Convection oven

The convection oven emerged because troops crossing the Atlantic during World War II needed hot meals instead of cold emergency rations—and an inventor who had already built robot navigators for aircraft turned to solving the food problem.

William L. Maxson ran the W.L. Maxson Corporation, which produced various inventions during World War II including robot navigators for air pilots and mechanical calculators. In 1944, he began working on a way to serve proper meals to military personnel on long flights. Cold rations were the only option, and morale suffered.

Maxson's insight was simple but revolutionary: install a fan in the back of an oven to force hot air around the food. Traditional ovens rely on natural convection—hot air rises, cold air sinks, creating uneven heating. Forced convection moved air continuously past the food, cooking it faster and more evenly.

In 1945, Maxson filed his patent and produced the Whirlwind Oven. Built from aluminum and steel, it weighed 35 pounds and operated on a 120-volt DC motor, readily available in military aircraft. The oven could heat frozen meals in half the time of conventional ovens. Maxson also developed segmented aluminum trays to hold the meals—the ancestor of the TV dinner.

The combination of frozen meals and convection heating created the first airline food service for the U.S. Air Force. Meals weren't gourmet, but they were vastly better than cold rations. The Whirlwind Oven could only reach about 200 degrees Fahrenheit, and its popularity declined by the late 1940s when microwave technology emerged.

But the forced convection principle survived. In the 1960s, the Malleable Iron Range Company engineered the first full-size convection oven for home use. The technology continued evolving until 2010, when Philips introduced the Airfryer, using rapid air circulation to simulate deep-frying without oil—a direct descendant of Maxson's wartime innovation.