The Horten H.XVIII was a proposed German World War II intercontinental bomber, designed by the Horten brothers. 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 the Langstreckenbomber, and would have carried sufficient fuel for transatlantic flights.
The B2 model of the H.XVIII was based on the airframe of the H.XVIIIA with a huge tail. It had an MG 151 turret set in the middle rear of the wing and with six BMW 003 turbojets slung under the wings; this was designed by Messerschmitt and Junkers engineers. It is uncertain if this overall design was directly developed by the Horten brothers or their manufacturer, as there is little surviving evidence of this proposed version. It was eventually rejected by the Horten brothers, as it was not a major improvement over the Ho XVIIIA.
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