POWER PLANT: One Walter HWK 509C liquid-fuel rocket engine, rated at 2,400 kp thrust (main chamber: 2,000 kp thrust, auxiliary chamber 400 kp thrust)
PERFORMANCE: 569 mph (estimated)
COMMENT: In 1944 the Arado design team proposed two liquid-rocket engines powered reconnaissance versions of the Arado Ar 234 “Blitz” (Lightning) high-speed bomber. The Arado Ar 234R, as it was designated, would consist of a regular Ar 234C frame but without turbojet engines. Instead two pods were installed under the wing, each containing a Walter HWK 109-509A bi-fuel rocket engine (project Ar 234R-1A). The second project Ar 234R-1B was to be powered by a Walter HWK 109-509C two chamber liquid-fuel rocket engine mounted in the rear section. Therefore a cowling would have been installed in the rear fuselage underneath the rudder. The upper rocket engine called “Steigofen” (Accelerate chamber) delivered 2,000 kp and was to be used for climbing to altitude while the lower rocket engine, “Marschofen” (Cruising chamber) delivered 400 kp thrust and was used to power the aircraft during horizontal flight. During return flight – over a distance of more than 155 miles – the aircraft flew as a glider without power. The wing had a laminar profile with its maximal thickness at 50 to 60% chord. The glide ratio was calculated to 1:14.
Because of the limited fuel capacity and short endurance of the rocket engines the Ar 234R-1b was to be towed by a Heinkel He 177 “Greif” heavy bomber. A possible reconnaissance mission in the London area was calculated as follows: After take-off from a Luftwaffe base near Paris the aircraft was towed to the operational altitude of app. 26,247 ft, reached near Calais. After release of towline with “Steigofen” at full throttle the aircraft was powered at a speed of app. 506 mph to an altitude of app. 55,775 ft. This height was reached in a few minutes app. near the coast of Dover. During horizontal flight intermittent ignition of the “Marschofen” accelerated the aircraft with 569 mph to the target (i. e. London). After photo mission the aircraft flew back to the coast of England at a speed of 541mph and the descent back to the home base was flown as a glider. The mission was estimated for 21 minutes.
Although the Arado Ar 234R-1B project was promising it was abandoned in favor of the DFS 228 reconnaissance rocket-driven glider giving even better ceiling of 75,460 ft (Ref: 16).
POWER PLANT: Two Junkers Jumo 004B-2 turbojet engines, rated at 900 kp each
PERFORMANCE: 510 mph at 32,800 ft
COMMENT: Another development of the Messerschmitt Me 262A-1a series was the Messerschmitt Me 262A-1a/U3 reconnaissance fighter. Several aircraft featured a bay in the nose for two side-by-side obliquely-mounted cameras. These could be two Rb 50/30s or an Rb 20/30 and a Rb 75/30. A small observation window was introduced into the floor of the cockpit. Due to the size of the cameras two bulge at both sides of the nose were installed. Because of the high speed all cannon armament was discarded. These aircraft were deployed to tactical reconnaissance groups (NAG = Nahaufklärergruppe) (Ref.: 7).
TYPE: Fighter, Dive bomber, Ground attack, and Reconnaissance aircraft. Project.
ACCOMMODATION: Pilot only
POWER PLANT: One BMW 801D engine, rated at 1,700 hp and one BMW 003 turbojet, rated at 800 kp
PERFORMANCE: 423 mph at 13,600 ft (estimated)
COMMENT: The Blohm & Voss Company had a great experience in designing asymmetrical aircraft as the Blohm & Voss Bv 141, Bv P. 176, Bv P.179, Bv P.204, and Bv P.237. In 1944 Blohm & Voss proposed new asymmetrical design to the RLM, which could be used as fighter, destroyer, dive bomber and reconnaissance, respectively. The design featured a mixed propulsion system with a piston engine in the main fuselage/ tail boom and a turbojet under a separated gondola that housed the cockpit. The main advantage of that arrangement was an excellent and unobstructed view for the pilot and the reduction of torque moments along the vertical axis induced by the propeller of single engine aircraft. Several different designs were proposed, the Bv P.194.01-02, the Bv P.194.03-01, and the Bv P.194.00-101, changes regarding mainly in the layout of the turbojet engine. Due to the threatening defeat of Germany the Bv P.194 development was not pursued (Ref.: 16).
POWER PLANT: Two BMW 801TJ rated at 1,890 h.p. each
PERFORMANCE: 383 m.p.h at 40,300 ft
COMMENT: The production Ju 388L-1 differed from the pre-production version Ju 388L-0 in several aspects. The wooden three-blade airscrews were replaced by VDM-Dural four-bladers, a FuG 217 “Neptun” tail-warning radar was installed and the “Waffentropfen WT81Z” (Weapon Drop), housing two fixed aft-firing MG 81 machine guns, were replaced by a large wooden ventral pannier to accommodate both cameras and a jettisonable auxiliary fuel tank. A total of 47 Ju 388L reconnaissance aircraft were delivered
ACCOMMODATION: Pilot only in prone position in pressurized cabin
POWER PLANT: One Walter HWK 109-509 bi-fuel liquid rocket engine, rated at 1,650 kp at 40,000 ft
PERFORMANCE: 559 mph (estimated)
COMMENT: The rocket-powered high-altitude reconnaissance aircraft DFS 228 (Deutsche Forschungsanstalt für Segelflug, German Institute for Sailplane Flight) was designed to climb to altitudes up to 75,459 ft and was than – due to this extreme height – far beyond the operational limits of any other aircraft at its time.
The DFS 228 design was a mid-wing monoplane, using wood whenever possible, with the exception of the pressurized nose compartment, which was an all-metal construction. Fins were plywood covered, ailerons and rudder fabric covered. A landing skid was housed in the center fuselage and could be extended for landing. For take-off a “Mistel” (Mistletoe) pick a pack configuration with landing skids retracted on a carrier Dornier Do 217K was proposed. Equipped with Zeiss infrared camera the aircraft was to be used for powerless reconnaissance missions. To perform these missions the DFS 228 was carried to an altitude of 33,000 ft. After ignition of the Walter HWK 109-509 liquid-fuel rocket engine and separation from its carrier the aircraft was able to reach its service ceiling of app. 75,000 ft within five minutes. The actual reconnaissance mission was done in powerless flight. Descending to its release height of 33,000 ft the aircraft could cover a distance of app. 466 miles and another 218 miles until landing. In case of emergency the pressurized nose compartment, equipped with all life-supporting systems, could be jettisoned by means of four explosive bolts, the module descend to an altitude at which the pilot could survive without oxygen supply. The pilot was ejected through the front windscreen and at the same time a parachute was deployed to bring the pilot safely to the ground.
By the end of WW II several prototypes had been built. However, flight testing was only performed in a non-powered glide and a height of 33,000 ft resp.75,000 ft was not exceeded (Ref 17, 24).