Just as the Jenseitsflugmaschine was put into storage, a new disk aircraft was being tested at the Arado works in Brandenburg. The Rundflugzeug (Disk Aircraft) RFZ1 suffered a disastrous control failure on its first test flight in June 1934. The craft was destroyed and the pilot barely escaped with his life, but the development of a more advanced RFZ2 was authorized.
The RFZ2 was 16 feet in diameter and had an improved vril drive with a magnetic-impulse steering unit. It was used for fast reconnaissance during the Battle of Britain, and its success led to the inception of the Vril project.
While other saucer projects focused on advanced technologies, the BMW Flügelrad (Flying Wheel) prototypes were developed with more immediate goals in mind. Powered by jet engines and using a conventional disk-rotor, the Flügelrad was essentially a rotorcraft with a centrally-placed cabin, using the wash from the jet engines to drive the rotor.
Work began in 1943 and four prototypes were built. The early prototypes were pure disks, but later models had a tail added to improve lateral control. Despite its modest goals compared to the Vril and Haunebu programs, the Flügelrad project did not result in a flyable aircraft; ducting the jet wash through the lifting rotor caused control and stability problems that had not been overcome when the Red Army overran the Prag-Kbley testing facility.
Developed by the Vril Society from designs allegedly obtained psychically from the advanced Aryan civilization in the Aldebaran system, the Vril Triebwerk motor used contra-rotating metal disks studded with electromagnets which rotated at high speed. The interaction of their magnetic fields created an oscillation that was gradually intensified until it could warp space-time and create a wormhole to the desired destination.
While there is no documented proof that this was actually achieved, the electromagnetic-gravitic drive allowed a saucer craft to reach previously unheard-of speeds — up to Mach 10 according to some reports. The Triebwerk’s gravitic warping also permitted a craft to change velocity and direction instantly, without subjecting the airframe or crew to G-forces that would be fatal under normal circumstances.
Working in occupied Prague, Rudolf Schriever and Klaus Habermohl developed a disk-shaped craft that consisted of a ring of turbine blades that rotated around a fixed central cockpit. The craft proved both fast and agile, and the Schriever-Habermohl project was quickly absorbed by SS E-IV. Under Kammler’s personal direction a hand-picked team of engineers from all over the Reich worked to refine the airframe design and propulsion systems, and added a variety of armament including the Feuerball (Fireball) electrostatic weapon.
The resulting series of aircraft were given the name Haunebu or Hauneburg-Gerät (Hauneburg Device). Hauneburg was a wholly fictional name and did not refer to any place or person; it was coined simply to confuse and deceive Allied intelligence. There have been some claims that the project was moved to a remote testing-ground codenamed Hauneburg, but up to the time of writing not a single Nazi-era document has been recovered that uses the name Hauneburg as a place-name.
A breakthrough was achieved when the Shriever-Habermohl airframe was mated with a Thule-developed electromagnetic-gravitic propulsion system named Tachyonator-7. Test flights using this drive recorded speeds of up to Mach 2 and a climb rate of almost 14,000 feet/minute — more than five times the climb rate of a Spitfire. Early tests also reached altitudes in excess of 40,700 feet, which was far beyond the reach of the best Allied aircraft.
After the encouraging results of these early tests, Kammler authorized a full-scale development effort. The two Haunebu I prototypes were larger than the Shriever-Habermohl airframe and made of a specially-developed alloy codenamed Victalen. They were 81 feet in diameter — a little longer than a B-17 Flying Fortress — and according to some reports could reach speeds close to Mach 4.
For weapon tests, the second prototype was fitted with a turret mounting twin 60mm Kraftstrahlkanone (KSK) energy-beam weapons, but firing them caused a massive energy drain which led to stability problems and subsequent tests used two packs of three MK 108 30mm cannon, which was standard armament for many German fighters.
At 85 feet diameter, the Haunebu II was only slightly larger than its predecessor and incorporated only minor improvements.
Testing between 1942 and 1944 led to the development of the Haunebu II Do-Stra (Dornier Stratosphären Flugzeug: Dornier Stratospheric Aircraft). Although it was classified as a development of the Haunebu II, the Do-Stra was effectively a different craft. The Haunebu II’s Mach 5 performance was increased to a staggering Mach 17, and it was armed with seven pairs of Kraftstrahlkanone: three pairs of 80mm weapons turret-mounted on the craft’s underside and a single 110mm KSK mounted above the cockpit.
This was the first Haunebu craft considered ready for large-scale manufacturing. Both Junkers and Dornier tendered for the contract in late 1944, and as the name suggests it was Dornier’s bid that was accepted by the Air Ministry. However, Allied strategic bombing prevented Dornier from completing more than a handful of craft: the exact number is still unknown.
The Haunebu III was a quantum leap from the Do-Stra. Nicknamed “Ostara” after an ancient Germanic goddess, it was three times the size of its predecessors and almost twice as fast. It also mounted a fearsome armament: no fewer than 22 KSKs between 50mm and 110mm, plus 60 MK 108 30mm cannon.