Revolution Mini-500

{{Short description|American kit helicopter}} {{Use mdy dates|date=March 2023}} {{Use American English|date=March 2023}}  {{Infobox aircraft | name = Mini-500 | logo = | logo_size = | image = Mini 500.jpg | alt = | caption = A Mini 500 hands-off demonstration | long_caption = | other_names = | aircraft_type = Single-seat light [[helicopter]] | aim = | outcome = | related = | national_origin = [[United States]] | manufacturer = [[Revolution Helicopter Corporation]] | design_group = | designer = | builder = | issuer = | status = Kit production completed November 1999 | owners = | primary_user = | more_users = | service = | major_applications = | proposals = | prototypes = | number_built = 500 kits, about 100 completed and flown<ref name="Sweeney" /> | construction_number = | civil_registration = | military_serial = | radio_code = | requirement = | aircraft_carried = | flights = | total_hours = | total_distance = | construction_date = | introduction = 1994 | retired = | first_flight = 1992 | initiated = | in_service = | last_flight = | expected = | developed_from = | variants = [[Millennium MH-1]] | developed_into = | preservation = | fate = | predecessors = | successors = | concluded = }} The '''Revolution Mini-500''' is a 1990s [[United States|American]] single-seat light [[helicopter]], designed and built by [[Revolution Helicopter Corporation]] as a kit for [[Homebuilt aircraft|homebuilding]].<ref name="Brassey" />

Revolution Helicopter went out of business in November 1999 and kits are no longer available.<ref name="Sweeney" /><ref name="WDLA04">Bertrand, Noel; Rene Coulon; et al: ''World Directory of Leisure Aviation 2003-04'', page 214. Pagefast Ltd, Lancaster OK, 2003. ISSN 1368-485X</ref>

==Development== [[File:VH-BJC Revolution Mini-500 (8543313461).jpg|thumb|right|Revolution Mini-500, tail section view]] The Mini-500 was designed as a light helicopter that resembles a scaled-down [[MD Helicopters MD 500|Hughes 500]], powered by a [[Rotax 582]] {{convert|64|hp|kW|0|abbr=on}} [[two-stroke engine]].<ref name="Brassey" />

The Mini-500 design was initially based upon [[Augusto Cicaré]]'s control system design as incorporated in his CH-6 prototype helicopter, but company president Dennis Fetters and Cicaré were unable to agree on licensing terms. Fetters instead elected to design and patent a "newly improved control system".<ref name="Armstrong">Armstrong, Kenneth: ''Choosing Your Homebuilt — the one you will finish and fly! Second Edition'', page 202-205. Butterfield Press, 1993. {{ISBN|0-932579-26-4}}</ref>

The Mini-500 has a tubular steel [[fuselage]] with a foam and glass-fibre structure cabin. It has a two-bladed semi-rigid rotor and a conventional two-blade [[tail rotor]]. The first Mini-500 flew in 1992 and the company delivered the first production factory-assembled helicopter in July 1994. Production of kits ceased in 1999 and the company claimed that more than 500 had been sold.<ref name="Sweeney">{{cite web|url = http://www.generalaviationnews.com/editorial/articledetail.lasso?-token.key=1495&-token.src=news&-nothing |title = Revolution Helicopter folds|accessdate = 2009-07-11|last = Sweeney|first = Michael|date=November 1999 |archive-url = https://web.archive.org/web/20070310164032/http://www.generalaviationnews.com/editorial/articledetail.lasso?-token.key=1495&-token.src=news&-nothing |archive-date = 2007-03-10}}</ref><ref name="Brassey" />

The factory advertised the kits, saying: "no machining, welding or cutting is required and the package includes pre-drilled guide holes for easy alignment during construction ... pre-fabricated, lightweight superstructure with all complicated components pre-assembled at the factory, ''i.e.'', upper main transmission/reduction with rotor head, instrumentation panel, and tail rotor gear box assembly)." Also included in the kit were the composite cabin structure, doors, transmission cover and [[Tailplane|horizontal stabilizer]].<ref name="Armstrong" />

The initial kit price was [[United States dollar|US$]]24,500 and included the Rotax 582 powerplant, fiberglass enclosure, basic instrumentation, electric starter, [[landing lights]] and navigation lights. The components came pre-painted in a variety of optional colors. The composite tail and main rotor blades were advertised as “lifetime on condition", indicating no fixed lifespan. Assembly time was advertised as 40 hours.<ref name="Armstrong" />

After Revolution Helicopter ceased operations, there was an attempt in 2003 led by Richard Stitt and [[Stitt Industries, Inc.]] to restart production of the Mini-500. The company started providing replacement engines to existing Mini-500 owners to replace the under-powered [[Rotax 582]]s and intended to produce new Mini-500s. Initial intentions were that it would be powered by a [[Mazda]] [[Wankel engine]], but this was abandoned and plans shifted to the [[Solar T62]] turbine engine. There is no indication that Stitt delivered any aircraft kits.<ref name="WDLA04" />

==Operational use== [[File:VH-BJC Revolution Mini-500 (8544408662).jpg|thumb|right|Revolution Mini-500]] It is unclear how many Mini-500s have been built, with the company claiming to have sold over 500 Mini-500s kits with more than 400 built and flown, it has also been claimed by critics that no more than 100 have been actually built and flown.<ref name="Sweeney" /> On 10 February 2010, 172 Mini-500s remained on the [[Federal Aviation Administration]] registry, with an additional 81 registrations cancelled (although registered, this does not necessarily indicate these aircraft have flown).<ref name="FAAReg">{{cite web|url = http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=&Modeltxt=MINI-500&PageNo=1|title = FAA Registry - Make / Model Inquiry Results|accessdate = 2010-02-10|last = [[Federal Aviation Administration]]|date = February 2010|archive-date = February 29, 2012|archive-url = https://web.archive.org/web/20120229093022/http://registry.faa.gov/aircraftinquiry/AcftRef_Results.aspx?Mfrtxt=&Modeltxt=MINI-500&PageNo=1|url-status = dead}}</ref>

