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Thursday, March 10, 2011

Wehrmacht Secret Weapons.






Messerschmitt Me P 1070

Development of the Messerschmitt Me 262 presented to the involved design engineers/technicians difficult tasks in various areas (e.g. the usage of a nose-wheel instead of the traditional tail-wheel). In order to facilitate the development/production of the new airplane, some alternative solutions to the Me 262 were devised by Messerschmitt. The Messerschmitt Me P.65 can be seen as a pre-development study, but Me P.1065 and Me. P.1070 were real alternative developments. Me. P.1065 would incorporate substancial features of Me 262 as fuselage, major parts of the empennage and construction would be facilitated by the usage of a tail-wheel. The turbo-jet engines were not to be placed beneath the wings, but were to be integrated within the wing-structure. This alternative airplane proposal didn't find approval by the German Air Ministry (Reichsluftfahrtministerium, RLM) and therefore didn't proceed beyond the drawing boards. 
Messerschmitt's Projekt 1070 was designed parallel to the famous Me 262 and was quite similar in appearance. However, the Me 262 proved to be superior and the Me P 1070 never left the drawing board.
This machine features in John Baxter's latest book "The Alternate Luftwaffe 2" as the fictional Me 260 A-1/R1 of the Romanian Royal Air Force, battling Soviet bombers over Ploiesti.













Messerschmitt Me P 1091

In 1942 the RLM announced the need for a new Special High Altitude Fighter. This fighter should be ready for operations late in 1944. In order to provide a quick solution to the problem, Messerschmitt offered a design based on the 109, the P-1091. This was in fact a stretched 109 in which the wings and the rear fuselage were enlarged. This aircraft was to have been powered by the DB 605 engine and armed with three MG 151 machine guns.
During the first half of 1943, Messerschmitt's design engineers had evolved basic parameters of an (extreme high altitude fighter) design study under the company designation Me P1091.

By the summer of 1943 it became clear that a higher operational altitude would be necessary. This led to the P-1091a which was similar to the P-1091 but powered by the DB 603U or DB 632. This last engine was an adaptation of the DB 603, designed for the use of two 4-bladed contra-rotating propellers.

As it became clear that the P-1091 could not be realized within a reasonable period of time, a new design was proposed. This was based on the Me-109H using a DB 628 engine. Contrary to the orders of the RLM, Messerschmitt continued the work on the P-1091, developing it into the P-1091b OR Me209H however.

To test the DB 628 engined design a mock-up of the engine installation was made in the Me-109 V-49, based on a G-5 airframe. The DB 628 was flight tested in the Me-109 V-50 and V-54. After the tests with the V-54, Messerschmitt abandonned all projects with the DB 628. The DB 628 program was cancelled in 1944. 






Messerschmitt Me P.1101

Messerschmitt P.1101 was the name attached to a single-seat, single-jet fighter developed in response to the July 1944 Emergency Fighter Program, which sought the second generation of jet fighters for the Third Reich. A characteristic feature of the P.1101 prototype was that the sweep of the wings could be changed before flight, a feature perfected by the later Variable-sweep aircraft such as the Panavia Tornado, MiG-23, Bell X-5, F-111 Aardvark and the F-14 Tomcat.

Within nine days of the 15 July 1944 issuance of the design specifications for the Emergency Fighter, the Messerschmitt design bureau under Woldemar Voigt had formed a preliminary paper design for the P.1101. The aircraft which was developed initially had a short and wide fuselage, tricycle landing gear, and mid-mounted wings with an inner sweep of 40 degrees near the fuselage, and a shallower 26 degree angle outboard. The single He S 011 jet engine was to be mounted internally within the fuselage, being aspirated by two rounded intakes located on either side of the cockpit. The tail was of a V configuration, and mounted on a tapered boom which extended over and past the jet exhaust, while the cockpit was forward mounted, with the canopy integrated into the fuselage and forming part of the rounded nose of the aircraft.


