09/30/2014. Remarks by Walter van Tilborg and Johan Visschedijk: "The Mini 500 light single-seat helicopter was derived from the Cicaré CH-6 of the Argentinean designer Augusto Cicaré. The open structure prototype CH-6 (X-101) was present at the 1990 EAA Oshkosh convention and was flown during the show by Dennis L. Fetters. It was the intention to market the CH-6 in the USA, albeit with a fully enclosed composite material fuselage and single tail boom and the configuration resembled a scaled-down Hughes 500, hence Mini 500. Fetters founded Revolution Helicopters Corporation at Excelsior Springs, Missouri, but since no agreement was reached on the use of the patented control system of the CH-6, the Mini 500 received an own design control system.
The prototype (N500ZZ) was built by Dennis Fetters and his Revolution Helicopters Corporation and made its first flight during the Spring of 1992. Deliveries of kits started late-1994/early-1995 and the standard (recommended) powerplant was the 64 hp Rotax 582 two-stroke engine. The Mini 500 soon became a very popular design for amateur aircraft builders.
The refined Mini 500 Bravo (or Mini 500B) was announced in 1997 and used the same engine, but had a upgraded rotor head and transmission, as well as technical improvements to the tail rotor and airframe. Externally it was similar to the baseline Mini 500.
The Turbine Mini 500 designation was used for aircraft which were re-engined with a small (115 to 200 shp) turbine engine developed by Rinke Aerospace Corporation. The first turbine engine Mini 500 was the aircraft of Joe Rinke and was flown in 1995. Several further Mini 500s were later re-engined with Rinke turbines, resulting in an improved overall performance. At least one Mini 500 was completed (or re-engined) in the USA with a Solar T62 turbine.
In October 1999 Revolution Helicopters ceased operations and reports at the time suggested the company`s activities would be continued by Mid-American Helicopters. However, these plans were shelved and instead Millennium Helicopter, LLC continued the development and introduced an upgraded airframe and a new powerplant. The upgraded version was re-designated as MH-1 and became available on the market early-2010 with initially an 100 hp Rotax 912 or 115 hp Rotax 914. Improvements included a new rotor with longer and foldable blades, a new rotor mast, modified fuselage construction and modernized equipment and systems. Mid-2011 trials started with an engine based on the Yamaha Genesis 120 snowmobile engine.
At least 500 kits of the Mini 500 were sold of which some 250 appeared on the FAA register (completed or non-completed) and dozens in other countries and up to 100 may have flown.
During a test flight on June 25, 1992, N500ZZ was substantially damaged when it crashed in Missouri City, Missouri, caused by an improper connecting rod assembly and subsequent sudden power loss. Three years later (on July 27, 1995) the aircraft was again substantially damaged in a crash at the EAA Convention at Oshkosh, Wisconsin, when it experienced a total loss of power after re-jetting the carburettor to achieve proper main rotor rpm and exhaust gas temperature readings. The registration N500ZZ was cancelled from the FAA register on September 20, 2013."