 manhunt for the Horten brothers reads at times like a spy novel and at times like a wild goose chase. The first real lead in the hunt came from Dr. Adolf Smekal of Frankfurt, who provided CIC with a list of possible informants' names. Agents were told a dizzying array of alleged facts: Reimar was living in secret in East Prussia; Reimar was living in Göttingen, in what had been the British zone; Reimar had been kidnapped "presumably by the Russians" in the latter part of 1946. If you want to know where Reimar is, one informant said, you must first locate Hannah Reitsch, the famous aviatrix who was living in Bad Hauheim. As for Walter, he was working as a consultant for the French; he was last seen in Frankfurt trying to find work with a university there; he was in Dessau; actually, he was in Russia; he was in Luxembourg, or maybe it was France. One German scientist turned informant chided CIC agents. If they really wanted to know where the Horten brothers were, he said, and what they were capable of, then go ask the American Paperclip scientists living at Wright Field.
Neatly typed and intricately detailed summaries of hundreds of interviews with the Horten brothers' colleagues and relatives flooded the CIC. Army Intelligence officers spent months chasing leads, but most information led them back to square one. In the fall of 1947, prospects of locating the brothers seemed grim until November, when CIC agents caught a break. A former Messerschmitt test pilot named Fritz Wendel offered up some firsthand testimony that seemed real. The Horten brothers had indeed been working on a flying saucer-like craft in Heiligenbeil, East Prussia, right after the war, Wendel said. The airplane was ten meters long and shaped like a half-moon. It had no tail. The prototype was designed to be flown by one man lying down flat on his stomach. It reached a ceiling of twelve thousand feet. Wendel drew diagrams of this saucerlike aircraft, as did a second German informant named Professor George, who described a later model Horten as being "very much like a round cake with a large sector cut out" and that had been developed to carry more than one crew member. The later-model Horten could travel higher and faster, up to 1,200 mph. because it was propelled by rockets rather than jet engines. Its cabin was allegedly pressurized for high-altitude flights.
The Americans pressed Fritz Wendel for more. Could it hover? Not that Wendel knew. Did he know if groups could fly tightly together? Wendel said he had no idea. Were "high speed escapement methods" designed into the craft? Wendel wasn't sure. Could the flying disc be remotely controlled? Yes, Wendel said he knew of radio-control experiments being conducted by Siemens and Halske at their electrical factory in Berlin. Army officers asked Wendel if he had heard of any hovering or near-hovering technologies. No. Did Wendel have any idea about the tactical purposes for such an aircraft? Wendel said he had no idea.
The next batch of solid information came from a rocket engineer named Walter Ziegler. During the war, Ziegler had worked at the car manufacturer Bayerische Motoren Werke, or BMW, which served as a front for advanced rocket-science research. There, Ziegler had been on a team tasked with developing advanced fighter jets powered by rockets. Ziegler relayed a chilling tale that gave investigators an important clue. One night, about a year after the war, in September of 1946, four hundred men from his former rocket group at BMW had been invited by Russian military officers to a fancy dinner. The rocket scientists were wined and dined and, after a few hours, taken home. Most were drunk. Several hours later, all four hundred of the men were woken up in the middle of the night by their Russian hosts and told they were going to be taking a trip. Why Ziegler wasn't among them was not made clear. The Germans were told to bring their wives, their children, and whatever else they needed for a long trip. Mistresses and livestock were also fine. This was not a situation to which you could say no, Ziegler explained. The scientists and their families were transported by rail to a small town outside Moscow where they had remained ever since, forced to work on secret military projects in terrible conditions. According to Ziegler, it was at this top secret Russian facility, exact whereabouts unknown, that the German scientists were developing rockets and other advanced technologies under Russian supervision. These were Russia's version of the American Paperclip scientists. It was very possible, Ziegler said, that the Horten brothers had been working for the Russians at the secret facility there.