Of those that did fly there were many component failures, dozens of accidents and incidents and nine fatalities. The aircraft quickly developed a poor safety reputation and this curtailed kit sales.<ref name="Sweeney" />

The [[Rotax 582]] two stroke engine proved to be underpowered in this application and many failed in flight. The engine's vibration levels also proved to be a problem as they, combined with excessive rotor vibrations, led to cracked frames and other component failures.<ref name="Sweeney" />

Owners complained that the aircraft was not well designed. The president of the International Experimental Helicopter Association, the Mini-500 [[aircraft type club]], Bill Phillips, who completed a kit, but did not fly it stated: "You can tell it is junk just by looking at it" and described Revolution Helicopter Corporation president Dennis Fetters as "one of the biggest cons that’s ever hit the kit industry".<ref name="Sweeney" />

Fetters strongly denied that the design had safety issues and issued statements indicating that all accidents were due to improper maintenance, failure of builders to carry out rotor tracking and balancing or lack of piloting skills. In response to customer complaints in 1998 Fetters did add a tuned exhaust system to increase engine output, stronger transmission gears and a mast support kit to reduce vibrations.<ref name="Sweeney" />

===Rotax 582=== Engine manufacturer [[Rotax]] warns owners of the 582 engine in the Owners Manual about its limitations:<ref name="RotaxOwnersMan">{{cite web|url = http://www.rotax-aircraft-engines.com/portaldata/5/dokus/d04495.pdf|title = OPERATORS MANUAL FOR ENGINE TYPES 447, 503 & 582|accessdate = 2009-03-09|last = [[Rotax|BRP-Rotax GmbH & Co. KG]]|year = 2006}}</ref>

{{quotation|"This engine, by its design, is subject to sudden stoppage. Engine stoppage can result in crash landings, forced landings or no power landings. Such crash landings can lead to serious bodily injury or death ... This is not a certificated aircraft engine. It has not received any safety or durability testing, and conforms to no aircraft standards. It is for use in experimental, uncertificated aircraft and vehicles only in which an engine failure will not compromise safety. User assumes all risk of use, and acknowledges by his use that he knows this engine is subject to sudden stoppage ... Never fly the aircraft equipped with this engine at locations, airspeeds, altitudes, or other circumstances from which a successful no-power landing cannot be made, after sudden engine stoppage. Aircraft equipped with this engine must only fly in DAYLIGHT VFR conditions."<ref name="RotaxOwnersMan" />}} This statement is supported by the 16 fatalities when operating the Mini 500.

==Variants== ;Mini-500 :Original version, empty weight {{convert|330|lb|kg|0|abbr=on}}<ref name="Aerocrafter">Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook, Fifth Edition'', page 328. BAI Communications, 15 July 1998. {{ISBN|0-9636409-4-1}}</ref> ;Mini-500B :Improved model with upgraded tail rotor tips, main transmission, rotorhead and [[airframe]]. Empty weight {{convert|485|lb|kg|0|abbr=on}}<ref name="Aerocrafter"/>

==Specifications== [[File:VH-BJC Revolution Mini-500 (8543314751).jpg|right|thumb|Revolution Mini-500 instrument panel]] {{Aircraft specs |ref=Taylor<ref name="Brassey">Taylor 1996, p. 356</ref> and Southeast Recreational Helicopters<ref name="Max">{{cite web|url = http://www.max-designs.com/helo/info.htm#specs|title = Performance Specifications|accessdate = 2009-07-11|last = Southeast Recreational Helicopters|date = January 2006|archive-date = 2016-03-03|archive-url = https://web.archive.org/web/20160303210751/http://www.max-designs.com/helo/info.htm#specs|url-status = dead}}</ref> |prime units? = imp |crew=1 |length m=6.9 |length ft=22 |length in=6 |rot number=1 |rot dia m=5.79 |rot dia ft=19 |rot dia in=0 |width m=1.6 |width ft=5 |width in=3 |height m=2.5 |height ft=8 |height in=1 |empty weight kg=150 |empty weight lb=330 |gross weight kg=372 |gross weight lb=820 |eng1 number=1 |eng1 name=[[Rotax 582]] piston engine |eng1 kw=48 |eng1 hp=64 |max speed kmh=186 |max speed mph=115 |cruise speed kmh=122 |cruise speed mph=75 |range km=361 |range miles=225 |endurance=3 hours 0 minutes |ceiling m=3,050 |ceiling ft=10,000 |climb rate ms=5.6 |climb rate ftmin=1100 }}

{{aircontent  |see also= |related= |similar aircraft= |sequence= |lists= *[[List of single seat helicopters]] }}

==References==

===Notes=== {{reflist|30em}}

===Bibliography=== {{refbegin}} *{{cite book|last= Taylor|first= Michael J. H.|title= Brassey's World Aircraft & Systems Directory|year= 1996|publisher= Brassey's|location= London, England|isbn= 1-85753-198-1|url-access= registration|url= https://archive.org/details/brasseysworldair0000unse}} {{refend}}

==External links== {{commons category}} *[http://cdn-www.airliners.net/aviation-photos/photos/7/4/1/0584147.jpg Photo of Mini-500 on Airliners.net] *{{YouTube | eu6Ept3htc8 | Demo Video }}

[[Category:1990s United States civil utility aircraft]] [[Category:1990s United States helicopters]] [[Category:Homebuilt aircraft]] [[Category:Aircraft first flown in 1992]] [[Category:Single-engined piston helicopters]]