Grumman G-164 Ag-Cat

Display Status:

This object is on display in the Boeing Aviation Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.

Collection Item Summary:

The Grumman G-164 Ag-Cat is the first aircraft specifically designed by a major aircraft company for agricultural aviation, the aerial application of chemical, fertilizer and seed, and it is one of the most successful with nearly 2,700 built. After consulting with agricultural pilots, Grumman introduced the Ag-Cat in 1957. The Ag-Cat handles the rigors of very low altitude, high "g force" agricultural application maneuvers with rugged construction, a low stall speed and good visibility.

This Grumman G-164 Ag-Cat, N332Y (serial number 207), rolled off the factory line on May 2, 1963, and, in 1974, became a G-164A Super Ag-Cat, with the change to a 600 hp engine and a 300 gallon hopper. Although it has 12,778 flight hours applying seed, fertilizer, pesticides and herbicides to nearly any crop grown in the United States, all chemical residues have been removed. In 2008, many radial and turbine powered Ag-Cats are still in use.

Collection Item Long Description:

The Grumman G-164 Ag-Cat is the first aircraft specifically designed by a major aircraft company for agricultural aviation and is one of the most successful as well. Following World War II, agricultural aviation (aerial chemical, fertilizer and seed application) rapidly expanded with the growth of food production for the post-war domestic and export markets. The Grumman Aircraft Company saw the need for a special purpose "duster" design and, after consulting with agricultural pilots and companies around the country, introduced the Ag-Cat in 1957. In 2008, piston and turbine powered Ag-Cats are still performing this critical and dangerous duty.

Dusting crops with insect-control chemicals began in the south in the early 1920s as a tool to combat the cotton industry's boll weevil nemesis. The venerable war surplus WWI Curtiss JN-4D Jenny was put into service, but it soon became apparent that a more "purpose designed" crop duster was needed. The Huff-Daland Manufacturing Company of Ogdensburg, New York modified its Petrel 5 military/commercial biplane into a practical duster with a chemical tank and spreader system and formed the Huff-Daland Duster Company in Louisiana. C.E. Woolman soon took over the faltering company and with entomologist Dr. Bert Coad built a pioneering insect and chemical research and aerial delivery business throughout the country. Woolman also expanded the business to include passenger and freight carrying and renamed it Delta Air Service, which became Delta Airlines. With the deep Depression years of the 1930s and then World War II, further development of crop duster airplanes was shelved until after the war. Delta Airlines later restored one of the only two remaining original Huff-Daland Dusters and donated it to the Smithsonian's National Air Museum in 1968; it now hangs at the Steven F. Udvar-Hazy Center near this Grumman G-164.

After World War II, surplus Stearman military biplane trainers were pressed into duster service to fulfill the urgent need, many of them structurally reinforced and equipped with surplus Pratt and Whitney 450 hp radial engines to handle the rigors of the very low altitude, high "g force" crop dusting maneuvers. The Stearman was a good airplane; however, it and other civil aircraft such as the DC-6 and Antonov AN-2M were never designed for sustained flying in this type of environment. Crop dusting is flying swaths of fields at extremely low altitude (8-10 feet), performing procedural turns at low altitude, and climbing and diving expediently for position and to avoid wires and trees. The field of flight must be exact to ensure precise, even application and contain drift of the load only onto the field and not onto homes or roads. Power management, maneuverability, and changing weight and balance combined with wind drift and specific application characteristics of the load add to the ever-changing equation for the pilot. Consequently a number of airplane companies began to consider an airplane design to meet these specific requirements.

In 1955, Grumman preliminary design engineers Joe Lippert and Arthur Koch proposed the design for a "purpose built" crop dusting airplane as a means of fulfilling a pressing need by the agricultural community as well as the perceived need for Grumman to diversify its product lines. A major consideration for their rugged and maneuverable biplane duster concept was the availability of thousands of inexpensive war surplus 220 horsepower Continental radial engines. The aircraft structure would have to be very strong to accommodate the large hopper, payload, and accompanying spray/spreader equipment and sustain safe flight. For expediency, prototype construction began at Lippert's home as Roy Grumman approved their plan for experimental test prototypes in 1956 and also provided a hanger and a limited number of personnel and funding for building and testing at Bethpage, Long Island.

The Ag-Cat's first flight, made on May 27, 1957, went exceedingly well with the second prototype following one month later. Three senior crop dusting pilots were brought in from various parts of the country to test the airplane and, in the summer of 1958, an extended east coast demonstration tour allowed well over 100 duster pilots to put the two prototypes through their paces. The pilots were delighted with its handling qualities and its low stall speed of 67 mph as stalling an aircraft, i.e. loss of lift, while entering a turn at low speed and low altitude was a major crop duster pitfall. Pilots were also impressed with the cockpit that offered good visibility and was designed to withstand a 40 g impact. One of the pilots, Dick Reade, suggested the name "Ag-Cat" in keeping with Grumman's practice of using the word "cat" in its military aircraft nomenclature, i.e. Hellcat; Reade's name is painted on this NASM aircraft.


