In 1944, Gilbert Trimmer, building on his Trimmer Trimcraft project, developed a design for the Allied Aviation Corporation of Baltimore, Maryland. This design was for a lightweight, three-seat amphibian aircraft, reminiscent of a scaled-down Grumman Goose.
The following year, the production license was sold to Commonwealth Aircraft Inc., a reorganized entity of Rearwin Co., based in Kansas City, Kansas.
Design and Production
In 1947, two examples of the Commonwealth C-170 Trimmer (NX41853, NC41999) were built. These were three-seat, cantilever high-wing aircraft. They were equipped with two 85 hp Continental C-85 piston engines driving two-bladed propellers. Auxiliary floats were also installed on each wing.
Commercialization and Fate
The aircraft were offered for sale at a price of $5975 USD. However, no orders were received, and the company ceased operations in 1949.
The first amphibian prototype flew during 1947. Sadly, the second example was destroyed during static testing.
Technical Specifications
| Modification | C-170 |
| Wingspan, m | 10.82 |
| Length, m | 7.57 |
| Height, m | 2.62 |
| Wing area, m2 | 15.10 |
| Empty weight | 667 |
| Maximum takeoff weight | 998 |
| Engine type | 2 Continental C-85 Piston engines |
| Power, hp | 2 x 85 |
| Maximum speed, km/h | 212 |
| Cruising speed, km/h | 185 |
| Practical range, km | 966 |
| Rate of climb, m/min | 268 |
| Service ceiling, m | 4267 |
| Crew, crew | 3 |
Image and diagram gallery of the Commonwealth C-170 Trimmer
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