Secret Weapons of the Luftwaffe, Part 5
by Jim "Twitch" TittleArticle Type: Military History
Article Date: May 17, 2002
I Need A Plane
While Herman Göring led the Luftwaffe his intermediary was the Air Ministry that took his want list and attempted to make it reality by interfacing with manufacturers. If a certain type of aircraft was desired Göring would put down the specifications and the Ministry would draw them up as technical requirements and pass them on to aircraft builders. If they thought they could create the said aircraft they presented a proposal to the Ministry with as specific as possible performance data, based on their expertise. The “P” before most numbers stands simply for Projeckt. When a project was accepted a company designation was attached.As the war unfolded the Air Ministry would put forth specification criteria for aircraft that they in their alleged expertise thought Germany should have.
In the latter stages of the war Albert Speer headed the ministry due to his ability to generally keep all German industry humming. Aircraft requirements were now concentrated on interceptor types. Sometimes balanced designs were compromised or deliberately overlooked for unknown reasons. Planes were built that had little value. Promising types were not. Such is the case if one tries to open the champagne bottle, fussing with the cork, at a minute to midnight on New Year’s Eve.
Blohm & Voss Abteilung Flugzeugbau - Hamburg
P.211
Head designer Richard Vogt, discussed in SWOTL IV, had a few jet designs for the Air Ministry. When the requirement for the “People’s Fighter” came down in September 1944 he produced a better layout, in this author's opinion. His Project 211 mounted the engine where it belonged, inside the fuselage, aft of the cockpit. His design was judged best but Heinkel had built a mock up of the He 162 and was awarded the contract.
The P.211 made the jet intake part of the load-bearing structure for all-around greater strength. The intake in the nose was a good way to ingest air and cleaner. The wings and tail were not swept. The dimensions are not to be found but look to be similar to the He 162’s 24-foot span and 29-foot length.
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| Vogt's P.209 & P.211 |
Power came from the forthcoming BMW 003D turbojet of 2,425 lbs. thrust. At 4,400 lbs. it was planned lighter than the 7,500 lb. loaded He 162. Estimates for a 537 MPH top speed at 26,248 feet was planned and the 2 X 30mm Mk 108 cannon with 60 rpg were the required armament. Vogt designed it with 58 percent steel, 13 percent Duralumin and 68 percent miscellaneous materials, such as wood.
P.213
Yet another, even simpler to construct fighter requirement was put forth in the “Miniature-Jäger” or Miniature Fighter. This directive included that the design be laid out around the V-1’s Argus 660 lb. thrust pulsejet. The concept was for cheap, numerous interceptor fighters to swarm the bomber formations and attack using a single Mk 108 with 135 rounds. (See “SWOTL IV” and the Me 328) An armored steel fuselage would be augment with wooden wings. The tricycle landing gear and cannon were to be operated with compressed air.
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| Model Of The P.213 Mini-Fighter |
Vogt’s design had the tail pipe of the Argus protruding out of the tiny egg-like fuselage pod with a boom extending above it with a length of 20.4 feet. Non-swept wings had a span of 19.8 feet. A down dihedral V tail with no vertical stabilizer rode the end of the fuselage boom. Speed at sea level was projected at 435 MPH with a climb of 3,936 fpm and a ceiling of 32,810 feet. Range would have been 775 miles. The P.213 designation was to be catapulted to reach the minimum operating speed of 149 MPH for the pulsejet. The concept was not pursued as the Bachem Ba 349 “Natter” was chosen for the task. (See “SWOTL I” for more details.)
P.209
Vogt’s best jet design was the Project 209, however. It fulfilled an Air Ministry niche for the “Schnellstjäger” or high speed fighter. He already had this one drawn up when the specs were announced. A single Heinkel-Hirth HeS 011 of 2,866 lbs. thrust was the power plant. Its 26.6-foot wings were swept forward like the Ju 287 bomber. The intake in front led through the chubby fuselage where the exhaust terminated but a tail boom continued above just aft of the trailing wing edge where the non-swept tail immediately commenced. Again he used the turbine intake as part of the structure.