By late August 1944, the design still in paper form had evolved into a sleeker incarnation, with the previously stout fuselage lengthened and narrowed with a conical nose section added in front of the cockpit. The double angled wing was also abandoned, with the outer wing of the Me 262 instead being adapted for the design. The design was further developed, and after the wind tunnel testing of a number of wing and fuselage profiles, the design was further modified and finalized, with the decision made to undertake the construction of a full-scale test aircraft. This finalized design and associated test data were submitted to the Construction Bureau on 10 November 1944 and the selection of production materials was begun on 4 December 1944.


On 28 February 1945, the RLM settled on a competing design, the Focke-Wulf Ta 183, as the winner of the Emergency Fighter program. This decision was based in part on the considerable design difficulties being encountered by the Messerschmitt P.1101 design team. For example, the cannon installation was proving too crowded, the mainwheel retraction and door mechanisms were too complex, the fuselage needed a great number of "strong points" to deal with loads, and the anticipated performance had fallen below the RLM specifications due to increased weight.









 Me 163 Komet

The Me 163 Komet was perhaps the most unique aircraft design of the World War II.

Designed by Alexander Martin Lippisch, was a German rocket-powered fighter aircraft. As of 2011, it remains the only rocket-powered fighter aircraft to have ever been operational. Its design was revolutionary, and the Me 163 was capable of performance unrivaled at the time. Messerschmitt test pilot Rudy Opitz in 1944 reached 1,123 km/h (698 mph). Over 300 aircraft were built, however the Komet proved ineffective as a fighter, having been responsible for the destruction of only about nine Allied aircraft (16 air victories for 10 losses, according to other sources).

The most famous Komet must surely be the red Komet in which EK16 commander Wolfgang Späte flew the first operational mission with a Komet. Without his knowledge, the ground crew painted his aircraft bright red, similar to Von Richthofen's red aircraft in WW1. Apparently confidence in the Komet's invulnerability was high! According to his own accounts, Späte was not amused, and ordered the paint to be removed after the flight.

Späte writes that V41 still had MG 151/20 armament. This means the gun barrels project from the wing's leading edge, but also the ammunition hatch on the spine is different compared to the later MK 108 armed Komets. See 'White 54' for a Komet with this type of hatch. This aspect is often overlooked by both kit manufacturers and modellers. Another aspect of early Komets are the smaller span trim surfaces (the inboard surfaces). This is shown clearly on this Komet. It's a small modification, but again it is often overlooked. It was overlooked by the artist of the above drawings. The cooling air inlet on the extreme rear fuselage exists in many variations, but my guess would be that it was the same type as seen on PK+QP ('White 05') and 'White 54'. For the tail wheel, I would expect a faired tail wheel.


Work on the design started under the aegis of the Deutsche Forschungsanstalt für Segelflug (DFS) - the German Institute for the Study of sailplane flight. Their first design was a conversion of the earlier Lippisch Delta IV known as the DFS 39 and used purely as a glider testbed of the airframe.


A larger follow-on version with a small propeller engine started as the DFS 194. This version used wingtip-mounted rudders, which Lippisch felt would cause problems at high speed. He later redesigned them to be mounted on a conventional vertical stabilizer at the rear of the aircraft. The design included a number of features from its glider heritage, notably a skid used for landings, which could be retracted into the aircraft's keel in flight. For takeoff, a pair of wheels, each mounted onto the ends of a specially designed cross-axle, together comprising a takeoff "dolly" mounted under the landing skid, were needed due to the weight of the fuel, but these were released shortly after takeoff. It was planned to move to the Walter R-1-203 cold engine of 400 kg (880 lb) thrust when available.


Heinkel had also been working with Hellmuth Walter on his rocket engines, mounting them in the He 112 for testing, and later in the first purpose-designed rocket aircraft, the He 176. Heinkel had also been selected to produce the fuselage for the DFS 194 when it entered production, as it was felt that the highly volatile fuel would be too dangerous in a wooden fuselage, with which it could react
Work continued under the code name Projekt X.




However the division of work between DFS and Heinkel led to problems, notably that DFS seemed incapable of building even a prototype fuselage. Lippisch eventually requested to leave DFS and join Messerschmitt instead. On 2 January 1939, he moved along with his team and the partially completed DFS 194 to the Messerschmitt works at Augsburg.