For nine long months, CIC agents typed up memo after memo relating various theories about where the Horten brothers were, what their flying saucers might have been designed for, and what leads should or should not be pursued. And then, six months into the investigation, on 12 March 1948, along came abrupt news. The Horten brothers had been found. In a memo to the European command of the 970th CIC, Major Earl S. Browning Jr. explained. "The Horten Brothers have been located and interrogated by American Agencies", Browning said. The Russians had likely found the blueprints of the flying wing after all. "It is Walter Horten's opinion that the blueprints of the Horten IX may have been found by Russian troops at the Gotha Railroad Car Factory", the memo read. But a second memo, entitled 'Extracts on Horten', Walter, explained a little more. Former Messerschmitt test pilot Fritz Wendel's information about the Horten brothers' wingless, tailless, saucerlike craft that had room for more than one crew member was confirmed. "Walter Horten's opinion is that sufficient German types of flying wings existed in the developing or designing stages when the Russians occupied Germany, and these types may have enabled the Russians to produce the flying saucer".
There is no mention of Reimar Horten, the second brother, in any of the hundreds of pages of documents released to Timothy Cooper as part of his Freedom of Information Act request, despite the fact that both brothers had been confirmed as located and interrogated. Nor is there any mention of what Reimar Horten did or did not say about the later-model Horten flying discs. But one memo mentioned "the Horten X"
Due to the rapidly deteriorating war conditions in Germany in the last months of WWII, the RLM [Reichs Luftfahrt Ministerium, or German Air Ministry] issued a specification for a fighter project that would use a minimum of strategic materials, be suitable for rapid mass production and have a performance equal to the best piston engined fighters of the time. The 'Volksjäger' [People's Fighter] project, as it became known, was issued on 8 September 1944 to Arado, Blohm & Voss, Fiesler, Focke-Wulf, Junkers, Heinkel, Messerschmitt and Siebel. The new fighter also needed to weigh no more than 2000 kg [4410 lbs], have a maximum speed of 750 km/h [457 mph], a minimum endurance of 30 minutes, a takeoff distance of 500 m [1604 ft], an endurance of at least 30 minutes and it was to use the BMW 003 turbojet.
Although not chosen to submit a design, the Horten Brothers came up with the Ho X  that met the specifications laid out by the RLM. Using a similar concept that they had been working on with their Horten IX [Ho 229] flying wing fighter, the Ho X was to be constructed of steel pipes covered with plywood panels in the center section, with the outer sections constructed from two-ply wood beams covered in plywood. The wing featured two sweepbacks, approximately 60 degrees at the nose, tapering into a 43 degree sweepback out to the wingtips. Control was to be provided by combined ailerons and elevators at the wingtips, along with drag surfaces at the wingtips for lateral control. A single BMW 003E jet engine with 900 kp of thrust was housed in the rear of the aircraft, which was fed by two air intakes on either side of the cockpit. One advantage to this design was that different jet engines could be accommodated, such as the Heinkel-Hirth He S 011 with 1300 kp of thrust, which was to be added later after its development was complete. The landing gear was to be of a tricycle arrangement and the pilot sat in a pressurized cockpit in front of the engine compartment. Armament consisted of a single MK 108 30mm cannon [or a single MK 213 30mm cannon] in the nose and two MG 131 13mm machine guns, one in each wing root.
In order to determine the center of gravity on various sweepback angles, scale models with a 3.05 meter [10 feet] wingspan were built. A full-sized glider was also under construction but was not completed before the war's end. Due to the ending of hostilities in 1945, the Horten Ho X was not completed.
Of the competing firms the Heinkel He 162 Volksjäger a single-engine, jet-powered fighter aircraft, designed and built quickly, and made primarily of wood as metals were in very short supply and prioritised for other aircraft, was the winner. The He 162 was the fastest of the first generation of Axis and Allied jets. Other names given to the plane include 'Salamander', which was the codename of its construction program, and 'Spatz' [Sparrow], which was the name given to the plane by Heinkel.
and another referred to "the Horten XIII" . No further details have been provided, and a 2011 Freedom of Information Act request by the author met a dead end.
