Vickers Type C 6Engine Super bomber
This project dates back to 1943 and is part of an RAF brief for a 'super bomber' with long range, adequate defensive armament and large bomb-load. The Type 'C' as the name suggests is one of several developments by Vickers in response to this brief (there were many other design from other leading aircraft manufacturers). However, it soon became apparent that at least five years would be needed to fully develop aircraft of this complexity and versatility. Coupled with the success of the Avro Lancaster and advent of practical jet propulsion made this (and the other proposals) redundant.
Span: 64.0m (210' 0") Length: 29.0m (95' 0") Max. Speed: 621 km/h (382 mph)

XB-46
This project dates from 1944. The USAAF and war department urgently called for bids to be made for a jet-bomber capable of competing with Luftwaffe jet fighters which were coming into service. The XB-46 was tendered along with the North American XB-45 (the Boeing XB-47 and Martin XB-48 were also included but extra development time put them back two years).
Although the war ended, the haste to find a jet-bomber did not stop as the threat from Soviet forces kept the momentum. However, even before proper trials began the XB-46 had already lost out on paper to the more conventional (and less risky) design of the XB-45 partly due to the newly formed USAF's concerns over the slenderness of the airframe (and consequent lack of equipment carrying potential) and greater weight.
One experimental aircraft was allowed to be completed which first flew in April 1947 and survived until 1952 as a USAF test-bed.
Span: 34.44m (113' 0") Length: 32.23m (105' 9") Max. Speed: 877 km/h (545 mph)

Northrop N-31A
Convinced that the flying wing format would eventually lead to a successful design Northrop built on lessons learned from early WW2 schemes and the B-35 and B-49 projects. This 1950 design included a more versatile body-shape that could accommodate a greater range of contemporary weapons, a more reliable power plant and had (on paper at least) excellent manoeuvrability, range and performance.
Several configurations were put forward, including two-engine variants utilising the Northrop Turbodyne V turboprop driving 2 3-bladed contra-prop, a four-engine variant with the Allison XT40 power unit and also a 6-engined pure jet. Defensive armament was to be a ‘Stinger' tail-mounted remote controlled gun turret.
The Boeing B-47 (and later B-52) successfully took on the long-range strategic bomber, the projected role for this aircraft.
Span 128’ 4” (39.12m) Length: 74’ 8” (22.76m) Projected Cruising Speed (2 x Turbodyne V) 450 Knots

Grumman G-71
This design for a fast carrier-based jet fighter was put forward by Grumman in November 1944. This small cantilever-winged fighter was to be armed with either 4 20mm cannon or 6 0.5 in machine guns across the nose. The wings were not of the folding type. The aircraft was to be powered by a single Westinghouse 24C jet engine delivering 3000lb of thrust. It is not clear why this promising project was cancelled.
Source: American Secret Projects - Fighters and Interceptors 1945-1978, Tony Buttler
Span: 9.9m (32' 6") Length: 10.0m (32' 11") Max. Speed: 861 km/h (535 mph)

Hawker P.1104
This proposed design for a Mach 2 all-weather fighter project of 1954 was one of Hawker's responses (along with its cousin the single engined P1103 of the same year) to the RAF's 'New Fighter' requirement F155T calling for an advanced high speed, high altitude interceptor.All the aircraft proposals, including those from other companies such as Armstrong Whitworth, Fairey and Vickers never made it to the prototype stage as in 1957 the Ministry of Defence controversially stopped further manned fighter development.
The power for the P1104 was to be supplied by two wing mounted superheated Gyron Junior engines; armament may have included new missile designs such as the Red Hebe and Red Dean.
Span: 13.4m (44' 0") Length: 21.8m (71' 5") Max. Speed: Mach 2+

Fairey GOR 339
General Operations Requirement 339 of 1957 called for a new tactical strike and reconnaissance aircraft as a supersonic replacement for the English Electric Canberra. The Fairey Aircraft Company, using data from the Delta projects submitted this canard design in early 1958. With two Rolls Royce RB142R or Olympus 15R engines as power-plants the design had proposed armament of 6 x 1000lb bombs, Red Beard rockets or rocket packs. The aircraft was never developed: the BAC TSR 2 being the eventual 'winner' of the requirement*.
Span: 10.6m (34' 8") Length: 30.7m (100' 9") Max. Speed: Mach 2.15 at 36,000ft

Hawker P.1048
Dating from early 1946, this design by Hawker was for a twin-jet high speed interceptor. To be powered by either 2 Rolls Royce AJ65s (the original designation of the Avon) or AS65s. The aircraft was to be armed with 2 x 30mm nose-mounted Aden cannon
The design is clearly informed by captured Axis jet aircraft. Post-dating the similar looking Gloster Meteor by several years the design would have been obsolete by the time any prototype was ready: it never left the drawing board.
Span: 12.0m (39' 5") Length: 12.5m (41' 0") Max. Speed: Unknown

好多都没听过，感谢楼主科普