In recent years, software modelling has suggested that the stealth and speed of the Hortens' flying wing jet designs would have made interception, prior to bombing, difficult and unlikely.
[2] The ability of bomber crews, in an aircraft such as the Horten H.XVIII, to attack targets in North America, might have been hampered by existing and emerging Allied air defence strategies and technologies, such as: The A model of the H.XVIII was a long, smooth blended wing body.
The aircraft was first proposed for the Langstreckenbomber competition initiated in late 1944 and was personally reviewed by Hermann Göring: after review, the Horten brothers (with deep dissatisfaction) were forced to share design and construction of the aircraft with Junkers and Messerschmitt engineers, who wanted to add a single rudder fin as well as suggesting underwing pods to house the engines and landing gear.
The aircraft was to be built in huge concrete hangars and operate off long runways with construction due to start in autumn 1945, but the end of the war came with no progress made.
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.