Question: The designers of the Horten H.XVIII also designed the world's first jet-powered flying wing known by what name?

full_context: Document 1: Horten H.IV: The Horten H.IV was a German tailless flying wing glider in which the pilot lay in a prone position to reduce the frontal area, and hence drag. It was designed by Reimar and Walter Horten in Göttingen. Four were built between 1941 and 1943. They were flown in a number of unofficial competitions in Germany during World War II. After the war the flying examples were transported to the United Kingdom and the United States where several contest successes were achieved.
Document 2: Junkers Ju 288: The Junkers Ju 288, originally known within the Junkers firm as the EF 074, was a German bomber project designed during World War II, which only ever flew in prototype form. The first of 22 development aircraft flew on 29 November 1940.
Document 3: Messerschmitt Me 262: The Messerschmitt Me 262, nicknamed Schwalbe (German: "Swallow") in fighter versions, or Sturmvogel (German: "Storm Bird") in fighter-bomber versions, was the world's first operational jet-powered fighter aircraft. Design work started before World War II began, but problems with engines, metallurgy and top-level interference kept the aircraft from operational status with the Luftwaffe until mid-1944. The Me 262 was faster and more heavily armed than any Allied fighter, including the British jet-powered Gloster Meteor. One of the most advanced aviation designs in operational use during World War II, the Me 262's roles included light bomber, reconnaissance and experimental night fighter versions.
Document 4: Horten brothers: Walter Horten (born 13 November 1913; died 9 December 1998 in Baden-Baden, Germany) and Reimar Horten (born 12 March 1915; died 14 March 1994 in Villa General Belgrano, Argentina), sometimes credited as the Horten Brothers, were German aircraft pilots and enthusiasts. Although they had little, if any, formal training in aeronautics or related fields, the Hortens designed some of the most revolutionary aircraft of the 1940s, including the world's first jet-powered flying wing, the Horten Ho 229.
Document 5: Heinkel He 277: The Heinkel He 277 was a four-engine, long-range heavy bomber design, originating as a derivative of the He 177, intended for production and use by the German Luftwaffe during World War II. The main difference was in engine configuration. Rather than using two fire-prone Daimler-Benz DB 606 "power system" engines, each of which consisted of side-by-side paired Daimler-Benz DB 601s and with each DB 606 "power system" weighing 1.5 tonnes apiece — or two of the similar DB 610, each of which used a pair of DB 605 engines in a similar "twinned" configuration on later He 177A airframes (the A-3 model and onwards), the He 277 was meant from the outset to use four BMW 801E 14-cylinder radial engines, each mounted in an individual nacelle and each turning a three-blade, four-meter diameter propeller. The design was never produced, and not a single prototype airframe was ever completed, owing both to the deteriorating condition of the German aviation industry late in the war, and the competition from other long-range bomber designs from other firms, competing for Germany's increasingly scarce aviation production capacity. Although not specifically intended for it at first, partially due to the time-frame in the spring of 1942 in which its ultimate niche was requested for by the RLM, the He 277 design essentially became Heinkel's entry in the important trans-oceanic range "Amerika Bomber" competition, struggling to compete against both several other designs from rival firms in the competition for a truly trans-oceanic ranged bomber for the Luftwaffe, and Germany's own rapidly degrading ability, from Allied bombing damage to its aviation plants, to produce military aircraft of any sort.
Document 6: Horten H.III: The Horten H.III was a flying wing sailplane built by Walter and Reimar Horten in Germany from 1937 to 1944.
Document 7: Heinkel He 162: The Heinkel He 162 "Volksjäger (German, "People's Fighter"), the name of a project of the Emergency Fighter Program design competition, was a German single-engine, jet-powered fighter aircraft fielded by the Luftwaffe in World War II. Designed and built quickly, and made primarily of wood as metals were in very short supply and prioritised for other aircraft, the He 162 was nevertheless the fastest of the first generation of Axis and Allied jets. "Volksjäger" was the Reich Air Ministry's official name for the government design program competition won by the He 162 design. 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.
Document 8: Silbervogel: Silbervogel, German for silver bird, was a design for a liquid-propellant rocket-powered sub-orbital bomber produced by Eugen Sänger and Irene Bredt in the late 1930s for The Third Reich/Nazi Germany. It is also known as the RaBo ("Raketenbomber" or "rocket bomber"). It was one of a number of designs considered for the "Amerika Bomber" mission, which started out in the spring of 1942 being focused solely on trans-Atlantic range piston-engined strategic bombers, like the Messerschmitt Me 264 and Junkers Ju 390, the only two airframe types actually built and flown for the competition. When Walter Dornberger attempted to create interest in military spaceplanes in the United States after World War II, he chose the more diplomatic term "antipodal bomber".
Document 9: Horten H.II: The Horten H.II Habicht (Hawk) was a German flying wing glider built in Germany in 1935. Four, including one flown mostly as a motorglider, were built. One of the gliders was used to test the aerodynamics of a prototype World War II Horten jet fighter-bomber.
Document 10: Junkers Ju 88: The Junkers Ju 88 was a German World War II "Luftwaffe" twin-engined multirole combat aircraft. Junkers Flugzeug- und Motorenwerke (JFM) designed the plane in the mid-1930s as a so-called "Schnellbomber" (fast bomber) that would be too fast for fighters of its era to intercept. It suffered from a number of technical problems during its development and early operational periods but became one of the most versatile combat aircraft of the war. Like a number of other "Luftwaffe" bombers, it served as a bomber, dive bomber, night fighter, torpedo bomber, reconnaissance aircraft, heavy fighter and at the end of the war, as a flying bomb.
Document 11: Horten H.VI: The Horten H.VI was a flying wing aircraft designed by the Horten brothers during World War II.
Document 12: Horten H.XVIII: The Horten H.XVIII was a proposed German World War II intercontinental bomber, designed by the Horten brothers with pioneering features such as a flying wing configuration, turbojet engines and stealth characteristics. The unbuilt H.XVIII represented, in many respects, a scaled-up version of the Horten Ho 229, a prototype jet fighter. The H.XVIII was one of many proposed designs for an "Amerika Bomber", and would have carried sufficient fuel for transatlantic flights.
Document 13: Horten Ho 229: The Horten H.IX, RLM designation Ho 229 (or Gotha Go 229 for extensive re-design work done by Gotha to prepare the aircraft for mass production) was a German prototype fighter/bomber initially designed by Reimar and Walter Horten to be built by Gothaer Waggonfabrik late in World War II. It was the first flying wing to be powered by jet engines.
Document 14: Heinkel: Heinkel Flugzeugwerke (] ) was a German aircraft manufacturing company founded by and named after Ernst Heinkel. It is noted for producing bomber aircraft for the Luftwaffe in World War II and for important contributions to high-speed flight, with the pioneering examples of a successful liquid-fueled rocket and a turbojet-powered aircraft in aviation history, with both Heinkel designs' first flights occurring shortly before the outbreak of World War II in Europe.
Document 15: Wright brothers: The Wright brothers, Orville (August 19, 1871 – January 30, 1948) and Wilbur (April 16, 1867 – May 30, 1912), were two American brothers, inventors, and aviation pioneers who are generally credited with inventing, building, and flying the world's first successful airplane. They made the first controlled, sustained flight of a powered, heavier-than-air aircraft on December 17, 1903, four miles south of Kitty Hawk, North Carolina. In 1904–05 the brothers developed their flying machine into the first practical fixed-wing aircraft. Although not the first to build and fly experimental aircraft, the Wright brothers were the first to invent aircraft controls that made fixed-wing powered flight possible.
ground_truth: Horten Ho 229