Retaining the same basic airframe of the preceding CH-200 and CH-300, the CH-400 was fitted with a more powerful Pratt & Whitney Wasp radial engine.

Two were used for radio research, and one as an air ambulance for the U.S. Marine Corps.

The aircraft was also available in a deluxe version for private pilot owners, fitted with a more powerful Wasp variant providing 450 hp (336 kW) and detail enhancements.

Two of these aircraft were purchased by the government of the Dominion of Newfoundland in 1937, and one later ended in private hands.

Data from American airplane specifications[1]General characteristics Performance