G-164A Super Ag-Cat - One 335kW (450hp) Pratt & Whitney R-985 series nine cylinder radial piston engine, driving a two blade constant speed propeller.
G-164B Ag-Cat Super B Turbine - Choice of 373kW (500shp) Pratt & Whitney Canada PT6A-11AG, or 510kW (680shp) PT6A-15AG, or 560kW (750shp) PT6A-34AG turboprops, driving a three blade constant speed prop.
G-164A - Max speed 237km/h (128kt), typical working speed range 130 to 160km/h (70 to 86kt). Initial rate of climb 1080ft/min.
Super B Turbine with PT6A-15AG - Working speed 210km/h (113kt). Range with max fuel 318km (172nm).
G-164A - Empty equipped for spraying 1220kg (2690lb), max certificated takeoff 2040kg (4500lb).
Super B Turbine - Empty equipped for spraying 1429kg (3150lb), max takeoff 3184kg (7020lb).
Usually pilot only. Hopper capacity 1514 litres (400US gal/333Imp gal). Some converted with a second cockpit for joyflights.
Schweizer built 2628 under contract for Grumman between 1959 and 1979, including more than 400 G-164s, 1330 G-164As and 832 G-164Bs. Also built under licence in Ethiopia.
Biplane agricultural aircraft
The Ag-Cat is one of the most successful purpose designed agricultural aircraft yet built and has been in almost continuous production since 1959.
Grumman developed the G-164 Ag-Cat biplane in the mid 1950s, with the prototype making its maiden flight on May 27 1957. Some 400 initial G-164 Ag-Cats were delivered from 1959, with an open cockpit, and fitted with a variety of 165-335kW (220-450hp) radial engines including the 165kW (220hp) Continental W-670-6N, the 180kW (240hp) Gulf Coast W-670-240, the 185kW (245hp) Jacobs L4, or 205 or 225kW (275 or 300hp) Jacobs engines.
The G-164A followed. In its basic A/450 form it was powered by a 335kW (450hp) Pratt & Whitney R-985, and featured a greater maximum takeoff weight and additional fuel. The A/600 is similar other than its 450kW (600hp) R-1340 engine. The G-164B/450 is based on the A/450 but with increased span wings, while the B/525 is powered by a 390kW (525hp) Continental/Page R-975.
The longer fuselage 450kW (600hp) R-1340 powered G-164C/600 meanwhile forms the basis for the Pratt & Whitney Canada PT6A powered Turbo Ag-Cat D.
Recent models include the 450kW (600hp) R-1340 powered Ag-Cat Super B/600 and the PT6A powered Ag-Cat Super B Turbine (various PT6A models are offered ranging from 375 to 560kW (680 to 750shp).
After the two prototypes, Grumman subcontracted Schweizer to build all the Ag-Cats for them. After Grumman American was formed in 1973, responsibility for the Ag-Cat was transferred to the new company. In 1978 the company was renamed Gulfstream American. In January 1981 Schweizer bought the design and marketing rights, and was now solely responsible for the Ag-Cat program. In 1995 Schweizer sold the Ag-Cat's manufacturing rights to the Ag-Cat Corp of Malden, Missouri who have built a small number of aircraft. Ethiopian Airlines has built 11 G-164B Ag-Cat Super B Turbines under licence as the Eshet, powered by Pratt & Whitney PT6A-34AG turbines.
Many conversions are or were available for the Ag-Cat:
Agri-Jet Power Turbo-Cat with a 430kW (575shp) Garrett TPE-331 turbine.
Clark Lycoming-Cat with a 300kW (400hp) horizontally opposed Lycoming piston engine.
Frakes Turbo-Cat with a 560kW (750shp) P&W PT6A-34 or 403kW (540shp) PT6A-34AG turbine.
Harker Leo-Cat with a 418kW (560hp) British Alvis Leonides radial engine.
Marsh Turbo-Cat with a 450kW (600shp) Garrett TPE-331-1-101 turbine.
Malden Ag-Craft with two seats for training.
Mid-Continent King-Cat with a 895kW (1200hp) Wright R-1820 Cyclone radial.
Page Ag-Cat with a 450kW (600shp) Lycoming LTP-101 turbine.
Serv-Aero Leo-Cat with a 418kW (560hp) British Alvis Leonides radial engine.
Stage II Ag-Cat with a 485kW (650hp) Stage II Chrysler V-8 piston engine.
Turbines Turbo-Cat with a PT6 turbine.
Twin-Cat Corp Twin-Cat with two 230kW (310hp) horizontally opposed Lycoming TIO-540-J engines.
Others were converted for airshow flying, like Gene Soucy's Show Cat, and Joe Kittinger's Rosie O'Grady's Flying Circus display team, or are used for banner towing, firefighting, or pleasure flying.