TYPE: Interceptor, fighter. Project.

ACCOMMODATION: Pilot only

POWER PLANT: One Kronach-Lorin coal burning ramjet, power output unknown

PERFORMANCE: 650 mph (estimated)

COMMENT: The Lippisch Li P.13b was a follow-on design from the Lippisch Li P.13a, and was also a ramjet fighter. Designed in December 1944, it featured Lippisch’s favorite wing plan, a delta design (sweepback was 60 degrees) with downturned wingtips. A double fin and rudder was chosen to provide steady flight, and the cockpit was moved forward for better pilot’s visibility, ahead of the delta wing’s apex. On each side of the cockpit on the wing’s leading edge were the air intakes which fed the ramjet. For take-off a liquid-fuel rocket driven trolley was used; additional rockets were necessary to accelerate the aircraft to speed for operating of ramjets. The main landing gear was a retractable landing skid, and the rear rested on the reinforced downturned wingtips. No armament was planned at this stage. Because of the fuel shortage in Germany at this stage in the war, an ingenious plan to use coal (or paraffin coated lignite dust) for fuel was to be tried. A centrally installed round or hexagonal heat-resistant ceramic combustion chamber was fitted in the interior of the wing, and was fillable from above. No tests were ever carried out with this design or with the unique power source and the project only stayed in stage of concept sketches on the drawing board (Ref.: 16).

TYPE: Interceptor fighter, experimental aircraft

ACCOMMODATION: Pilot only

POWER PLANT: One Heinkel/Hirth HeS 011 turbojet engine, rated at 1.300 kp

PERFORMANCE: 530 mph

COMMENT: End of 1943, the Arado Aircraft Company began work on a series of delta shaped, turbojet powered bombers, to fulfill the request of a “Long Range/High Speed Flying Wing Aircraft”.  In fact, most of the (in total 14) projects, designated Ar E.555-1 to -14, had a flying wing configuration because it  was thought to be the best design to fulfill a requirement of high speed, heavy loading and long-range aviation. Power was delivered by four to six turbojet engines. Due to the design acceptance by the RLM in early 1944, the Arado design team scaled down the projected, six turbojet engines equipped Arado E.555-1 bomber in same layout to design a smaller size fighter version, the Ar E.581-4. It was a single-seat fighter with a deep fuselage, and was powered by the single HeS 011 turbojet engine fed by a divided air intake under the cockpit. The wing was of a delta shape with the twin fins and rudders on the trailing edge, and the landing gear was of tricycle arrangement. Although work on the project was in progress Arado was ordered to cease all work on the  Ar E.581 for concentrating all facility resources on the existing fighter production (Jäger-Notprogramm, Fighter emergency program)  (Ref.: 16).

TYPE: Target defense interceptor. Project.

ACCOMMODATION: Pilot only, in seated position

POWER PLANT: Three Pabst/Lorin ramjets at wingtips, rated at 840 kp thrust each. For starting ramjets Walther 109-500 solid-fuel rockets were fitted to each ramjet, rated at 500 kp for 30 seconds each

PERFORMANCE: 621 mph (estimated)

COMMENT:  This Focke-Wulf Vertical Take-Off and Landing (VTOL) fighter/interceptor project was designed in September 1944, at the same time when the Heinkel Company worked on its VTOL-projects “Lerche” and “Wespe”. But in contrast to the latter two designs the propulsion system of the Focke-Wulf project was radical different. Three untapered wings rotated around the fuselage and had a gradually decreasing pitch towards the wingtips, thus acting like a giant propeller (“Triebflügel”). At the end of each wing was a Pabst ramjet. Since ramjets do not operate at slow speeds, the wing-rotor had to be driven by small Walter rocket engines, fitted to each ramjet pod. When the plane was sitting on its tail in the vertical position, the rotors would have functioned similarly to a helicopter. When flying horizontally, they would function more like a giant propeller. A cruciform empennage at the rear of the fuselage comprised four tail planes, fitted with moving ailerons that would also have functioned as combined rudders and elevators. A single large and sprung wheel in the extreme end of the fuselage provided the main undercarriage. Four small castoring wheels on extensible struts were placed at the end of each tail plane to steady the aircraft on the ground and allow it to be moved. The main and outrigger wheels were covered by streamlined clamshell doors when in flight. When taking off, the rotors would be angled to give lift as with a helicopter or, more accurately, a gyrodyne. Once the aircraft had attained sufficient altitude it could be angled into level flight. This required a slight nose-up pitch to provide some downward thrust as well as primarily forward thrust. Consequently, the four cannons in the forward fuselage would have been angled slightly downward in relation to the center line of the fuselage. The rotors provided the only significant lift in horizontal flight. To land, the aircraft had to slow its speed and pitch the fuselage until the craft was vertical. Power could then be reduced and it would descend until the landing gear rested on the ground. This would have been a tricky and probably dangerous maneuver given that the pilot would be seated facing upward and the ground would be behind his head at this stage. Unlike some other tail sitter aircraft, the pilot’s seat was fixed in the direction for forward flight. The spinning rotor would also obscure rear vision. Although the “Triebflügeljäger” project was not realized, a wind tunnel model was tested up to a speed of Mach 0.9 (Ref.: 17, 18, 23)

TYPE: Target defense interceptor. Project.

