The Flying Keys

Fred and Al Key were brothers who performed barnstorming events and other activities during the early 20th century. They are best known for their flight endurance record, which they cemented at twenty-seven days. They also invented a valve for aerial refueling that became the industry standard for the United States military.

Brothers Fred and Al Key became interested in aviation after World War I. They started doing some barnstorming in the 1920s and continued their interest as the managers of the Meridian Municipal Airport, in Meridian, Mississippi.

With the onset of the Great Depression, the city of Meridian began doing whatever it could to save money. The airport was considered unnecessary, given the economic conditions, and was slated to be closed.

The Key brothers had no desire to see this happen, so they came up with a plan to draw attention to Meridian and its airport by breaking the standing flight endurance record of 23 days. At that time, air-to-air refueling was a dangerous affair. If gasoline was spilled, which often happened, it could be ignited by the hot engine exhaust.

To solve this problem, the Key brothers, along with local inventor and mechanic A. D. Hunter, invented a spill-free fueling system that consisted of a valve on the end of the fuel nozzle which was opened by a probe in the neck of the fuel tank. The valve would not allow fuel to flow unless it was inserted into the fuel tank. During fueling, if the nozzle was removed from the tank, the fuel would automatically stop flowing. This nozzle was later adopted by the US Army Air Corps, and is still in use today with some modifications.

Refueling the plane wasn't their only concern. The engine needed regular maintenance during the flight in order to stay in good running order. To facilitate this, a catwalk was built so that Fred could walk out and work on the plane while it was airborne.

On June 4, 1935, The Flying Keys, as the brothers later became known, lifted off in a borrowed Curtiss Robin monoplane named Ole Miss from Meridian, Mississippi's airport. For the next twenty-seven days, they flew over the Meridian vicinity. Several times each day, the crew of a similar plane would lower food and supplies to the brothers on the end of a rope, as well as supply fuel via a long flexible tube. They landed on July 1 after traveling an estimated 52,320 miles and used more than 6,000 gallons of gasoline.

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