Weight was undisclosed but it could carry 164 gallons of fuel for an unknown range. Vogt was so sure of this design that he guaranteed performance to within 3 percent. He figured a ceiling of 39,700 feet and a climb rate of 5,078 FPM with a top speed of 615 MPH while armed with a pair of Mk 108 30 mms. It is not known if any design was chosen before the end of the war.
BV155
But one plane that was near completion when the Allies occupied Hamburg in May 1945 was the BV 155V4. It came from a 1943 requirement for a high altitude fighter-bomber. It was begun by Messerschmitt as the Me 155, but probably due to the feud between Willy Messerschmitt and Erhard Milch heading the Air Ministry, it was ordered completed by Blohm & Voss. While some Bf 109 components remained Vogt made a vast redesign employing a laminar flow wing with two large under-slung radiators in place of Messerschmitt’s eight. A P-51-style third radiator was added under the fuselage. An all-around vision canopy replaced the original in the pressurized cockpit.
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| BV 155V4 Was A Real Deal |
The big wings measured a span of 67.2 feet while length was 39.25 feet. The ship weighed 12,390 lbs. loaded. The Daimler Benz 603 was retained and a TK 15 turbo-supercharger produced 1,810 HP with the 603U. Armament was a single 30 mm Mk 103 or 108 with 60 rounds and two MG 151 20 mm cannon with 200 RPG. A 2,200 lb. bomb load was originally specified as well.
But the V4 prototype’s astonishing performance was quite superior in the area of altitude predicted. A maximum ceiling of 56,100 feet was projected! Speed was there with 373 MPH at 30,000 feet and 428 MPH at 50,000 feet! Range was 838 miles. Flight test were set to commence when the collapse came. Thirty planes were on order. Four prototypes were made with the V4 ready to fly. The V1 had flown in September 1944 with the V2 in February 1945 above 40,000 feet. The V3 was incomplete.
Bley Segelflugzeugwerke - Naumburg
Sombold P.344
Luftwaffe pilots had a phrase for the B-17 and B-24 formations: “Feurspeidenden Berg” or fire-spitting mountains. If a formation could be broken up interceptors could attack single bombers with less risk since a box of them could generally bring sixty-four .50 guns to bear on an attacker. Heinz Sombold had an idea to break up these formations. He first conceived a towed rocket plane intercept and then the dropping of a bomb at a 45-degree angle set to detonate at the bomber’s altitude. After scattering the heavies, regular interceptors could then attack. The bomb hurler would glide back and land on its skid.
By January 1944 the Air Ministry had several weapons that could adapt to Sombold’s concept. Most likely ordnance was an adaptation of the Fritz Z-type guided bomb. Instead of the SD. 1400X or Fritz X with an anti-armor warhead, the Z had an explosive flak nose. This tactical flak weapon would be launched about 3,000 yards above and behind the intended formation. Using the Telefunken-Staru FuG 203/230 radio control in the launch vehicle the bomb could be guided accurately and detonated by remote control.
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| Drawing of Sombold's P.344 |
No substantial specifications remain on the P.344 other than the motor being the Walter HWK 509A bi-fuel liquid rocket giving 3,748 lbs. thrust in a vehicle of the same general size as the Bachem Ba 349. When looking at the line drawing that would make the P.344 about 20.0 feet long with a bit larger wingspan of, maybe, 18.0 feet. The rocket would give a speed of, perhaps, 550 MPH with a burn duration of 3-4 minutes. Using the modified SD. 1400 type bomb weighing 3,000 lbs with at 595-pound warhead, the plane would likely be about 3,000 lbs. itself.
Certainly other projectiles would lend themselves to this launcher. Several rocket powered missiles could be used that were in final development at the end of the war. Ships would be fair targets using the SD. 1400X in this plane too.