The delays caused by this move allowed the engine development to "catch up". Once at Messerschmitt, the decision was made to skip over the propeller-powered version and move directly to rocket power. The airframe was completed in Augsburg and shipped to Peenemünde West in early 1940 to receive its engine. Although the engine proved to be extremely unreliable, the aircraft had excellent performance, reaching a speed of 342 mph (550 km/h) in one test.




Production of a prototype series started in early 1941, known as the Me 163. Secrecy was such that the number, 163, was actually that of the earlier, pre-July 1938 Messerschmitt Bf 163 project to produce a small two-passenger light plane, which had competed against the Fieseler Fi 156 Storch for a production contract. It was thought that intelligence services would conclude any reference to the number "163" would be for that earlier design. The Me 163 A V4 was shipped to Peenemünde to receive the HWK RII-203 engine on May 1941. By 2 October 1941, the Me 163 A V4, bearing the radio call sign letters, or Stammkennzeichen, "KE+SW", set a new world speed record of 1,004.5 km/h (624.2 mph), piloted by Heini Dittmar. 


This would not be officially approached until the postwar period by the new jet fighters of the British and U.S., and was not surpassed until the American Douglas Skystreak turbojet-powered research aircraft did so on 20 August 1947. Five prototype Me 163 Anton A-series experimental V-aircraft were built, adding to the original DFS 194 (V1), followed by eight pre-production examples designated as "Me 163 A-0".


During testing, the jettisonable main landing gear arrangement was a serious problem. The landing gear caused many aircraft to be damaged at takeoff, when the wheels rebounded and crashed into the aircraft. Malfunctioning hydraulic dampers in the skid could cause back injuries to the pilot when landing, as the aircraft lacked steering or braking control during landing, and was unable to avoid obstacles. Once on the ground, the aircraft had to be retrieved by a tractor-like vehicle, towing a special retrieval trailer that rolled on a pair of short continuous-track setups (one per side), with twin trailing lifting arms, that lifted the stationary aircraft off the ground, from under each wing. The tractor was originally meant for agricultural use, the three-wheeled Scheuch-Schlepper, as the Komet was unpowered and lacked wheels at this point.


During flight testing, the superior gliding capability of the Komet proved detrimental to safe landing. The aircraft would rise back into the air with the slightest updraft. Since the approach was unpowered, there was no opportunity to make another landing pass. For production models, a set of landing flaps allowed somewhat more-controlled landings. This issue remained a problem throughout the program.
Nevertheless, the overall performance was tremendous, and plans were made to put Me 163 squadrons all over Germany in 40-kilometre rings (25 mi). Development of an operational version was given the highest priority.



Meanwhile, Walter had started work on the newer HWK 109-509 hot engine, which added a true fuel of hydrazine hydrate and methanol, designated C-Stoff, that burned with the oxygen-rich exhaust from the T-Stoff, used as the oxidizer, for added thrust. This resulted in the significantly modified Me 163 B of late 1941. Due to the Reichsluftfahrtministerium (RLM) requirement that it should be possible to throttle the engine, the original power plant grew complicated and lost reliability. The new fuel proved an unfortunate choice as well, since hydrazine hydrate was also used in the launcher of the V-1 "Doodlebug" flying bomb and was in short supply throughout the 1943-45 period.


The fuel system was particularly troublesome, as leaks experienced during hard landings easily caused fires and explosions. Metal fuel lines and fittings, which failed in unpredictable ways, were used as this was the best technology available. Both fuel and oxidizer were toxic and required extreme care when loading in the aircraft, yet there were occasions when Komets exploded on the tarmac. The corrosive nature of the liquids required special protective gear for the pilots.


