11/30/2013. Remarks by Walter van Tilborg: "The Model J was a product of the Bendix Helicopter, Inc. (subsidiary of the Aviation Division of the Bendix Corporation and founded in 1943 as Helicopters, Inc., before becoming Bendix Helicopters, Inc. in 1944). The Model J was again a design of Martin Jensen and a prototype was first flown on September 15, 1946 and alike the smaller Model K, it was fitted with contra-rotating rotors mounted above each other.
The Model J was powered by a 450 hp Pratt & Whitney R985-B4 radial engine. The design was in 1946 offered to the USN, but not taken up and reportedly the original plans called for the construction of up to 6 examples of the Model J, but must likely only the two prototypes (NX74101 c/n 1 and NX74102 c/n 2) were completed.
When Bendix quit the helicopter business the assets (and certainly NX74101) were acquired by Gyrodyne of America, Inc. and further development then resulted in the GCA-2."