WORLD WAR 2 IN REVIEW: A Brief History of Guided Missiles in World War II

The idea of guided missiles was born during World War I. The use of the airplane as a military weapon brought about considerable thought concerning a remotely controlled aircraft which could be used to bomb a target. The leaders in the field were Orville Wright, who flew the first airplane; E. A. Sperry of the Sperry Gyroscope Company; and Charles F. Kettering of General Motors Corporation. It was these men who devised and tested our first missile, the “Bug,” a small version of the aircraft used in those days. While the first missile did not get into combat, a most important result of these early tests was the recommendation that any future work should be done with radio-controlled aircraft so that the missile could be given necessary adjustments while in flight.

In 1924, funds were allocated for developing a missile using radio control. Numerous, moderately successful flights were made during the 1920s with radio control. By 1932, however, the project had been listed in the files under frills and luxuries and closed because of lack of funds.

About 1935, two brothers named Good, amateur model airplane builders, built and flew a model plane that was remotely controlled by radio waves transmitted from the ground. These flights were the first completely radio-controlled flights on record.

Radio-controlled target planes were the first airborne remote-controlled aircraft used by the U.S. Army and Navy.

By December of 1941 just before the United States’ entry into World War II, remote-controlled aircraft were developed to the point where they were seriously considered for use as a weapon of warfare by Gen. Arnold, then Chief of Staff of the Army Air Corps.

So far we have discussed only the missile powered by internal combustion engines and propellers. Work also was done to develop missiles using the reaction-type engines, including rocket engines, which contain within themselves all the elements needed for power, and jet engines, which depend on the surrounding atmosphere as a source of oxygen. When a nuclear powerplant for aircraft is developed, both the jet and rocket engines may become obsolete insofar as missile powerplants are concerned. Let’s now look at the progress that rocketry has made in the United States.

Development of American Rocketry

Dr. Robert H. Goddard, at one time a physics professor at Clark University, Worcester, Massachusetts, was largely responsible for the sudden interest in rockets back in the 1920s. When Dr. Goddard first started his experiments with rockets, no related technical information was available. He started a new science, industry, and field of engineering. Through his scientific experiments, he pointed the way to the development of rockets as we know them today. The Smithsonian Institute agreed to finance his experiments in 1920. From these experiments he wrote a paper titled A Method of Reaching Extreme Altitudes, in which he outlined a space rocket of the step (multi-stage) principle, theoretically capable of reaching the moon.

Goddard discovered that with a properly shaped, smooth, tapered nozzle he could increase the ejection velocity eight times with the same weight of fuel. This would not only drive a rocket eight times faster, but sixty-four times farther, according to his theory. Early in his experiments he found that solid propellant rockets would not give him the high power or the duration of power needed for a dependable supersonic motor capable of extreme altitudes. On 16 March 1926, after many trials, Dr. Goddard successfully fired, for the first time in history, a liquid propellant rocket into the air. It attained an altitude of 184 feet and a speed of 60 miles per hour. This seems small as compared to present-day speeds and heights of missile flights, but instead of trying to achieve speed or altitude at this time, Dr. Goddard was trying to develop a dependable rocket motor.

Dr. Goddard later was the first to fire a rocket that reached a speed faster than the speed of sound. He was first to develop a gyroscopic steering apparatus for rockets. He was the first to use vanes in the jet stream for rocket stabilization during the initial phase of a rocket flight. And he was first to patent the idea of step rockets. After proving on paper and in actual test that a rocket can travel in a vacuum, he developed the mathematical theory of rocket propulsion and rocket flight, including basic designs for long-range rockets. All of this information was available before World War II, but evidently its immediate use did not seem applicable. Near the end of World War II the U.S. started intense work on rocket-powered guided missiles, using the experiments and developments of Dr. Goddard and the American Rocket Society.

The American Rocket Society was developing rockets and rocket motors after its organization in 1930. Its first motor was based mostly on German designs obtained from the German Rocket Society in 1931. The American Rocket Society was first to build a sectional rocket motor that could test motors of different sizes and shapes, thus cutting down the cost of a new motor for each type tested.

In 1941 some members of the American Rocket Society formed a company known as Reaction Motors, Inc. It was organized to develop and manufacture rocket motors for both military and civilian use.

Development of German Rockets

The first flight of a liquid propellant rocket in Europe occurred in Germany on 14 March 1931, five years after Dr. Goddard made his first successful rocket test. A German scientist named Johannes Winkler was in charge. Winkler lost his life a short time later during one of his experiments.