Two prototypes were followed by 30 Me 163B-0 aircraft armed with two 20 mm MG 151/20 cannon and some 400 Me 163B-1 planes armed with two 30 mm (1.18-inch) MK 108 cannons, but which were otherwise similar to the B-0. Occasional references to B-1a or Ba-1 subtypes are found in the literature on the aircraft, but the meanings of these designations are somewhat unclear. Early in the war, when German aircraft firms created versions of their aircraft for export purposes, the a was added to export (ausland) variants (B-1a) or to foreign-built variants (Ba-1) but for the Me 163, there were neither export nor a foreign-built version. Later in the war, the "a" and successive letters were used for aircraft using different engine types: as Me 262A-1a with Jumo engines, A-1b with BMW engines. As the Me 163 was planned with an alternative BMW P3330A rocket engine, it is quite safe to assume the "a" was used for this purpose on early examples. Only one Me 163, the V10, was tested with the BMW engine, so this designation suffix was soon dropped. The Me 163 B-1a didn't have any wingtip "washout" built into it, and as a result, it had a much higher critical Mach number than the Me 163 B-1.


The Me 163B had very docile landing characteristics, mostly due to its integrated leading edge slots, located directly forward, along the wing's leading edge, of the elevon control surfaces. It would neither stall nor spin. One could fly the Komet with the stick full back, and have it in a turn and then use the rudder to take it out of the turn, and not fear it snapping into a spin. It would also slip well. Because it was derived from a glider, it had excellent gliding qualities, and had tendency to continue flying above the ground due to ground effect. On the other hand, making a too close turn from base onto final, the sink rate would increase, and one could quickly lose altitude and come in short. Another main difference from a propeller-driven aircraft is that there was no slipstream over the rudder. On takeoff, one had to attain the speed at which the aerodynamic controls become effective - about 129 km/h (80 mph) - and that was always a critical factor. Pilots used to flying propeller driven aircraft had to be careful the control stick wasn't somewhere in the corner when the control surfaces began working. These, like many other specific Me 163 problems, would be resolved by specific training.


The performance of the Me 163 far exceeded that of contemporary piston engine fighters. At a speed of over 320 km/h (200 mph) the aircraft would take off, in a so-called "sharp start" from the ground, from its two-wheeled dolly. The aircraft would be kept at low altitude until the best climbing speed of around 676 km/h (420 mph) was reached, at which point it would jettison the dolly, pull up into a 70° angle of climb, and rapidly climb to a bomber's altitude. It could go higher if required, reaching 12,000 m (39,000 ft) in an unheard-of three minutes. Once there, it would level off and quickly accelerate to speeds around 880 km/h (550 mph) or faster, which no Allied fighter could match. The usable Mach Number was similar to the Me-262, but because of the high thrust to drag ratio, it was much easier for the pilot to lose track of the onset of severe compressibility and loss of control. A Mach warning system was installed as a result. The aircraft was remarkably agile and docile to fly at high speed. According to Rudolf Opitz, chief test pilot of the Me 163, it could "fly circles around any other fighter of its time".


By this point, Messerschmitt was completely overloaded with production of the Bf 109 and attempts to bring the Me 210 into service. Production in a dispersed network was handed over to Klemm, but quality control problems were such that the work was later given to Junkers, who was, at that time, underworked. As with many German designs of World War II, parts of the airframe (especially wings) were made of wood by furniture manufacturers.



The older Me 163A and first Me 163B prototypes were used for training. It was planned to introduce the Me 163 S, which removed the rocket engine and tank capacity and placed a second seat for the instructor above and behind the pilot, with its own canopy. The 163 S would be used for glider landing training, which as explained above, was essential to operate the Me 163. It appears the 163 Ss were converted from the earlier Me 163B series prototypes.
In service, the Me 163 turned out to be difficult to use against enemy aircraft. Its tremendous speed and climb rate meant a target was reached and passed in a matter of seconds. Although the Me 163 was a stable gun platform, it required excellent marksmanship to bring down an enemy bomber. The Komet was equipped with two 30 mm (1.18 inch) MK 108 cannons which had a relatively low muzzle velocity, with the characteristic ballistic drop of such a weapon. The drop meant they were only accurate at short distance, and that it was almost impossible to hit a slow-moving bomber when the Komet was traveling very fast. Plus, four or five hits were typically needed to take down a B-17.


