Before the end of 1944, the German Air Ministry put forth a new proposal centered on a high-performance, high-altitude aircraft capable of meeting Allied bombers on their own terms. The Allied day and night bombing campaigns had wreaked havoc on German infrastructure and war-making capabilities that an interception solution was desperately needed - particularly if the highly-advanced Boeing B-29 "Superfortress" strategic heavy bomber was to eventually make its way to Europe. This led to several of the German concerns attempting to remedy the situation and stave off the nation's total capitulation.
For the Heinkel concern, best known for its He 111 medium bomber, engineers revisited the company's high-speed "He 100" fighter design (detailed elsewhere on this site) which was proposed against an earlier (mid-1930s) Luftwaffe requirement eventually filled by the excellent Messerschmitt Bf 109. Back in March of 1939, the same He 100 managed a then-record air speed of 463.9 miles-per-hour. The new Air Ministry requirement seemed to be in line with what a more advanced version of the He 100 could offer so company engineers went to work on a revised design.
The resulting fighter was given a very streamlined fuselage from nose-to-tail. At the nose was housed the supercharged inline piston engine - of which three different installs were eventually considered. An air scoop for the system was offset to the port side of the forward fuselage. The engine would drive a pair of three-bladed propeller units in tractor arrangement. The cockpit, with its teardrop style canopy offering excellent vision, was positioned over midships and the tail was of conventional triple-plane arrangement. Ground-running was accomplished through a narrow-track, "tail-dragger" undercarriage configuration, the main legs retracting away from centerline and under the wings (as in the Bf 109). The mainplane members were of particular note: slightly swept forwards (8-degrees) with greater sweep at the trailing edge. The wing tips were slightly rounded.
Proposed armament centered on a single 30mm MK 103 automatic cannon buried in the engine mounting, firing through the propeller hub (again, as in the Bf 109). In addition to this, the fighter would have been equipped with 2 x 30mm MK 108 automatic cannons at the wings (one gun to a wing). Total firepower from a single burst would have been enough to down the bombers being fielded by the British and the Americans.
Ultimately, the three powerplants in play became the Daimler Benz DB603M twin supercharged engine rated up to 2,100 horsepower (with injection) and the similarly rated Junkers Jumo 213E with its two-stage, three-speed supercharger. The final entry was the Daimler Benz DB603N with two-stage, twin supercharger with advanced cooling, this rated up to 2,750 horsepower at take-off.
As penciled out, the aircraft - known as "P.1076" - was given a running length of 31.5 feet, a wingspan of 36 feet, and a height of 9.5 feet. Weights (depending on engine fit) ranged from 7,100lb empty to 11,530lb fully loaded.
Estimated performance specifications included a maximum speed of 545 miles-per-hour with a range out to 830 miles and service ceiling of 47,500 feet (the latter quality requiring cockpit pressurization). All told, this would have made the P.1076 one of the fastest prop-driven fighters in the whole of the war.
At any event, the P.1076 never materialized into a physical, flyable specimen. The requirement was partially fulfilled by the advanced form of the Focke-Wulf Fw 190, the "Ta 152" (of which only 69 were produced before war's end). Detailed drawings of the P.1076 are said to have been completed for the United States by Siegfried Gunter (1899-1969), representing one-half of the talented and pioneering Gunter Brothers aeronautics team and the father of "Thrust Modulation Theory".