ACCOMMODATION: Pilot only, in prone position

POWER PLANT: Two Daimler-Benz DB 603E inline engines, rated at 2.400 hp each, driving contra-rotating propellers

PERFORMANCE: 497 mph

COMMENT: This Heinkel Vertical Take Off and Landing (VTOL) fighter/interceptor project was based on an earlier design, the Heinkel “Wespe” (Wasp). Work on the design started at the Heinkel Company in Vienna on February 25, 1945 and was completed on March 8, 1945. The “Lerche” (Lark) employed a ducted wing planform with contra-rotating propellers, powered by two Daimler-Benz DB 605E engines. This arrangement increased the effectiveness of the airscrews dramatically. During flight the pilot lied in a prone position in the extreme nose, while standing upright during take-off and landing. Projected armament was two MK 108 30mm cannon. The end of the war brought any realization to a termination. After the war this idea of a tail sitter was developed further by the US Navy, e. g. Convair XFY-1 Pogo and Lockheed XFV-1 Salmon (Ref.: 16).

TYPE: Fighter, interceptor. Project.

ACCOMMODATION: Pilot only

POWER PLANT: Heinkel-Hirth HeS 011, rated at 1,300 kp

PERFORMANCE: 612 mph at 22,970 ft

COMMENT: However, there is some evidence that a further production version of the Me P.1101 was on Messerschmitt’s drawing boards. All over dimensions, turbojet engines, tricycle undercarriage etc. are unchanged to its predecessor, the wing was swept back to 40 degree and a normal or horizontal tail unit – “T-Tail” was provided. Cockpit armor was fitted and up to four Kramer X-4 air-to-air guided missiles could be carried.

RUHRSTAHL/KRAMER X-4

The Kramer X-4 was the first air-to-air guided missile that entered the production lines. It featured a tapering, cigar-shaped fuselage, with four small swept wings and four smaller tail fins. At the ends of two of the opposing wings were small pods which held the wires that unwound during the X-4’s flight. On the wing tips of the other two main wings were simple flares to aid the pilot in keeping the X-4 on the intended path. The tail unit contained small spoilers which could control the missiles pitch and yaw. Power was supplied by the BMW 109-548 liquid-fuel rocket engine with 1,600 kp thrust for 33 seconds. A warhead weighing 20 with a destructive blast radius of 25 feet was mounted in the nose of the missile, being detonated by the pilot, impact or by an acoustical proximity fuse, tuned to the pitch of the bomber’s propellers. First air launched test took place on August, 1944 by a Focke-Wulf  Fw 190. Tests continued through early February 1945, also by Junkers Ju 88s as well as by a Messerschmitt  Me 262 jet fighter with two X-4 missiles under the wings outboard of the jet nacelle, but were not launched  (Ref.: 16).

TYPE: Fighter, interceptor. Project

ACCOMMODATION: Pilot only

POWER PLANT: One Heinkel-Hirth HeS 011 turbojet engine, rated at 1,300 kp

PERFORMANCE: 550 mph at 23,000 ft

COMMENT: Although the Messerschmitt Me P.1101 was from the onset designed as an experimental aircraft different production versions were planned, too. One design was very similar to the Me P.1101 V1 as far as all over dimensions, turbojet engines, tricycle undercarriage etc. are concerned, but the wing was in a fixed position at 40 degree and a horizontal tail unit – “T-Tail” was provided. The unconditional surrender of Germany brought all further work on this exceptional aircraft to an end (Ref.: 16).

TYPE: Fighter, interceptor. Project

ACCOMMODATION: Pilot only

POWER PLANT: Two Lorin ramjets, rated at 900 kp each

PERFORMANCE: No data available

COMMENT: The P.1079/13 was one of several Messerschmitt designs to meet the Luftwaffe’s late-War request for a small, cheap, single-seat target-defense interceptor. This design included two wing-mounted Lorin ramjets or conventional turbojet engines. For take-off a trolley-launch system was provided and solid fuel rockets were used for acceleration until the ramjets will work. After mission the aircraft landed on a skid. No further details are known.