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B R E A KT H R O U G H S T H AT D I D N ’ T
Turbine-Powered Cars
If it’s the jet age, why doesn’t a car have a jet engine? After a decade or so of work, Chrysler released the Turbine Car in the Sixties, building five prototypes and 50 vehicles for the public to test. The technology worked and offered advantages in durability and maintenance, but the car was noisy, relatively slow, and poor on fuel economy. By the Eighties, Chrysler permanently grounded the idea of a jet-powered car.
C U TAWAY
THE FIRST MAINSTREAM automatic transmission, the General Motors Hydra-Matic, is easily one of GM’s greatest contributions to autodom. Using simple mechanics, complicated math, and incredible production standards, the company introduced a technology that would not be fully mastered until decades after its 1939 debut. These days automatic transmissions equip about 99 percent of new vehicles sold in the U.S., a dominance achieved thanks to undeniable advantages. Compared with any manual transmission, today’s automatics are easier to use, as reliable, and often faster and more fuel efficient. This ease changed the world. By making cars almost effortless to drive, GM spawned the large American cruisers that reshaped our highways and enabled rampant suburbanization. Some feared the Hydra-Matic was too complicated a machine to ever be reliable. It proved its durability, though. When World War II paused all consumer automotive production in the U.S., Cadillac put Hydra-Matic transmissions into M-5 light tanks—helpful for the war effort and later for the postwar marketing folks. Confidence in the Hydra-Matic soared. The breakthrough autobox stayed in production for decades and cemented the automatic transmission as a must-have option for almost all consumer cars.
A. The input shaft connects to the engine, turning even when the brakes are holding the car. Manual transmissions solve this by requiring the driver to engage the clutch, but the technology to automate this process in a reliable, compact consumer product did not exist. Without something to mediate the relationship between input and output gears, a car would stall at every stop. B. The Hydra-Matic solved the stall issue with a simple fluid coupling. Rather than rotating a fixed gear shaft, the input rotates a container of fluid. This fluid transfers torque onto the output shaft but, importantly, can also simply spin around if the output shaft is locked in place. Later automatics added a stator that multiplies torque output. Those designs became known as torque converters.
F
AUTOMATIC FOR THE PEOPLE GM’S HYDRA-MATIC
IS REVOLUTIONARY, CONFOUNDINGLY COMPLICATED, AND RUGGED ENOUGH FOR WAR.
