Horton Brothers Flying Wings

[RonRyan85]

What is the story on the WW2 Horten Brothers flying wings that
were first built as gliders in 1930? And were almost made with
jet engines toward the end of the war. Never finished as the
war ended too soon for Germany....what happened to make the
futuristic swept back wing designs so long in development? Did
the Germans distrust the Hortens?
Did the aircraft need jet engines that were more powerful? Lucky
for the Allies that Germany ran out of gasoline,pilots and
everything else as this design may have proved to be a great
"Wonder Weapon". Anyone have any comments?

[DerAdlerIstGelandet]

Actually the Ho-229 flew in January of 1945 and was preparing to enter production.

Comments:
First flown in January 1945, the Ho 229 was the innovative design of Walter and Reimar Horten, both former Luftwaffe officers. The test programme showed the 229 to have outstanding speed and handling characteristics but developement was halted when US troops overran the research facility.
http://www.warbirdsresourcegroup.org/LRG/ho229.html

[RonRyan85]

DerAdlerIstGelandet: Thanks for the info and for posting the
Ho229 pictures.

[Henk]

I have pictures for you and info but my PC is full of **** tonight and I can not get what I want. I will try to remmember next time.

Henk

[RonRyan85]

Henk: Thanks I'll be watching for the pictures.

[loomaluftwaffe]

Click here, i hope this helps

[Henk]

Here is a link that will be great info for you on the Horton brothers.

http://http://ufologie.net/aircraft/horten.htm

My pictures does not want to work but I am trying my best to get them posted and will get them to you as soon as I can.

Henk

[DerAdlerIstGelandet]

No problem

[Henk]

Horten 229 prototypes Part 1

Ok here they are. I have been promising these pics and now I will provide I can finally post them.

First is the Horten 229 V1 glider prototype, they first tested the design on this glider and it proved successfull. Sadly it were destroyed by the Russians after the war.













The cockpit of the Horten 229 V1.






Now the only Horten 229 to ever fly were the Horten 229 V2 prototype that were powered by two Jumo 004 jet engines. It was a successfull aircraft, but after a rough landing it were grounded until repairs have been made, but after the repairs were made the test pilot Erwin Ziller ignored the orders of the Horten brothers not to fly until they were there he did it anyway and that proved to be his last flight. The aircraft stalled and crashed killing him and destroying the only powered Horten 229 prototype. This meant that the Horten brothers had to wait even longer to be able to get things properly up and running. Here is the pics I have.

















Take off of the Horten 229 V2 powerd prototype.


Drawings of the Horten 229.












In Part two the Horten 229 V3 story and pictures of it then and now.

To be continued.....

Henk

[Henk]

Horten 229 prototypes Part 2

Ok, now on the first part I did the Horten 229 V1 and V2 prototypes. Now the V1 and V2 were destroyed, but the V3 did survived the war and it is now in the NASM waiting to be restored, but sadly never flew.

The story of the Horten 229 V3 is also sad in a certain way. It were captured and studied, but left to be forgotton in a hanger to rot for 61 years and not even to get the attention like other aircraft got.

Some pics of the Horten 229 V3 when it were captured and how it looks today.









The cockpit of the Horten 229 V3.








The Horten 229 V3 today.




The wings:














The inside of the aft landing gear bay.




The back of the aircraft.








The drag vlaps.


The front landing gear port you can see cockpit in the background.


The intake of the Jumo 004 engine.


The underside of the aircraft.


The V4.




The V5.


Next the full story of the Horten 229.

To be continued.....

Henk

[lesofprimus]

Excellent stuff Henk....

[Henk]

Horten 229 prototypes Part 3


Here is the story of the whole project. This is from the NASM website that also had interviews with the Horten brothers about their work, It is also on tape, their explanation for not restoring the Horten 229 V3 is that they are waiting for their new facility to be completed, this will all in all take 7 years.

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. (Note to the reader: 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 – 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 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 V b and V c 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 is 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.

To be continued.....

Henk

[Henk]

Thanks les.

Horten 229 prototypes Part 4

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.

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 stealthy 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.

Although the Garber Facility was closed to public tours in 2003, requests to view the extraordinary Horten Ho 229 V3 have continued to pour in to the Museum staff. Curators and restoration specialists hope to begin working on this artifact when the restoration shop complex is finished at the Steven F. Udvar-Hazy Center during the next several years.

Next the Horten 18 story.

To be continued.

Henk

[Henk]

I wrote to a magazine here in South Africa (WORLD AIRNEWS ) about the Horten 229 V3, but they made misstakes and just pissed me off so I told them, but ag ja they claimed that their info were correct. The response on that article were enormous and some even said that it should be brought to SA and restored here.

Here is a link to the magazine's website.

http://www.airnews.co.za/pages.php?page=default

Horten 18 America Bomber Part 5

This comes from Luft 46.

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 (8818 lbs). This bomber was to be able to fly from Germany to New York City and back without refueling. 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 the went about designing the XVIII A 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 exausted 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 Febuary 25, 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 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. Reimar was unhappy with the final design, so he went about redesigning the aircraft, to be known as the Ho XVIII B.

Henk

[Gnomey]

Great stuff Henk!