The Horten Ho XIII B supersonic flying wing fighter was developed from the Ho XIII A glider, which had 60 degree swept-back wings and an underslung nacelle for the pilot. The XIII B was to be powered by a single BMW 003R turbojet/rocket engine. The cockpit was located in the base of a large, sharply swept vertical fin. Like the research XIII A glider, the XIII B also had swept back wings at a 60 degree angle. Projected armament were two MG 213 20mm cannon, and the Ho XIII B was projected to be flying by mid-1946.
On 12 May 1948, the headquarters of European command sent the director of Intelligence at the United States Forces in Austria a puzzling memo. "Walter Horten has admitted his contacts with the Russians", it said. That was the last mention of the Horten brothers in the Army Intelligence's declassified record for "Operation Harass".
Whatever else officially exists on the Horten brothers and their advanced flying saucer continues to be classified as of 2011, and the crash remains from Roswell quickly fell into the blackest regions of government. They would stay at Wright-Patterson Air Force Base for approximately four years. From there, they would quietly be shipped out west to become intertwined with a secret facility out in the middle of the Nevada desert. No one but a handful of people would have any idea they were there.
Lt Col Walker, at the Air Material Command, asked his operatives in the field to discretely track down the Horten brothers and ascertain whether their radical "Flying Wing" designs - developed during WWII - might be responsible for the rash of Flying Saucer sightings in 1947.
1. The Horten brothers, Reimar and Walter, are residing in Göttingen at present. However, both of them are traveling a great deal throughout the Bi-Zone. Walter at present is traveling in Bavaria in search of a suitable place of employment. It is believed that he may have contacted USAFE Head-quarters in Wiesbaden for possible evacuation to the United States under "Paper Clip". Reimer is presently studying advanced mathematics at the university of Bonn, and is about to obtain his doctor's degree. It is believed that when his studies are completed he intends to accept a teaching position at the Institute for Technology [Techniscbe Hochschule] in Braunschweig sometime in February or March 1948.
2. Both brothers are exceedingly peculiar and can be easily classified as eccentric and individualistic. Especially is this so of Reimar. He is the one who developed the theory of the flying wing and subsequently of all the models and aircrafts built by the brothers. Walter, on the other hand is the engineer who tried to put into practice the several somewhat fantastic ideas of his brother. The clash of personalities resulted in a continuous quarrel and friction between the two brothers. Reimar was always developing new ideas which would increase the speed of the aircraft or improve its manoeuvrability; Walter on the other hand was tearing down the fantastic ideas of his brother by practical calculations and considerations.
3. The two men worked together up to and including the "Horten VIII" a flying wing intended to be a fighter plane powered with two Hirt engines [HM-60-R] with a performance of approximately 650 horsepower each. After the "Horten VIII" was finished, one of the usual and frequent quarrels separated the two brothers temporarily. Walter went to work alone on the "Horten IX", which is a fighter plane of the flying wing design, with practically no changes from the model VIII except for the engines. Walter substituted the Hirt engines with BMW Jets of the type TL-004. The plane was made completely of plywood and was furnished with a Messerschmidt ME-109 Landing gear.
The model of this aircraft (Horten IX) was tested extensively in the supersonic wind tunnel [Mach No. 1.0] of the aero-dynamic testing institute [Aerodynamische Versuchsanstalt, located in Göttingen. The tests were conducted in the late summer of 1944 under the personal supervision of Professor Betz, chief of the institute. Betz at that time was approximately sixty years old and next to Prandtel [then seventy-eight years old], was considered to be the best man on aerodynamics in Germany. Betz's attitude toward the flying wing is very conservative to say the least. Basically he is against the design of any flying wing. According to the official reports about the tests, air disturbances were created on the wing tips, resulting in air vacuums, which in turn would prevent the steering mechanism from functioning properly. This seems logical as, of course, neither the ailerons nor the rudders could properly accomplish their function in a partial vacuum created by air disturbances and whirls.