Zeppelin Abteilung Flugzeugbau GmbH - Fredrichshafen
Project Rammer/Sideswiper
So what ever happened to the builders of the airships, Zeppelin? They were still around by WWII building sub-assemblies for larger aircraft and other bit and pieces. With the colossal numbers of heavy bombers converging regularly on Germany, various methods to stop them were dreamed up. Kamikaze attacks were ruled out by the Air Ministry, though proponents like aviatrix Hanna Reitsch argued her position till the end of the war.
Zeppelin suggested an alternative with a small solid fuel rocket powered craft capable of ramming one or two heavy bombers and surviving. It was feasible to build a plane so strongly that it could cut off another B-17’s tail after firing its salvo of fourteen R4M 55 mm rockets at a formation. A steel fuselage and wings with three tubular spars would do the job. The Rammer/Sideswiper idea was born.
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| Zeppelin's Tiny Rammer |
It was 16.1 feet long and the design had a 16.4-foot non-swept wing constructed so solidly that it could perform mid-air slice of a bomber’s tail and survive. Again the concept was to tow the craft aloft and wait for the bomber stream to appear. The pilot, flying from his prone position, would then light his Schmidding 533 rocket of 2,205 lbs. thrust and close on the bombers at 600 MPH at the peak speed upon spending his solid fuel. Burn time of this rocket is unknown but typically would be about 45-60 seconds.
The nine-pound R4M rockets with their 1.1-pound warheads were the same as used on Me 262s, which carried twenty-four. Maximum range of the R4M was 4,900 feet but effective range was 1,800 feet. Its tiny size would be hard to hit by gunners it was reasoned. But protection for the pilot beyond heavy armor was a windscreen with 80 mm glass plate and side panels with 40 mm glass. The nose and leading wing edges were to be fabricated of 20-30 mm cannon-proof hardened steel. The plane would glide to land on its retractable skid anywhere it could for later retrieval.
The Air Ministry never had time to decide on which manufacturer’s design to choose. No prototypes or mock-ups are known to have been constructed.
Dornier Werke Gmbh - Friedrichshaften
P.254
We touched on the Do 252 in “SWOTL, Part II” mounting both DB V-12s in tandem at the rear for a better balanced plane than the original Do 335. What is not commonly known was another Dornier design to meet the Air Ministry’s demand that all new designs be jet powered, which the 335 was not. Fearing cancellation of the 335 for the Ta 152 Claudius Dornier produced a layout as a stopgap plane before a pure jet design in the Do P.254.
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| Dornier's P.254 With Jet Pusher |
Dornier, born in 1884, worked with Zeppilin early on but Count Zeppelin assisted in the foundation of Dornier Metallbauten GmbH. There Dornier worked on stress, aerodynamic, metallurgy and hydrodynamics—all useful stuff applied to his later flying boats, and bombers. He had no interest in jet design and his first was in 1945, when it was too late anyway. He survived the war and built Luftwaffe F-104s in 1955 and a VTOL transport plane prototype, the Do 31. Claudius Dornier died in 1969.
During the war the cancellation of the “Ural Bomber” left Dornier behind most of the other German companies. The Ministry had decreed he was supposed to work on bomber designs only. But the P.254 was a clever design, which used basic, existing Do 335 structure with its 2,300 DB 603A V-12 pulling and one HeS 011 jet of 2,855 lbs. thrust pushing. How much faster than the Do 335’s 474 MPH this combination would have given is not known.
P.256
The February 1945 requisite for a twin jet night and dirty weather fighter allowed Dornier to again use his basic 335 layout with only a slightly increased wingspan to 50.9 feet while length was the same at 45.3 feet. The wings still had a swept leading edge but were otherwise straight. The same tricycle undercarriage was retained and provision for six 30 mm Mk 108s with 120 RPG in the nose was made.