Germany by this time had begun to sense the future importance of liquid propellant rockets in warfare. In 1932 Gen. Walter Dornberger (then a captain) of the German Army obtained the necessary approval to develop liquid propellant rockets for war purposes. By 1936, Germany decided to make research and development of guided missiles a major project. Germany spent $40,000,000 on a project, known as the Peenemünde Project, for establishing a large rocket research and development laboratory. Hitler put the members of the German Rocket Society to work there, closing to the rest of the world German developments on rockets until after the war. Unlike Germany, the U.S.A. during this time paid little attention to the development of jet and rocket propulsion for any specific purpose.

Evolution of Jet Engines

The rocket was just one type of jet propulsion powerplants that was being proposed and worked on in this century. As early as 1913, Rene Lorin, a French engineer, proposed and first patented the idea for a ramjet powerplant. Lorin’s patent was followed by a Hungarian patent for a similar device in 1928 and another French patent in 1933. None of the proposed ideas resulted in a workable engine. The failures occurred not because the fundamentals of operating such a device were not known but because technical information on high-speed fluid flow was unavailable. A period of thirty-two years separated Lorin’s original idea and the first free-flight testing of a ramjet powered vehicle capable of developing thrust in excess of drag. This test occurred in June 1945 when the Applied Physics Laboratory of Johns Hopkins University successfully flew the first ramjet powered aircraft.

The forerunner of the present day turbojet was not a thermaljet but a mechanical type. In 1927, the Italian Air Ministry began investigating the possibility of propelling an aircraft by placing a conventional propeller inside the mouth of a venturi-shaped fuselage. This so-called “ducted propeller” installation was a form of mechanical jet propulsion. Tests with this “ducted propeller” installation demonstrated that it possessed excellent maneuverability and stability characteristics, although its overall performance was only mediocre. In 1932, an Italian by the name of Campini designed and later flew an aircraft propelled by a thermaljet engine. His jet-powered aircraft was not, however, a turbojet, because it depended upon a conventional reciprocating engine instead of a gas turbine for compressor power.

Evaluation of Campini’s engine had hardly been made when improved jet engines began to appear in various countries. A young British engineer and Royal Air Force officer, Frank Whittle, had filed a patent for a thermaljet engine as early as 1930. Whittle’s design eliminated the reciprocating engine as the power source for driving the compressor. Instead, the mixture of air and gases was used after combustion to drive a gas turbine. The turbine drove the compressor. On 7 April 1941, a Gloster “Pioneer” aircraft, powered by Whittle’s engine, became airborne during taxiing tests and flew about 150 yards at an altitude of about six feet. On 15 May 1941, this same aircraft made the first official takeoff for a turbojet powered aircraft and flew for 17 minutes.

After these successful flights, the Army Air Corps sent a special group of men to England to study the engine. Further development became a British-American project. At this time, only ten hours of jet engine operation had been accumulated in fifteen flights.

Turbojet development in the U.S. was turned over to the General Electric Company because of its experience in the development and production of turbo-superchargers. Today, turbojet engines are built and developed by nearly all aircraft engine companies.

Another air-jet engine is the pulsejet. This type of engine was patented by a German engineer in 1930, but a good, workable pulsejet engine was not perfected until World War II. It became famous during the war as the powerplant of the German “buzz bomb” or V-1. This engine was capable of propelling the V-1 at 450 miles per hour.

In 1940, General Motors Corporation was given a contract to build and develop jet-powered, controllable bombs which in the final version were to be command-controlled with television. These bombs were tested extensively in 1941 and 1942. The testing led to the development of new types of jet-powered bombs.

Enemy Guided Missiles of World War II

The Japanese were far behind the Germans in developing missiles during World War II. The “Baka,” used by the Japanese during the war was not a guided missile in the true sense of the word. It was a rocket-propelled, piloted glide bomb designed for use against shipping targets. The “Baka” was known as a suicide bomb. Although it achieved a certain degree of success, it had poor maneuverability, a characteristic which resulted in many of them being shot down by anti-aircraft fire.

The Japanese also tried an air-launched, radio-controlled, rocket-assisted glide bomb. This missile had to be dropped from a low altitude, and the control plane had to get within 2½ miles of the target. The procedure made the control plane an easy target for anti-aircraft fire. The project was dropped before the end of the war.

