The throaty roar, the staccato drumming, the grinding growl, the clatter and popping - all are sounds reminiscent of bygone days in aviation, when the engine was every bit as exciting as the airplane it powered. These sounds of yesteryear, except in a few rare instances where the aircraft and engine are preserved and operated, are merely fond memories.

No finer example of engineering can be found then is exhibited by aircraft engines. They contain nothing that it does not require, and every single part must have a long service life and return the maximum possible output of power for its weight.

Reliability has always been of greatest importance and the aircraft engine of today can run almost indefinitely. Even in the "golden age" of aviation it had remarkable reliability for transoceanic flights and endurance attempts. The power to weight ratio was steadily improved as was the proportionate rate of fuel consumption. The radial engine achieved a tremendously favorable power to weight ratio, but at the expense of frontal area. Consequently, cowling had to be provided to streamline and force cooling, but it eliminated the weight of liquid cooled systems along with their problems.

The elimination of liquid cooled systems improved dependability of aircraft engines, particularly single row radials, and the double row radials that appeared in the middle thirties. Their dependability on long distance flights is legend.

Please visit [The Aviation History] On-Line Museum for a peek inside a radial engine after you browse here.