A number of innovative solutions were implemented to ensure kills by less experienced pilots. The most promising was a unique weapon called the Sondergerät 500 Jägerfaust. This consisted of a series of single-shot, short-barreled 50 mm (2-inch) guns pointing upwards. Five were mounted in the wing roots on each side of the aircraft. The trigger was tied to a photocell in the upper surface of the aircraft, and when the Komet flew under the bomber, the resulting change in brightness caused by the underside of the aircraft could cause the rounds to be fired. As each shell shot upwards, the disposable gun barrel that fired it was ejected downwards, thus making the weapon recoilless. It appears that this weapon was used in combat only once, resulting in the destruction of a Halifax bomber, though other sources say it was a Boeing B-17.



The biggest concern about the design was the short flight time, which never met the projections made by Walter. With only seven and a half minutes of powered flight, the fighter truly was a dedicated point defense interceptor. To improve this, the Walter firm began developing two more advanced versions of the 509A rocket engine, the 509B and C, each with two separate combustion chambers of differing sizes, oriented one above the other, with greater efficiency. The upper chamber, intended as the motor's primary power output, was larger, and supported by the "thrust tube" exactly as the 509A motor's single chamber had been. It was tuned for "high power" for takeoff and climb. The smaller-volume, lower chamber, with approximately 400 kg (880 lb) of thrust at its top performance level, was intended for more efficient, lower-power cruise flight. 


This HWK 109-509 C would improve endurance by as much as 50%. Two 163 Bs, models V6 and V18, were experimentally fitted with the new engine, a retractable tailskid, and tested in spring 1944. On 6 July 1944, the Me 163 B V18 (VA+SP) set a new world speed record of 1,130 km/h (702 mph), piloted by Heini Dittmar, and landed with almost all of the vertical rudder surface broken away from flutter. This record was not broken in terms of absolute speed until 6 November 1947 by Chuck Yeager in a flight that was part of the Bell X-1 test program, with a 1,434 km/h (891 mph), or Mach 1.35 supersonic speed, recorded at an altitude of nearly 14,820 m (48,620 ft) altitude.


However, the X-1 never exceeded Dittmar's speed from a normal runway liftoff. Heini Dittmar had reached the 1,130 km/h (702 mph) performance, after a normal "sharp start" ground takeoff, without an air drop from a mother ship. Neville Duke exceeded Heini Dittmars record mark in 31 August 1953, with the Hawker Hunter F Mk3 at a speed of 1,171 km/h (728 mph), after a normal ground start. Aircraft of the configuration the Me 163 used were found to have serious stability problems when entering transonic flight, like the similarly configured, and turbojet powered, Northrop X-4 Bantam and de Havilland DH 108, which made the V18's record with the Walter 509C "cruiser" rocket more remarkable.


Waldemar Voigt (aerospace engineer) of Messerschmitt's Oberammergau project and development offices started a redesign of the 163 to incorporate the new engine, as well as fix other problems. The resulting Me 163 C design featured a larger wing through the addition of an insert at the wing root, an extended fuselage with extra tank capacity through the addition of a "plug" insert behind the wing, and a new pressurized cockpit topped with a bubble canopy for improved visibility. The additional tank capacity and cockpit pressurization allowed the maximum altitude to increase to 15,850 m (52,000 ft), as well as improving powered time to about twelve minutes, almost doubling combat time (from about five minutes to nine). Three Me 163C-1a prototypes were planned, but it appears only one was flown, without its intended engine.


By this time the project was moved to Junkers. There, a new design effort under the direction of Heinrich Hertel at Dessau attempted to improve the Komet. The Hertel team had to compete with the Lippisch team and their Me 163C. Hertel investigated the Me 163 and found it was not well suited for mass production and not optimized as a fighter aircraft, with the most glaring deficiency being the lack of retractable landing gear. For this, the Me 163V-18 was equipped with a non-retractable tricycle landing gear. (This prototype is often called the "Me 163D", but it is now clear that there never was a 163 D.) The resulting Junkers Ju 248 used a three-section fuselage to ease construction.


The V1 prototype was completed for testing in August 1944, and was glider tested behind a Junkers Ju 188. Some sources state that the Walter 109-509 C engine was fitted in September, but it was probably never tested under this power. At this point the RLM re-assigned the project to Messerschmitt, where it became the Me 263. This appears to have been a formality only, with Junkers continuing the work and planning production.
By the time the design was ready to go into production, the plant where it was to be built was overrun by Soviet forces. While it did not reach operational status, the work was briefly continued by the Soviet Mikoyan-Gurevich (MiG) design bureau as the Mikoyan-Gurevich I-270.



