A Century of Imagination



HE-178, the world’s first jet-propelled aircraft to fly.

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After the 75th anniversary of the flight of the first jet aircraft, powered by an engine his father designed, LEAD Cincinnati CIO Awards honoree Chris von Ohain reflects on his father’s remarkable achievements in the field of jet propulsion.

 

A midmorning haze clung to the ground near Germany’s Baltic coast August 27, 1939. German physicist Dr. Hans von Ohain, 28, listened anxiously for a susurration from the He S 3 jet engine he’d designed. 

There it was, the He 178 aircraft powered by the He S 3 engine, a murmur and a distant blot on the horizon. The world’s first gas-propelled plane approached and landed to a jubilant crowd of spectators. 

For von Ohain, the successful flight validated his enormous undertaking, the years-long labor of designing the He S 3’s propulsion system. But the flight was also a signal of things to come, of his importance to the future of aviation. 

“He was a technical genius,” says Chris von Ohain of his father, who passed away in 1988, 75 years removed from that test flight. “The idea of a jet came to him when he was flying as a college student in the early 1930s. He said it was loud and vibrated like hell. He imagined it should be more smooth and elegant.”

“It wasn’t as romantic as I thought it would be,” said Hans in a 1981 interview, referring to that same flight. He remembered his 20-year-old self had expected flying to be smooth and, save the tingling hum of the engine, satisfyingly quiet. The experience of flying in a plane, no less than the equations of physics that enabled it, should have been deeply elegant. But “the propellers made a horrendous noise. The airplane rattled because it had piston engines. The elegance of flying was totally taken away by the shaking, vibrating, noisy stinking reciprocating machine.”

Hans was born December 14, 1911 in Dessau, Germany. The son of a professional military officer-turned-businessman, von Ohain’s childhood was pleasurable, a halcyon span that no doubt impacted his adult life by supplying him with both memories of past peacefulness and the requisite ambition to think he could reclaim them in the present.

"When I examine myself and the methods of my thought,” Einstein famously said, “I come to the conclusion that the gift for imagination has meant more to me than any talent for abstract thought.”

The quote had a lasting impact on von Ohain, both when he heard it in youth and afterwards as he toiled on jet propulsion. It typified a philosophy that urged practitioners of science to think beyond the supposedly air-tight laws of nature that had been accepted for centuries. The age that followed was one of creativity, intuition and invention – an age quite as intoxicating as those of the industrial and computer revolutions. 

In the spirit of this age, von Ohain was exhorted as a Ph.D. student at the University of Göttingen to imagine new fields of possibility. Indeed, possibility was the magic word, as Einstein's own quantum discoveries had inaugurated – to Einstein's own dismay – the eventual dismemberment of the Newtonian model. Individual subjectivity, comprising the perceived attributes of the world around us and heavily depending upon space, time, cause and effect, was diminished in favor of a physical reality that eluded our senses but was nevertheless supported by experiments. 

Von Ohain was enthralled by this reevaluation of Newton’s laws, even if in his field the laws were not so comprehensively overturned. He took special interest in thermodynamics, which had created maps of fluidic systems Newton's laws could observe but not fully explain. 

“Jet propulsion was the applied mechanics of Newton only much more sophisticated,” von Ohain said. “Newton’s ideas of how lift and drag occur were wrong.” 

At Göttingen, the young physicist learned how they actually occured – how differences in pressure and acceleration could create a circulating thermodynamic system around an airfoil or turbine blade. After earning his doctorate in physics in 1935, he started to conceive of something that would make use of these phenomena. 

“My thoughts began to focus on a steady state aerodynamic flow process in which the energy for compressing the fresh air would be extracted from the combustion gas without machinery,” explained von Ohain. “I intended to accomplish this process without employing moving machinery by bringing the inflowing fresh air in direct contact with the expanding combustion gas.”

The first experimental concept was considerably less productive than this intention. Nevertheless, Ernst Heinkel, a forward-looking entrepreneur and owner of one of the top airframe manufacturers in Germany, was persuaded. He hired von Ohain in early 1936 to design a fully working gas turbine engine.

The eventual outcome of von Ohain’s efforts was the He S 3, a gas propulsion device with back-to-back radial compressors and a radial inflow turbine. Though the design was far simpler than what exists in aircrafts today, the processes are similar: a centrifugal compressor and stator system compresses inflowing air, the air is mixed with fuel and ignited, then released through a turbine and nozzle. The resulting force propels the aircraft forward and lift is generated through the cambered airfoil design of the wings. 

The He S 3 was put inside the He 178 jet airplane. August 27, 1937 the screaming engine lifted the aircraft above the midmorning fog to circle 500 miles over the Baltic Sea at altitudes of 3,000 feet. The crowd was elated with the flight of the first gas-propelled jet engine.  

But the leaders of Reich Air Ministry were not. Whether this is a happy or sad fact of history, we'll never know. Five days later, Hitler’s armies marched into Poland and all interest in the jet propulsion engine was suffocated by the war.