https://creativecommons.org/publicdomain/zero/1.0/https://www.rawpixel.com/image/4026307
Grumman.
The Ag-Cat design goes back to 1955 when Grumman designers Joe Lippert and Arthur Koch put forward a proposal for a new agricultural aircraft.
At this time, Grumman was heavily involved in building military aircraft, particularly for the US Navy, so the idea of building an agricultural aircraft was novel. Lippert and Koch saw a need for a strong aircraft for crop dusting and spraying as there were no good purpose-built aircraft and the accident rate with surplus WWII trainers adapted for ag work (such as the Boeing Stearman) was high. The two designers asked the industry what they wanted and then proceeded to build the aircraft around a 220 horsepower Continental engine. These war surplus engines could be bought for just $25.00 each!. Original public domain image from Flickr
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