The Tatra 77 is generally considered to be the first production aerodynamically-designed automobile. Paul Jaray, the Zeppelin aerodynamic engineer with knowledge and access to Zeppelin manufacturer JZ’s wind tunnel, and Hans Ledwinka, who was able to take that knowledge and incorporate it into an advanced luxury sedan’s design made this leap possible.. Moving away from Tatra’s trademark tubular chassis, the 77 was coach built on a platform chassis with a pressed box-section steel backbone. The 60 horsepower rear-mounted 2.97-litre V8 engine was air-cooled and upgraded to a 75 horsepower 3.4-litre engine for the 77A. Advanced features for a 1934 vehicle include overhead valves, hemispherical combustion chambers, dry sump, fully independent suspension, rear swing axles and extensive use of lightweight magnesium alloy for the engine, transmission, suspension and body. With modest horsepower in a large sedan, the drag coefficients of 0.2455 for the 77 and 0.212 for the Tatra 77A allowed a top speed of over 150 km/h (93 mph).