In spite of that, two Horten IX's were built and tried out by a test pilot, Eugen [now living in Gottingen] at Rechlin in the fall of 1944. One of the two planes, piloted by another test pilot, developed trouble with one of the jet engines while the pilot was trying to ascertain the maximum rate of climb. The right jet stopped suddenly, causing the aircraft to go into an immediate spin and subsequent crash in which the pilot was killed. Eugen, however, was more fortunate in putting the other ship through all the necessary paces without the least trouble. He maintains that the maximum speed attained was around 950 km per hour, and that there were no steering difficulties whatsoever, and that the danger of both head and tail spins was no greater that any other conventional aircraft.
After extensive tests, the Horten IX was accepted by the German Air Force as represented by Göring, who ordered immediate mass production. The first order went to Gothaer Waggon Fabrik, located in Gotha [Thuringia] in January 1945. Göring requested that ten planes be built immediately and that the entire factory was to concentrate and be converted to the production of the Horten IX. The firm in question received all the plans and designs of the ship. In spite of this explicit order, production of the Horten IX was never started. The technical manager of the firm, Berthold, immediately upon receipt of the plans, submitted a number of suggestions to improve the aircraft. It is believed that his intention was to eliminate the Horten brothers as inventors and to modify the ship to such an extent that it would be more his brain child than anybody else's. Numerous letters were exchanged from High Command of the German Air Force and Dr. Berthold, which finally were interrupted by the armistice in May 1945. When US troops occupied the town of Gotha, the designs of the Horten IX were kept in hiding and not handed over to American Military authorities. The original designs in possession of the Horten brothers were hidden in a salt mine in Salzdettfurt, but the model tested by Eugen was destroyed in April 1945. The original designs were recovered from Salzdettfurt by British authorities in the summer of 1945.
The Horten brothers, together with Dr. Betz, Eugen and Dr. Stüper [the test pilot of the aerodynamic institute in Gottingen], were invited to go to England in the late summer of 1945 where they remained for approximately ninety days. They were interrogated and questioned about their ideas and were given several problems to work on. However Reimar was very unwilling to cooperate to any extent whatsoever, unless an immediate contract was offered to him and his brother. Walter, on the other hand, not being a theoretician, was unable to comply and Reimar was sufficiently stubborn not to move a finger. Upon their return to Göttingen Walter remained in contact with British authorities and was actually paid a salary by the British between October 1945 and April 1946, as the British contemplated but never did offer him employment. Walter subsequently had a final argument with his brother and the two decided to part. Reimar then went to the university of Bonn to obtain his degree, and Walter organized an engineering office in Göttingen which served as a cover firm to keep him out of trouble with the labor authorities. Walter married Fräulein von der Gröben, an extremely intelligent woman, former chief secretary to Air Force General Udet.
In the spring of 1947 Walter Horten heard about the flying wing design in the United States by Northrop and decided to write Northrop for employment. He was answered in the summer of 1947 by a letter in which Northrop pointed out that he, himself, could not do anything to get him over to the States, but that he would welcome it very much if he could come to the United States and take up employment with the firm. He recommended that Walter should get in touch with USAFE Headquarters in Wiesbaden in order to obtain necessary clearance.
4. As can be seen from the above, most of the Hortens' work took place in Western Germany. According to our source, neither of the brothers ever had any contact with any representative of the Soviet Air Force or any other foreign power. In spite of the fact that Reimar is rather disgusted with the British for not offering him a contract, it is believed very unlikely that he has approached the Soviet authorities in order to sell out to them. The only possible link between the Horten brothers and the Soviet authorities is the fact that a complete set of plans and designs were hidden at the Gothaer Waggon Fabrik and the knowledge of this is known by Dr. Berthold and a number of other engineers. It is possible and likely that either Berthold or any of the others having knowledge of the Horten IX would have sold out to the Soviet authorities for one of a number of reasons. However, this will be checked upon in the future, and it is hoped that contact with the the Gothaer Waggon Fabrik can be established.
All the above mentioned people contacted independently and at different times are very insistent on the fact that to their knowledge and belief no such design ever existed nor was projected by any of the German air research institutions. While they agree that such a design would be highly practical and desirable, they do not know anything about its possible realization now or in the past.
First, some excerpts from: "The Horten Flying Wing in World War II: The History & Development of the Ho 229", by H. P. Dabrowski, translated from the German by David Johnson [Schiffer Military History Vol. 47].
