Rearwin Aircraft began developing the Cloudster in 1938, while still selling the older Speedster and Sportster. The goal was to develop an aircraft with side-by-side seating, using as much tooling and existing equipment as possible. Widening either the Speedster or Sportster was considered, but by the time the design was completed, the strut geometry, landing gear, fuselage structure, engine installation, and cabin had to be changed. Development of the prototype took 6 months. Originally the plane was dubbed the "Rearwin Coupe," a name which changed to "Cloudster" after a month. The 90hp prototype was never developed for production, instead the basic Model 8125 used a 120hp Ken-Royce 7F engine also made by Rearwin. In 1940, the Model 8135 added a third, sideways-facing, seat to the Model 8125. Pan American Airways founder Juan Trippe, who personally owned a Rearwin Sportster, approached the company in 1941 to develop an instrument trainer. The existing Model 8135 was redesigned and certified in four months as the 8135T. Pan Am bought 5 of the design, while another 20 went to various operators.
Design
The Cloudster was a two- or three-seat aircraft of high-wing design and conventional landing gear arrangement. Designed to seat two side-by-side, the Model 8135 introduced a third seat behind the front row which could be accessed by folding the right-hand seat forward. The last model, Model 8135T, sat two in tandem. All versions used Ken-Royce radial engines of 90-120hp, as the engines were produced by a division of the Rearwin Aircraft & Engines Company and the company was experienced building airplanes with small radial engines. Beginning in late 1941, the Cloudster used a NACA cowling hinged along the top for engine access. The interior of the Cloudster used surplus cloth from Cadillac and a simulated woodgrain panel. A baggage compartment held 50lbs. The tandem seating Model 8135T introduced jettisonable doors for both the instructor and student pilot, dual controls, and seats with removable cushions to accommodate backpack or seat parachutes. The student sat in the rear seat with their own controls and a removable instrument panel. The 8135T included fittings for a blackout curtain surrounding the student for instrument training, while allowing the instructor to maintain normal visibility.
Operational history
In 1941, 25 Model 8125 Cloudsters were exported to the Aero Club of Iran. The aircraft remained in service as of 1945, with a.30 caliber machine gun mounted on the left wing strut outside the propeller arc. From August 1941 to July 1942, 25 Model 8135T trainers were sold to various operators. How long they served is unknown.