Active combat operations began in May 1944, although on a small scale. As expected, the aircraft was extremely fast; and for a time, the Allied fighters were at a complete loss as what to do about it. Singly or in pairs, the Komets attacked, often faster than the opposing fighters could dive in an attempt to intercept them. A typical Me 163 tactic was to zoom through the bomber formations at 9,000 m (30,000 ft), rise up to an altitude of 10,700–12,000 m (35,100–39,000 ft), then dive through the formation again. This approach afforded the pilot two brief chances to fire a few rounds from his cannons before gliding back to his airfield. The pilots reported that it was possible to make four passes on a bomber, but only if it was flying alone.


As the cockpit was unpressurized, the operational ceiling was limited by what the pilot could endure for several minutes while breathing oxygen from a mask, without losing consciousness. Pilots underwent altitude-chamber training to harden them against the rigors of operating in the thin air of the stratosphere without a pressure suit. Special low-fiber diets were prepared for pilots, as gas in the gastrointestinal tract would expand rapidly during ascent.


More than three years passed before Major Wolfgang Späte could form the first Me 163 combat wing, (Jagdgeschwader 400 (JG 400) ), in Brandis near Leipzig, which followed the establishment of the Erprobungskommando 16 Me 163B-dedicated test and evaluation unit at Peenemunde-West eleven months earlier. JG 400's purpose was to provide additional protection for the Leuna synthetic gasoline works which were raided particularly heavily and frequently at the end of 1944. A further group was stationed at Stargard near Stettin to protect the large synthetic plant at Pölitz (today Police, Poland). Further defensive units of rocket fighters were planned for Berlin, the Ruhr and the German Bight.


The first actions involving the Me 163 occurred at the end of July, when two USAAF B-17 Flying Fortress were attacked without confirmed kills. Combat operations continued from May 1944 to spring 1945. During this time, there were nine confirmed kills with 14 Me 163s lost. Feldwebel Siegfried Schubert was the most successful pilot, with three bombers to his credit.


Allied fighter pilots soon noted the short duration of the powered flight. They would wait, and when the engine died they would pounce on the unpowered Komet. However, the Komet was extremely manoeuvrable and could pull out of a turn much later than any Allied fighter. Another Allied method was to attack the fields the Komets operated from, and strafed them after the Me 163s landed. Establishing a defensive perimeter with anti-aircraft guns ensured that Allied fighters avoided these bases. 


At the end of 1944, 91 aircraft had been delivered to JG 400 but a continuous lack of fuel had kept most of them grounded. It was clear that the original plan for a huge network of Me 163 bases was never going to happen. Up to that point, JG 400 had lost merely six aircraft due to the enemy actions. Nine were lost to other causes, remarkably low for such a revolutionary and technically advanced aircraft. In those last days of the Third Reich the Me 163 was given up in favour of the more successful and threatening Me 262. In May 1945, Me 163 operations were stopped, the JG 400 disbanded, and many of their pilots sent to fly Me 262s.


In any operational sense, the Komet was a failure. Although they shot down 16 aircraft, mainly expensive four-engined bombers, that did not warrant the efforts put into the project. With the projected Me 263, things could have turned out differently, but the Komet was an ineffective fighter aircraft. Due to fuel shortages late in the war, few went into combat, and it took an experienced pilot with excellent shooting skills to achieve "kills" with the Me 163.
The Komet was a remarkable design that pointed the way to the future. It was one more piece of evidence that the day of the propeller fighter was over, and it also spawned later weapons like the Bachem Ba 349 Natter and Convair XF-92. Ultimately, the point defense role that the Me 163 played would be taken over by the surface-to-air missile (SAM), Messerschmitt's own example being the Enzian. The airframe designer, Alexander Martin Lippisch went on to design delta-winged supersonic aircraft for the Convair Corporation.


Source: Wikipedia