The German developments in the field of guided missiles during World War II were the most advanced. Their most widely known missiles were the V-1 and V-2 surface-to-surface missiles. As early as the spring of 1942, the original V-1 had been developed and flight tested at Peenemünde. In 1943, Germany was working on forty-eight different anti-aircraft missiles. These were later consolidated into twelve projects for immediate development into useful weapons. Toward the end of the war, all efforts were being directed toward the successful production of an anti-aircraft missile capable of intercepting Allied bombers.

The V-1 (a robot bomb) was a pilotless, pulse-jet, mid-wing monoplane, lacking ailerons but using conventional airframe and tail construction. All guidance and control was accomplished internally by gyro stabilization and preset compass guidance. It was launched from a ramp 150 feet long and 16 feet above the ground at the highest end. A speed of approximately 200 miles per hour had to be reached before the V-1 propulsion unit could maintain the missile in flight. The missile carried a warhead weighing 1,988 pounds.

The V-1 (vengeance weapon #1) was not accurate, and it was susceptible to destruction by anti-aircraft fire and aircraft. However, the interruptions it caused in the functioning of a vital war center such as London, together with the amount of physical damage it did, made the V-1 effective in lowering morale.

The V-2 (vengeance weapon #2) was the first long-range, rocket-propelled missile to be put into combat. Concentrated efforts began in 1941. The V-2 was put into mass production, and the first V-2 landed in England in September 1944.

The V-2 was a supersonic missile, vertically launched and automatically tilted to a 41 to 47 degree angle a short time after launching. The maximum range was about 200 miles, and the top speed was about 3,300 miles per hour. The V-2 was a large missile, having a length of 46 feet 11 inches and a diameter of 5 feet 5 inches. Its total weight at takeoff was over 14 tons, including a 1,650-pound war-head.

Active countermeasures against the V-2 were impossible. Except for its initial programmed turn, it operated as a free projectile at extremely high velocity.

Five other German missiles were also highly developed during World War II and were in various stages of test.

One of these, the “Rheinbote,” was also a surface-to-surface missile. This rocket was a three-stage device with booster-assisted takeoff. Its range was about 135 miles, with the third stage reaching over 3,200 miles per hour in about 25 seconds after launching. Overall length of the rocket was about 37 feet; but after having dropped a rearward section at the end of both the first and second stages, it had a length of only 13 feet. The 13-foot section of the third stage carried an 88-pound high-explosive warhead.

A surface-to-air missile, the “Wasserfall,” was a radio-controlled supersonic rocket, similar to the V-2 in general principles of operation. Fully loaded it had a weight of slightly less than 4 tons. Its length was 25 feet. Designed for intercepting aircraft, this missile had specifications which called for maximum altitude of 65,000 feet, speed of 560 miles per hour, and range of 30 miles. Its 200-pound warhead could be detonated by radio after the missile had been command-controlled to its target by radio signals. It also was to use an infrared proximity fuze and homing device for control on final approach to the target and for detonating the warhead at the most advantageous point in the approach. Propulsion was to be obtained from a liquid propellant powerplant, with nitrogen-pressurized tanks.

Another surface-to-air missile, the “Schmetterling” (HS-117), was still in the development stage at the close of the war. All-metal in construction, it was 13 feet long and had a wing span of 6½ feet. Effective range against low-altitude targets was 10 miles. It traveled at 540 miles per hour at altitudes up to 35,000 feet. It was to use a proximity fuze to set off its 55-pound warhead. Propulsion was obtained from a liquid propellant rocket motor with additional help from two booster rockets during takeoff. Launching was to be accomplished from a platform which could be inclined and rotated toward the target.

A third German surface-to-air missile was the “Enzian,” designed to carry payloads of explosives up to 1,000 pounds. It was to be used against heavy bomber formations. The “Enzian” was about 12 feet long. It had a wing span of approximately 14 feet and weighed a little over 2 tons fully loaded. Propelled by a liquid propellant rocket, it was assisted during takeoff by four solid propellant rocket boosters. Launching, as in the case of the “Schmetterling,” was from a rotatable launcher, with range elevation possible. Its range was about 16 miles, speed 560 miles per hour, and maximum altitude 48,000 feet. Guidance was by command control. It was believed to be gyroscopically stabilized in roll.

A German air-to-air missile, the “X-4,” was designed to be launched from fighter aircraft as shown in the illustration. Propelled by a liquid propellant rocket, it was stabilized by four fins placed symmetrically. Length was about 6½ feet and span about 2½ feet. Its range was slightly over 1½ miles, and its speed was 560 miles per hour at an altitude of 21,000 feet. Guidance was accomplished by electrical impulses transmitted through a pair of fine wires from the fighter aircraft. The wires unrolled from two coils mounted on the tips of two opposite fins of the missile. This missile was claimed to have been flown, but it was never used in combat.

