History Of The Lambda-4S Rocket

Hideo Itokawa

The story of the Japanese space program starts with Hideo Itokawa (糸川 英夫). Mr. Itokawa was born in Tokyo July 20th, 1912. As a young child he seemed fascinated with flight (Matogawa, 2007). When Itokawa was 14 years old Charles Lindbergh made the first nonstop solo flight across the Atlantic. Itokawa was disappointed of the news, dreaming of being the first himself. Not too easily discouraged he made up his mind to be the first to cross the Pacific instead. (He did not, this was accomplished by Clyde Pangborn in 1931).

Nevertheless he enrolled in the School of Aeronautical Science at the University of Tokyo in 1932. He graduated in 1935 writing his dissertation on the problem of the sound barrier (2010, p. 3). By the 30’s Japan was brandishing imperial power in the Pacific, having already started invading Northeast China (Manchuria). Itokawa applied to the officer corps of the Imperial Japanese Army, but was turned down due to poor health. Instead, under advice of a professor he joined the Nakajima Aircraft Company (中島飛行機株式会社). While less famous in the West than Mitsubishi, Nakajima designed and built many aircraft for Japan during World War II. Itokawa and Yasuni Kayama led the development of the Ki-43 Hayabusa (隼, Japanese word for a falcon) — A single engine fighter manufactured by the thousands.

After the war American occupied Japan was forbidden from building aircraft or rockets^{[citation needed]}. In need of work Itokawa, age 33, took a position in the medical school at the University of Tokyo. In 1949 he completed a doctoral thesis on the acoustic qualities of the flute and violin (furthering the field of computational acoustic modeling). Afterwards he developed a tool for measuring levels of anesthesia and in 1953 he was invited to the United States as a guest lecturer for 6 months at the University of Chicago.

This trip was a turning point for Itokawa. While vising the US he saw the rapid progress the nascent American space program was making. When he returned to the University of Tokyo he talked to the director of the Institute of Industrial Science Shouji Hoshiai about building rockets in Japan. Still thinking about trans-pacific flight he published a pop-science article in the Japanese daily newspaper Mainichi-Shimbun on high altitude flight with rockets.^{[citation needed]}

The Beginning Of Japanese Rocketry

By 1952 Japan was once again a sovereign nation free to pursue research in aerospace. What was missing was money. Post-war Japan was impoverished and still recovering from having been fire-bombed into ruble by the United States. Itokawa went around to many industry friends trying to build up support for his ideas.

AVSA

Itokawa also attracted attention from young researchers at the Institute of Industrial Science. He wrote up an ambitious plan describing a hypersonic, high altitude rocket-plane that could transport people across the Pacific Ocean in only 20 minutes. After a provisional meeting in December 1953 (Matogawa, n.d.) a research group named “Avionics and Supersonic Aerodynamics” (AVSA¹) was formed to pursue this idea.

However Japan had not kept up with aerospace research around the world during post-war reconstruction and occupation. In order to get a grasp on supersonic rocket flight, they decided they needed to test some rockets.

Despite the difficult economic situation, AVSA was able to claw together about $140,000 (in 2016 USD) in various donations and government issued matching industry grants. That was all they had for the first year of work, materials, and 40 people!

As luck would have it they found a friend who worked with explosives during the war and had a stash of leftover double-base propellent meant for firing projectiles, rocket-propelled grenades and the like. Despite each propellent grain being only about 12 cm long Itokawa was immediately excited. He realized that launching something—anything—was worth doing so they could get started.

The smaller, the better. We have little money. If the propellant is small, we can burn many of them. The first task is to study how rockets fly. If the test rocket is small, we can test-fly easily. Let's launch small rockets as frequently as possible. These tiny fuels are just we have been looking for.

— Hideo Itokawa   

(Matogawa, 2007)

Propellent in hand, they set out to built a test program.

The Pencil Rocket

Again hampered by a lack of anything resembling a proper testing facility, the group came up a very clever way to make meaningful test flights. The tiny pencil rockets were fired horizontally through a test of evenly spaced paper screens. Very thin wires were also run through the screen, and hooked up to an oscilloscope. As the rocket flew it would break the wires and leave an impression in the paper screen. After the flight the speed and acceleration was measured from the oscilloscope and the exact rotation rate was worked out by looking at the difference in radial position of the fin marks in each paper screen.

Thus, with a few dollars and a concrete bunker AVSA was able to successfully test and create predictions of the effects of fin size, shape, mass distribution, nose cone shape, etc. They had an empirical description of rocket flight.

The International Geophysical Year

Very soon after AVSA got to work thinking about rocket-planes, the International Geophysical Year (IGY) started to build up momentum. In many ways the IGY is what started the space race. Both the US and USSR, as well as many countries with nascent space programs (or hopes to start one) joined in pledging to do high-atmosphere and space research throughout 1957.

At first Japan was asked to build instruments that could possibly be flown on US sounding rockets, but they hesitated. The Japanese delegate to the IGY meetings was curious if Japan could participate with an entirely indigenous space program, instead of being an extra to the United States.

Itokawa was persuaded (apparently without much trouble) to commit to flying an experiment to space (over 100 km) by 1958 (within 3 years). Thus AVSA at the Institute of Industrial Science at the University of Tokyo, under the lead of Itokawa, fully committed to being Japan’s space program.

From Pencil to Baby

Soon after firing dozens of Pencil rockets in the horizontal test bay, they started to launch them in open air, out over the ocean. But they were too small to place any instruments or radios in, and too small to see easily and tracked. It was still helpful to work out the logistics of a launch site.

Itokawa started working on a larger rocket, named Baby.

Bigger and Higher: Kappa

The Lambda Program

Timeline

— 1912 Itokawa born

— 1927 Lindbergh crosses Atlantic

— 1931 Japan invades Manchuria

— 1932 Itokawa enrolls in university

— 1937 Japan invades China

— 1939 Itokawa joins Nakajima Aircraft

— 1945 End of WWII

— 1945 Itokawa joins the Todai medical school

— 1952 End American occupation of Japan

— 1953 Itokawa spends 6 months in US

— 1953 First meeting of AVSA

— 1955 April - First Pencil launch