The Kari-Keen 90 Sioux coupe was designed by Swen Swanson and is a two-seat side by side high-wing monoplane with conventional landing gear. The wing is fully cantilevered, with skylights built in. The fuel tank sits above the pilot’s head and is part of the leading edge. Ole Fahlin built all the propellers and test flew the aircraft.
Production of the Sioux coupe began in 1929. The first model, the Kari-Keen 60 Sioux Coup, featured a 60 hp (45 kW) Veile M-5 engine. 22 aircraft were built without a type certificate.
In 1930, six more model 90s were built with a type certificate. The price was US$3,365 in 1930.
In 1931, the Sioux Aircraft Corporation bought the company assets, changing the name of the Kari-Keen 90 into the Sioux Coupe 90.
One 1930 Coupe 60 (ATC 2-81), powered by a 65hp Velie M-5 engine, was carried over from Kari-Keen inventory to Sioux Aircraft Corporation.
With the re-organization of Kari-Keen Aircraft Co, the 1931 Sioux Coupe 90 was a slight variation of the Kari-Keen 90. Designed by Swen Swanson and redesign by Gazley & LaSha, the one built, NC10544, sold for $3,355. Originally powered by a 90hp Brownback Tiger, it was later re-powered with a 110hp Warner Scarab.
The Sioux Coupe 90-B Junior (ATC 414) built in 1931, NC10721, sold for $3,500. Originally powered by a 90hp Warner engine, there are reports that a 90hp Lambert was also installed at one time.
The Sioux Coupe 90-C Senior (ATC 2-356) NC10735 was built in 1931.
Production of the Sioux coupe ended on 1 August 1933.
Variants:
Kari-Keen 60 Sioux coupe
First flight 1929. 22 built
Sioux Coupe 90
Lambert R-266 radial engine 90hp.
First flight 1930. 6 built
Sioux Coupe 90A
powered with a 90 hp Brownback Tiger
First flight 1933. 1 built
Sioux Coupe 90B Junior
powered with a 90 hp Warner Scarab Junior – One built
First flight 1931.
Sioux Coupe 90C Senior
powered with a 110 hp Warner Scarab – One built
First flight 1931.
Specifications:
Kari-Keen 90-C Sioux coupe
Engine: 1 × Warner Scarab Radial, 110 hp (82 kW)
Propeller: 2-bladed Ole Fahlin
Wing area: 150 sq ft (14 m2)
Airfoil: Eieffel 385
Gross weight: 1,580 lb (717 kg)
Fuel capacity: 25 US gallons (95 l; 21 imp gal)
Cruise speed: 66 kn; 122 km/h (76 mph)
Crew: one
Capacity: one passenger
Sioux Coupe 90
Engine: 90hp Brownback Tiger
Wingspan: 30’0″
Length: 23’0″
Useful load: 533 lb
Max speed: 115 mph
Cruise: 100 mph
Stall: 45 mph
Range: 400 mi
Seats: 2
Sioux Coupe 90-A
Engine: 90hp Brownback Tiger, later 110hp Warner Scarab
Wingspan: 30’0″
Length: 23’0″
Useful load: 533 lb
Max speed: 115 mph
Cruise: 100 mph
Stall: 45 mph
Range: 400 mi
Seats: 2
Sioux Coupe 90-B Junior
Engine: 90hp Warner
Wingspan: 30’0″
Length: 23’0″
Useful load: 530 lb
Max speed: 115 mph
Cruise: 98 mph
Stall: 45 mph
Range: 400 mi
Seats: 2
Sioux Coupe 90-C Senior
Engine: 110hp Warner Scarab
Wingspan: 30’0″
Length: 23’3″
Seats: 2
All Aero 