Walter Horten and Reimar Horten, sometimes credited as the Horten Brothers, were German aircraft pilots and enthusiasts, and members of the Hitler Youth and Nazi party. Though they had little, if any, formal training in aeronautics or a related field, the Hortens designed some of the most advanced aircraft of the 1940s, including the world's first jet-powered flying wing, the Horten Ho 229.
The Horten H.IX, designation Ho 229 (often called Gotha Go 229 due to the identity of the chosen manufacturer of the aircraft) was a late-World War II prototype fighter/bomber designed by Reimar and Walter Horten and built by Gothaer Waggonfabrik. It was the first pure flying wing powered by a jet engine and designed to be more difficult to detect with radar — the first aircraft to incorporate what is now known as stealth technology. It was a personal favorite of German Luftwaffe Reichsmarschall Hermann Göring, and was the only aircraft to come close to meeting his "3x1000" performance requirements, namely to carry 1000?kg of bombs a distance of 1000?km with a speed of 1000?km/h. Its speed was estimated at 1,024 km/h (636 mph) and its ceiling 15,000 meters (49,213 ft).
Wood in the construction of the IX proved a natural choice as it was relatively available, readily accessible and required very little training to work with. Considering the manufacturing restrictions imposed against the German war machine at this time, it made perfect sense. Wood could in many ways take on battlefield punishment better than metal, all the while keeping the flying surfaces generally in check despite. With a wing full of wood, this could potentially make the Ho 229 a beast to bring down with machine gun fire unless leveling a critical hit against a component such as the cockpit or one of the engines. it was suspected that the wing could receive a blast as great as a 20mm projectile and still keep its integrity.
The charcoal and sawdust mixture is of special note here for it essentially became the first true attempt to make an aircraft take on "stealth" like qualities intended to absorb incoming radar signals and deflate the outgoing signature. The mixture balance was purposely engineered to absorb the electromagnetic waves put out by British early warning ground-based radar systems defending the British mainland - the system responsible for the British victory over Germany in the Battle of Britain.
The powerplant was two Junkers Jumo 004 series jet engines. With the lack of vertical tail surfaces, the Ho IX made use of elevons with two spoilers differing in lengths located along the wings. The dual-spoiler configuration allowed for an improved control action to replace the action brought about by a more conventional rudder arrangement or single wing-mounted spoiler.
"Nurflügel", by Peter F. Selinger and Dr. Reimar Horten
Apparently it took 40 years to develop proper "fly by wire" technologies to make flying wings flyworthy. What came out of it is B2 Spirit, flying wing stealth bomber.