"In February 1945 Heinz Scheidhauer flew the Ho VII to Göttingen. Hydraulic failure prevented him from extending the aircraft's undercarriage, and he was forced to make a belly landing. The resulting damage had not been repaired when, on 7 April 1945, US troops occupied the airfield. The aircraft presumably suffered the same fate as the Ho V and was burned.
"The [Ho IX V1, RLM-Number 8-229] machine was sent to Brandis, where it was to be tested by the military and used for training purposes. It was found there by soldiers of the US 9th Armored Division at the end of the war and was later burned in a 'clearing action'.
"Construction of the Ho IX V3 was nearly complete when the Gotha Works at Friederichsroda were overrun by troops of the American 3rd Army's VII Corps on 14 April 1945. The aircraft was assigned the number T2-490 by the Americans. The aircraft's official RLM designation is uncertain, as it was referred to as the Ho 229 as well as the Go 229. Also found in the destroyed and abandoned works were several other prototypes in various stages of construction, including a two-seat version The V3 was sent to the United States by ship, along with other captured aircraft, and finally ended up in the H.H. "Hap" Arnold collection of the Air Force Technical Museum. The wing aircraft was to have been brought to flying status at Park Ridge, Illinois, but budget cuts in the late forties and early fifties brought these plans to an end. The V3 was handed over to the present-day National Air and Space Museum [NASM] in Washington D.C."
From these excerpts we see that certainly by late April or early May, 1945, the US had not just knowledge but at least semi-functional examples of the Horten flying wing. Ii can be assumed that the US would have wanted these craft back home for study as soon as was practical.
"It is possible within the present U.S. knowledge -provided extensive detailed development is undertaken- to construct a piloted aircraft which has the general description of the object in subparagraph (e) above which would be capable of an approximate range of 700 miles at subsonic speeds".
Why only possible? The Horten flying wing(s) had already been in US possession for two years.
"Any developments in this country along the lines indicated would be extremely expensive, time consuming and at the considerable expense of current projects and therefore, if directed, should be set up independently of existing projects".
Why expensive? The design, prototype and development work had already been completed. Is this a dodge for more money?
"Due consideration must be given the following: The possibility that these objects are of domestic origin - the product of some high security project not known to AC/AS-2 or this command".
How likely is it that the AMC was unaware of the captured Horten flying wing(s)?
"This opinion was arrived at in a conference between personnel from the Air Institute of Technology, Intelligence T-2, Office, Chief of Engineering Division, and the Aircraft, Power Plant and Propeller Laboratories of Engineering Division T-3".
How likely is it that these groups were unaware of the captured Horten flying wing(s)?
(1) The objects are domestic [U.S.] devices.
(2) Objects are foreign, and if so, it would seem most logical to consider that they are from a Soviet source.
"The Soviets possess information on a number of German flying-wing type aircraft, such as the Gotha P60A, Junkers EF-130 long-range jet bomber and the Horten 229 twin-jet fighter, which particularly resembles some of the descriptions of unidentified flying objects".
This report was prepared by the US Air Force's Directorate of Intelligence and the Office of Naval Intelligence and more than a year has passed since Twining's letter.
How is it that these agencies believe that it is the Soviets who have the captured Horten flying wing(s) or just information when, by this time, the US has had them for at least three years? What value would there be in pointing the finger at the Soviets and suggesting that they have aircraft far in advance of our own?
Klass contends that the USAF Directorate of Intelligence and the Office of Naval Intelligence demonstrate no knowledge of a Roswell-related crashed object/disk because there wasn't such an incident. Yet, three years after the fact, these same offices demonstrate no knowledge of the US possession of the Horten flying wing(s).
Klass can't have it both ways - and neither can the rest of us.
If these offices were not aware of the US possession of the Horten flying wing(s) then the so-called UFO cover-up exceeded their need-to-know and began before the Roswell incident.
If these offices were aware of the US possession of the Horten flying wing(s) then why would they not acknowledge such [in a Top Secret document that took 37 years to declassify]?
