Charlie Fehn’s invention was submitted to at least 3 U.S. military tests for evaluation for use as a NTV (Narrow Trail Vehicle) in South East Asia. I found records of 5 such tests running from November of 1960 to June of 1963. If the information that Jim Cavanaugh gave me is correct then this bike was used in 2 of these tests. He said there was one West bend powered bike built before Nethercutt switched to the JLO powered MK1s.
I have complete copies of RAVE I and RAVE II, Swamp Fox I and the Swamp Fox II Volume III report. RAVE stands for Remote Area Vehicle Evaluation. Best I can figure RAVE I was part of Swamp Fox II. Swamp Fox II testing covered a lot more than just vehicles. There are 10 volumes that include medical and aircraft evaluation. They were testing in Panama to simulate conditions in Southeast Asia.