[4] The Ho 229 was the only design that came close to the requirements, and the Horten brothers quickly received an order for three prototypes after the project gained Göring's approval.

Due to the Horten brothers' lack of suitable production facilities, Ho 229 manufacturing was contracted out to Gothaer Waggonfabrik; however, the company allegedly undermined the project by seeking the favour of Luftwaffe officials for its own flying wing design.

[citation needed] On 1 March 1944 the first prototype H.IX V1, an unpowered glider, made its maiden flight, followed by the H.IX V2, powered by Junkers Jumo 004 turbojet engines in December 1944.

At that time the German government was actively funding glider clubs as a response to the production of aircraft suitable for military roles being forbidden by the Treaty of Versailles.

[5] At the time, no conventional means for aircraft designers to meet these goals seemed viable because while the new Junkers Jumo 004B turbojets provided the speed, excessive fuel consumption limited range.

The lack of a vertical stabilizer meant that flying without any active yaw control would lead to an uncontrolled sideslip, and potentially flat spins.

[9] This arrangement was complicated by Gothaer's alleged efforts to persuade the authorities to favour its own projects, which included flying wings, over the Ho 229.

[10] Observing the Ho 229's design and development difficulties, Russell Lee, the chair of the Aeronautics Department at the National Air and Space Museum, speculated that an important motivation for the Horten brothers was to prevent them and their workers from being assigned dangerous roles by the German military.

[13] The H.IX was of mixed construction with the center section built up from welded steel tubing with a diameter up to 160 mm (6.3 in),[14] while the outer box wing spars were of pine.

[15] The outer wings were skinned with thin plywood panels that were glued together with a sawdust mixture and covered with fireproof paint.

Following the transference of design responsibility from the Horten brothers to Gothaer Waggonfabrik, the company's design team implemented several changes, including adding a simple ejection seat, substantially redesigned the undercarriage to enable a higher gross weight, changes to the engine intakes, and they added ducting to air-cool the jet engine's outer casing to prevent damage to adjacent wood.

[5] The Horten brothers were unable to witness this flight as they were occupied with producing the design for a new turbojet-powered strategic bomber in response to the Amerikabomber competition.

On 12 March 1945, nearly a week after the U.S. Army had launched Operation Lumberjack to cross the Rhine River, the Ho 229 was included in the Jäger-Notprogramm (Emergency Fighter Program) for the accelerated production of inexpensive "wonder weapons".

The V3 was larger than previous prototypes, the shape being modified in various areas,[citation needed] and it was meant to be a template for the pre-production series Ho 229 A-0 day fighters, of which 20 had been ordered.

[19] It is uncertain if the aircraft's original Junkers engines were ever run, although the American evaluation team at one point intended to fly it.

[24] In 1983, after hearing details of the US stealth system, Reimar Horten advanced a claim that he had intended to add charcoal dust to the wood glue to absorb electromagnetic waves (radar), to shield the aircraft from the British early-warning ground-based radar system known as Chain Home.

The team observed that the "Ho 229 leading edge has the same characteristics as the plywood [of the control sample] except that the frequencies have a slightly shorter bandwidth," which they go on to conclude was likely due to oxidization of the wood.

"[27][28] The Smithsonian Institution then performed a study of the materials used on the prototype, and determined that there is "no evidence of carbon black or charcoal", refuting the hypothesis.

[26] A jet-powered flying wing such as the Horten Ho 229 might have a smaller radar cross-section (RCS) than conventional contemporary twin-engine aircraft because the wings are blended into the fuselage and there are no large propeller disks or vertical and horizontal tail surfaces to provide a typical identifiable radar signature,[28][17] however the front and rear faces of the exposed jet engines do provide a similar degree of reflectivity to propellers.

[28] Northrop Grumman built a full-size non-flying reproduction of the V3, primarily made of wood, unlike the original aircraft, which had an extensive steel space-frame to which the wooden skin was bolted.