United States Guided Missiles of World War II

A project for developing missiles in the U.S.A. during World War II was instigated in 1941. In that year the Army Air Corps asked the National Defense Research Committee to undertake a project for the development of a vertical, controllable bomb. The committee initiated a glide-bomb program which resulted in standardization of a preset glide bomb attached to a 2,000-pound demolition bomb. The “Azon,” a vertical bomb controlled in azimuth only, went on the production line in 1943. Project RAZON, a bomb controlled in both azimuth and range, was started in 1942 but not completed until the end of the war. A medium-angle glide bomb called the “ROC” and a 12,000-pound bomb known as the “Tarzon,” both controllable in azimuth and range, were also under development at this time. The two bombs did not reach the combat stage during World War II. The “Tarzon” project was dropped in 1946 and picked up again in 1948. The “Tarzon” was used successfully in the Korean action.

In 1943, a project was initiated for development of a glide torpedo. Standard Navy torpedoes were used for this project. In the final days of the war, these glide torpedoes were used on several missions in the Pacific theater.

In 1944, the U.S. carried out a glide-bomb mission against Cologne, Germany. A majority of the bombs reached the target area. In this same year remote television-control equipment was developed and installed in bombing aircraft. These aircraft were used to control television-sighted, explosive-laden bombers unfit for further service. These radio-controlled bombers saw some service over Germany under the “Weary Willie” project. Light and radar target-seeking devices were developed for use with glide bombs and were tested until 1945.

Our first jet-propelled missile was actually a flying-wing, jet-powered, and radio-controlled bomb. The second version of a jet-propelled bomb was a copy of the German V-1 with a few improvements. Another model consisted of a combination of the two mentioned above, using the flying wing together with the pulse-jet engine of the V-1. This project became obsolete in 1946. By 1946 the “Tiamat,” a guided aircraft rocket, had been completed to the extent that full-size versions were being tested.

The Navy had a number of guided missile projects under development by the end of the war. One of these, the “Gargoyle,” was an air-launched, powered, radio-controlled glide bomb with a flare for visual tracking. The Navy also had a glide bomb called the “Glomb.” It was guided to a target by radio control, monitored by television. The “Loon,” a modification of the German V-1, was to be used from ship-to-shore and to test guided missile components. Another missile, known as “Gorgon IIC,” used a ramjet engine with radar tracking and radio control.

During the war, these weapons were developed under pressure for immediate use. At the end of the war in 1945, nearly all previous development on guided missiles, controllable bombs, and guided aircraft rockets was considered obsolete. New military characteristics and specifications were drawn up with future weapon possibilities in mind.

Japanese Ohka ("Baka").

Henschel Hs 117 Schmetterling.

Ruhrstahl X-4 air-to-air missile.

Rheinbote.

Henschel Hs 117 Schmetterling.

Wasserfall surface to air missile, launched from Peenemünde, 23 September 1944.

Enzian surface-to-air missile mounted on a Flak 8.8cm gun chassis. The Enzian (named for a genus of mountain flower, in English the Gentian) was a German World War II surface-to-air anti-aircraft missile that was the first to use a radio controlled guidance system. During the missile's development in the late stages of the war it was plagued by organizational problems and was cancelled before becoming operational.

Rheinmetall Borsig Rheinbote on launcher.

Rheinmetall Borsig Rheinbote on launcher ready for transport.

Northrop P-61C Black Widow night fighter used for tests of the U.S. Navy Gorgon IV missile (designated KUM-1, PTV-2, and PTV-N-2). The U.S. Navy began the Gorgon IV program in May 1945. The missile, contracted to Martin, was originally planned to be a ramjet-powered air-to-surface missile with an active radar seeker. The program was terminated in April 1949. The P-61C carries its USAAF serial 43-8336. Due to the style of the U.S. national insignia, the picture was taken before 1947. The U.S. Marine Corps acquired 12 P-61As in 1946 as trainers, which were designated F2T-1 and carries U.S. Navy serials (BuNos 52750-52761).

Enzian E-4 (production) surface to air missile (also could be used as air-to-air missile).

AZON, the first smart bomb developed by the United States.

The Henschel Hs 117 Schmetterling (German for Butterfly) was a radio-guided German surface-to-air missile project developed during World War II. There was also an air-to-air version, the Hs 117H.