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| Dornier P.256 |
The duo of HeS 011s rested beneath the wings. The fuselage and tail looked like a scaled down B-26’s. In the pressurized cabin pilot and radar operator sat side by side while the navigator sat behind them near the trailing edge of the wing. Speed was foreseen as 516 MPH with a ceiling of 41,013 feet and a range of 874 miles from the 26,896 lb. plane. Two 1,102 lb. bombs could be carried.
It is interesting to note for the time that the design was not judged apt since it had un-swept wings! No wing re-work was done before the war’s end. The Douglas Skyknight of the 1950's was quite similar in performance and role.
First Air-To-Air
The Hs 298 predated the better wire-guided X-4. This was the world’s first air-to-air missile to be developed and built. The first launch of an Hs 298 was on December 22, 1944 from a Ju 88 A-4. More than 300 Hs 298 missiles were fired during extensive testing at Karlshagen from Ju 88G, Ju 388, and FW 190s. A wire-guided version Hs 298 V2, with a much larger warhead of 106 lbs., was also developed and briefly tested before war’s end. This weapon never reached Luftwaffe units. Though the X-4 did.
With a weight of 210 lbs. including the 55-lb. warhead the missile was 6.6 feet long with 4.1-foot wings. Wire spools uncoiled for control in flight, which reached 455 MPH in its one-mile range.
Rheinbote
The Rheinbote was a four-stage, unguided long-range artillery missile. It was a solid-fuel missile with very slim proportions. It was 35 feet long, weighed 3,773 lbs. at launch, and had a range of 133 miles but its warhead was only 97 lbs. About 200 were fired at Antwerp in late 1944.
Kramer X-7 Rotkappchen
There was an anti-armor guided missile actually used also. This was a wire-guided anti-tank missile. The X-7 Rotkäppchen had a short, fat body, large twin fins, and a trailing arm carrying the guidance wire spool. It had a 5.5 lb. shaped-charge warhead. Small numbers of pre-production missiles were used in combat but no details are avaiable. There was also a Steinbock version with IR homing guidance
How Far?
Between 1942-45 Aerodynamic Research Laboratories at Peenemünde developed The Peenemünde Arrow Shells that were hyper speed projectiles made for smooth bore German artillery weapons. The project was initially visualized and designed as ultra-long-range shells using a 31 cm smooth-bored version of the famed 28 cm K5 railway gun dubbed Anzio Annie. The arrow shell was 75 inches long and 120 mm in caliber diameter. Four fins at the tail measured 31 cm across with a 31 cm sabot around the middle of the shell at the center of gravity. The sabot skirt would allow acceleration of the shell throughout the length of the barrel travel and was discarded as the shell left the muzzle at a 5,000 FPS velocity giving a range of 94 miles! A pair of these guns were produced and successfully fired at U.S. forces from 78 miles distance.
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| Static 14-Inch 'London Gun' |
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| Details Of The Skirt |
An AA round was produced for the FLAK 39 105 mm gun. Its purpose was to speed up flight of the projectile to altitude shortening the time needed to calculate and zero-in between rounds. The faster round would need less lead since its aim point could be closer to target regardless of its speed too. 3,500 FPS was obtained with this shell but production was not possible since industry was full up with production of war material.
Sabot rounds are used today in modern tanks.
Read all the Secret Weapons of the Luftwaffe Articles:
Sources
- Aeronautical Staff of Aero Publishers, Inc.
Kamikaze
Aero Publishers, Fallbrook, CA 1966
- Green, William
Fighters Vol. 1
Doubleday & Co. NY, 1960
- Green, William
Jets Aircraft of the World
Macdonald, London, 1955
- Green, Wm.
The Complete Book of Fighters
Smithmark Publishers, NY, 1994
- Myhra, David
Secret Aircraft Designs of the Third Reich
Schiffer Publishing, 1998
- Nowarra, Heinz J.
The Messerschmitt 109
Harleyford Publications GB 1964
- Pocock, Rowland, F.
German Guided Missiles
Arco Publishing Co., Inc, N.Y. 1967
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