Upon their return to Bethpage, Lippert and his team found that an upsurge of Grumman military orders were going to prevent the production of the Ag-Cat at the Long Island factory, however, the Board of Directors subcontracted the entire program to the Schweizer Aircraft Company of Elmira, New York. The first Schweizer-built Ag-Cat flew in 1959. The Ag-Cat is a single-seat, strut-braced biplane with a 35 percent wing stagger which provides the excellent low speed wing stall characteristics that are necessary for low altitude maneuvers. The fuselage is constructed of a welded steel tubing truss which is covered with removable aluminum panels to facilitate post flight cleaning. The pilot's safety reinforced open cockpit is protected with a headrest mounted turnover structure and the 33 or 40 cubic foot cargo bin (217 gallons or 1,200 pounds) is located in front of the pilot over the airplane's center of gravity. The non-retractable fixed landing gear is of the conventional steerable tailwheel type with cantilever spring steel main landing gear legs. The wings are constructed of aluminum with two spars and are covered with a combination of aluminum sheet and fabric. All four outer wing panels are identical to make them interchangeable in the field. This feature also substantially reduces the spares inventory required. The tail unit structure is of the braced steel tube type and is fabric covered. The original G-164 came with engines ranging from 220 hp to 300 hp and was then upgraded to engines of 300 hp to 600 hp (164A Super Ag-Cat) with a hopper capacity of 247 gallons or 2,000 pounds.

Schweizer built a total of 2,646 Ag-Cats; 1,730 were 164s and 164As for Grumman between 1959 and 1980. Schweizer purchased the certificate from Gulfstream (formerly Grumman) and, beginning in 1981, introduced subsequent models with engine options and longer wings and fuselages to accommodate larger hoppers and their payloads: the Super-B 600, Super-B PT6 turbine, and the PT6A Turbo Ag-Cat D with a 500 gallon hopper. Ag-Cat Corp bought the certificate in 1995 and built about 5 aircraft; then Allied Ag-Cat purchased the design but did not build any aircraft. Ethiopia Air Lines built 15 Super-B turbines in the 1990s Many radial and turbine conversions continue to power this rugged aircraft and have substantially lengthened the life of this great design.

Two well known air show pilots have flown the Ag-Cats for years--Gene Soucy and his Show Cat and Joe Kittinger at his Rosie O'Grady Flying Circus show. While most Ag-Cats remain in the commercial agricultural business, some are flown for firefighting and banner towing, and a few are privately owned.

This Grumman G-164 Ag-Cat, N332Y and serial number 207, rolled off the factory line on May 2, 1963, as one of the early license-built production models by Schweizer. The first test and acceptance flight was conducted on May 6, 1963 and at the time of manufacture it was equipped with a 300 hp Jacobs R-755A2M1 engine and a Sensenich propeller. In late May 1963, the airplane was ferried to a company leasing operation in Oxnard, California. In late 1963, the wings were covered with .040 sheet aluminum. It was registered to Shell Aviation on April 11, 1974 and in November 1974 the airplane was upgraded to Super Ag-Cat standards with the installation of a 300 gallon cargo hopper and a 600 horse power Pratt & Whitney R-1340 engine. Moe's Crop Dusting Service purchased the airplane in 1975 and installed special booster wing tips on all four wing panels. HBR Aviation Leasing purchased the plane in the late 1970's. On May 1, 1982, the airplane was involved in a ground accident when it struck a ground trailer. HBR installed a locking tail wheel in 1985 and, in March 1987, replaced the metal covered wings with fabric covered ones and installed under wing spray booms as well as a speed ring cowling on the R-1340 radial engine. Ralph Holsclaw of Growers Air Service in Woodland, California, purchased the Ag-Cat from HBR Aviation Leasing on November 29, 1993.

As a crop duster this aircraft accumulated 12,778 flight hours applying seed, fertilizer, pesticides and herbicides to nearly any crop that is grown in the United States. The airplane was struck from the records on September 30, 1999 when the engine was removed from the airplane (later replaced for the Museum).

In 2004 the National Agricultural Aviation Association contacted the National Air and Space Museum regarding the potential addition of modern crop duster aircraft to the collection and learned that the Museum was indeed searching for an appropriate agricultural aircraft. The NAAA alerted the agricultural aviation community and organizations, and in August 2005, Ralph Holsclaw and Growers Air Service offered to donate their Grumman G-164A Super Ag-Cat. Growers delivered the Ag-Cat, completely cleaned of all chemical residues and restored, to the Museum's Garber Facility in March 2008.