Reports of an alien spacecraft being struck by lightning and crashing late at night in early July 1947, near Roswell, New Mexico, were the beginnings of the most compelling event in all UFO lore.
Originally reported in the "Fort Worth Star-Telegram" and confirmed by military officials as authentic, the report was later refuted by the military and the crash remains were claimed to be nothing more than a weather balloon.
Horten Parabola in 1945, copied by the U.S. postwar?
A prototype of the Horten Ho 229 made a successful test flight just before Christmas 1944, but by then time was running out for the Nazis and they were never able to perfect the design or produce more than a handful of prototype planes.
However, an engineering team has reconstructed the bomber –albeit one that cannot fly– from blueprints.
It was designed with a greater range and speed than any plane previously built and was the first aircraft to use the stealth technology now deployed by the US in its B-2 bombers.
It has been recognised that Germany's technological expertise during the war was years ahead of the Allies, from the Panzer tanks through to the V-2 rocket.
But, by 1943, the Nazis were keen to develop new weapons as they felt the war was turning against them.
Nazi bombers were suffering badly when faced with the speed and manoeuvrability of the Spitfire.
In 1943 Luftwaffe chief Hermann Göring demanded that designers come up with a bomber that would meet his "1,000, 1,000, 1,000" requirements – one that could carry 1,000kg over 1,000km flying at 1,000km/h.
Two pilot brothers in their thirties, Reimar and Walter Horten, suggested a "flying wing" design which they were sure would meet Göring's specifications.
The centre pod was made from a welded steel tube, and was designed to be powered by a BMW 003 engine.
But the most significant innovation was Reimar Horten's idea to coat it in a mix of charcoal dust and wood glue which he believed would absorb the electromagnetic waves of radar.
They hoped that that, in conjunction with the aircraft's sculpted surfaces, would render it almost invisible to radar detectors.
This was the same method eventually used by the U.S. in its first stealth aircraft in the early 1980s, the F-117A 'Nighthawk'.
Until now, experts had always doubted claims that the Horten could actually function as a stealth aircraft.
But, using the blueprints and the only remaining prototype craft, Northrop-Grumman defence firm built a fullsize replica of a Horten Ho 229, which cost £154,000 and took 2,500 man-hours to construct.
The aircraft is not completely invisible to the type of radar used in the war, but it would have been stealthy enough and fast enough to reach London before Spitfires could be scrambled.
"If the Germans had had time to develop these aircraft, they could well have had an impact," Peter Murton, aviation expert from the Imperial War Museum at Duxford, in Cambridgeshire told the "Daily Mail".
"In theory the flying wing was a very efficient aircraft design which minimised drag.
"It is one of the reasons that it could reach very high speeds in dive and glide and had such an incredibly long range".
The research was filmed for a documentary on the "National Geographic Channel".
In the early 1960s, the prototype jet was transferred to a Smithsonian facility in Maryland that is off-limits to the public. It remains there today.
"There have been no documents released on it, and the public has no access to it," said Michael Jorgensen, a documentary filmmaker who secured National Geographic Channel backing to assemble a team of Northrop Grumman aeronautical engineers to study the craft and build a full-size replica from original plans. The completed model, which has a 55-foot wingspan, was quietly trucked to San Diego to join the San Diego Air & Space Museum's permanent collection.
The big mystery: Was this a stealth aircraft created more than three decades before modern stealth technology debuted? Could the wedge-shaped jet — almost completely formed of wood — actually evade radar detection? If so, military analysts wonder if the outcome of the war might have been different had the Germans had time to deploy the technology. The prototype craft was successfully tested by the Germans in late 1944.
The reconstruction process was filmed over three months last fall by Jorgensen's Flying Wing Films production company. Film crews followed the model to Northrop Grumman's restricted test site in the Mojave Desert in January, where the craft was mounted five stories high on a rotating pole. Radar was aimed at it from every direction and aerial attacks were simulated.
"It was a chance to be involved in solving a mystery that has baffled aviation historians for a long time," said Jim Hart, a spokesman for Northrop Grumman, which created the B-2 stealth bomber.