Northrop N-55: the tailless patroller from Hawthorne

In late 1948, the US Air Force concluded that its ability to defend the continental US from airstrikes was inadequate. Thus, it promulgated an across-the-board scheme to improve American air defense systems, which partly led to the WS-201 (aka 1954 Interceptor) requirement that resulted in development of the delta-winged Convair F-102 Delta Dagger and F-106 Delta Dart as well as the trisonic Republic XF-103 Thunderwarrior. After becoming aware of this situation, the Northrop company proposed an all-wing patrol plane under the designation N-55. The wingspan of the N-55 would be same as that the B-35 and B-49, but the fuselage design would mirror that of the N-31 flying wing bomber project in utilizing fore and aft crew nacelle extensions, giving the plane a length of 61.8 feet (18.8 meters). The N-55 concept was basically not just intended for long-range patrol missions but also would serve to function as an airborne radar picket ship that could fire air-to-air missiles against enemy planes that intruded into North American airspace. Search radars operating in the X-band or S-band ranges would be internally accommodated in the nose and tail of the N-55. 

Northrop N-55 sans suffixe (left) and N-55A (right) design studies for a long-range patrol flying wing

Two N-55 variants were studied. The baseline N-55 design was powered by two Northrop XT37-NA-3 turboprops each delivering 10,000 hp, and it was armed with 44 AAM-N-2 (later GAR-1/2/3/4/5/6/9 and finally AIM-4) Falcon air-to-air missiles (of which a dozen would be fired from leading edge tubes with eyelid covers, the rest being housed in two weapons bays). The N-55A had the same wingspan but was powered by six Westinghouse J40 turbojets. The turboprop-powered N-55 looked like a cross between the baseline N-31 and later N-31A versions because it had two T37 turboprop engines and a pair of vertical stabilizers, while the engine arrangement of the N-55A resembled that of the YB-49, with the jet engines buried between two pairs of vertical stabilizers on the wing's trailing edge.

References:

Chong, T., 2016. Flying Wings & Radical Things: Northrop's Secret Aerospace Projects & Concepts 1939-1994. Forest Lake, MN: Specialty Press.