Jets bring in new era of air power

Spokesman Magazine, Jan, 2004 by Gary Null

On August 27, 1939, German Captain Erich Warsitz lifted off the runway at the Heinkel factory in Marienehe, Germany. What was unusual about this flight is that it was the first flight of a jet-powered aircraft.

Captain Warsitz was piloting a Heinkel 178 powered by a jet engine developed by Dr. Hans Van Ohain. With this flight, Germany became the first country to fly an operational jet aircraft.

Interestingly, Dr. Von Ohain was not the first to develop a jet engine. That honor goes to Sir Frank Whittle of England. The son of a mechanic, Frank was interested in both engines and flying from an early age. As soon as he was old enough he joined the Royal Air Force as an apprentice. Unfortunately, this position did not allow him to fly.

Mr. Whittle excelled in his assignment and also worked with the Model Aircraft Society where he built replicas. His work impressed his commanding officer, who also thought that Mr. Whittle was a mathematical genius. He was so impressed that he recommended Apprentice Mr. Whittle for the Officer Training College at Cranwell. Mr. Whittle was not from the "public school" class of society and generally only about one percent of candidates from the Apprentices made it through the course. Mr. Whittle became one of few who made it. Part of his motivation was that the course did include flying lessons and he became an accomplished pilot.

Another requirement of the school was that each student had to produce a thesis. Mr. Whittle decided to write his thesis on future developments in aircraft design. Propeller planes of the day were quite unsatisfactory to someone with Mr. Whittle's mechanical background. They were noisy, vibrated a lot, slow, and the engines were prone to breakdown while requiring highly refined fuel.

His solution was to create an engine that worked on the same principle that drove a party balloon. When the air in the inflated balloon is allowed to escape, it drives the balloon about through the force of the exhaust. Mr. Whittle's plan was for an engine with but one moving part. This was a shaft, which had compressor blades on one end and turbine blades on the other. Air coming in the front would be compressed to about four times the pressure of the atmosphere and then mixed with vaporized fuel. This would then be ignited and the resulting blast would exit through the rear of the engine, providing thrust and spinning the turbine to power the compressor blades. It would also run on kerosene. Perhaps what is most interesting was that Mr. Whittle was 21 years old at the time his thesis was published in 1928.

Mr. Whittle worked on perfecting his design and finally patented it in 1930. He also submitted his idea to the Air Ministry, where it was looked at by one of its top scientists, A.A. Griffith. Griffith's response was to point out an error in Mr. Whittle's calculations, which resulted in Mr. Whittle receiving a letter from the Air Ministry telling him that they were not interested in his idea. He was an outstanding pilot, however, and the RAF decided that he really needed a university degree. So he was sent to Cambridge University to get one. Work on his engine was delayed by this interlude.

In Germany a young student named Hans Von Ohain obtained his degree in Physics from the University of Gottingen. He later obtained a position as the junior assistant to Hugo Von Pohl, the director of the Physical Institute at the University. Meanwhile, the German government under the Nazi control, wanted to rebuild their air force and several aircraft manufacturers were working to achieve this goal. One major manufacturer, Ernst Heinkel, came to the university asking for new propulsion designs. Director Von Pohl recommended his star pupil, Hans Von Ohain.

Dr. Von Ohain had independently conceived the idea of a "continuous cycle combustion engine" in 1933. He worked on the design and in 1934 patented a jet propulsion engine design which was similar to Mr. Whittle's in concept, but had a different internal arrangement. This intrigued Heinkel and he hired Dr. Von Ohain, who came to work for him in 1936. By September of the following year Von Ohain performed a successful bench test of his engine design.

This resulted in Mr. Heinkel setting his designers to work on an aircraft to be powered by the new engine. The result was the Heinkel 178, which flew three years after Heinkel hired Dr. Von Ohain. So while the British built the jet engine first, it was the Germans who first put one in an aircraft and created an operational jet plane.

In Italy another engineer was at work. Secondo Campini graduated from his university in 1929 and began studying the concept of jet propulsion. He determined it was feasible and published his opinion in an Italian aviation journal. He also sent a report to the Italian Air Ministry recommending jet propulsion. In 1931 he founded a jet aircraft and water-craft company known by its Italian initials, V.E.N.A.R.

The Air Ministry responded to his recommendations by awarding him a contract in 1935 to build two aircraft and one fuselage for static tests. Campini's company did not have the manufacturing capability to produce the aircraft, so he joined up with the Caproni company, who were building aircraft for some time. Together they produced an aircraft. Unfortunately they were also trendsetters in production delays and cost overruns, much to the dismay of the Air Ministry. Eventually the fuselage for the static engine test was completed and functional. Production of the two aircraft then proceeded.