The Airplane - Jay Spenser [102]
The Lockheed P-38 Lightning was one of many U.S. World War II airplanes equipped with exhaust-driven turbo-superchargers.
Museum of Flight, Seattle
By then, aero propulsion had become so excruciatingly complex that keeping it all going had turned into a frustrating exercise in diminishing returns. Propulsion technologies that had reached their zenith in World War II were pushed too far in the 1950s, leading to a precipitous decline in engine and propeller reliability levels.
Fortunately, help was on the way.
The great clipper ships of the latter 1800s were the fastest commercial sailing vessels of all time. Rakish and slender, with five or six courses of sail on high masts, these global greyhounds transported tea, spices, and other high-value cargoes at two or even three times the speed of conventional sailing ships. Flying fully rigged before the trade winds, their speed approached 20 knots (23 mph or 37 km/h).
The United States led in the design and construction of clipper ships, which often returned to New York from China with their precious loads of perishable tea in under a hundred days. Because the season’s first cargoes commanded exorbitant prices, there was a great incentive to go fast. However, this capability came at a high cost because clipper ships pushed existing sailing technology to its limit. Carrying so much sail, they were more complex and expensive to operate than other vessels. They needed large crews and worked them very hard. Worse still, they required a great deal of maintenance and, being highly prone to damage, were in constant need of repair. It was with an audible sigh of relief that maritime operators switched over to steel-hulled steamships in the late nineteenth century.
That technological transition parallels the one that commercial aviation undertook as the 1950s came to a close. Airlines too heaved a relieved sigh when switching from piston airliners to jetliners. But just as something grand was lost when tall ships became an anachronism, so too did aviation forever lose a degree of romance with the disappearance of the propeller.
The jet age dawned because a soft-spoken German youth found science more interesting than the military career planned for him. Growing up in Dessau, near Leipzig, Hans Pabst von Ohain successfully convinced his father to let him attend Göttingen University.
Philosophical by nature and manifestly brilliant, young von Ohain completed that world-leading institution’s seven-year doctoral program in just four years, receiving a doctorate in physics with minors in aerodynamics, aeromechanics, and mathematics in November 1935.
Long interested in flight, von Ohain took up gliding in school but dropped the sport soon afterward when it was politicized by the National Socialist regime, which came to power in 1933. But that brief taste of gliding set von Ohain thinking, particularly the contrast it struck with a commercial flight he had taken from Köln (Cologne) to Berlin. So clangorously noisy and beset with vibrations was that early airliner that it started him wondering whether there might be a better way to power airplanes.
What sprang to mind at Göttingen was the gas turbine engine, a concept then being batted around in academic settings. There were good reasons why such jet engines did not yet exist. One was the difficulty of achieving sustained operation, which demanded a theoretical understanding and deft control of high-speed airflows. Another was the challenge of locally extreme temperatures that would push the limits of existing metallurgical knowledge.
Dr. Hans von Ohain.
National Air and Space Museum, Smithsonian Institution
From the lectures of Dr. Ludwig Prandtl, von Ohain knew that airplanes would someday operate at very high speeds. Certain that turbine