Eagle Helicycle

infobox Aircraft
name = Helicycle
type = Homebuilt helicopter
manufacturer = Eagle R&D



caption = Helicycle N727X at Homer Bell's 22nd Annual Helicopter Fly-in, July 14, 2006
designer = B.J. Schramm
first flight = September, 1997
introduced =
retired =
status =
primary user =
more users =
produced =
number built = 33+
unit cost = US$38,000
developed from =
variants with their own articles =

The Helicycle is a single-seat, single, semi-rigid main rotor helicopter powered by a turboshaft engine. Manufactured by Eagle R&D in Nampa, Idaho as a kit, the aircraft is intended to be assembled by the owner and is considered a homebuilt aircraft. The Helicycle was conceived and designed by B.J. Schramm, the founder of Rotorway International.

Development

Schramm's concept for the Helicycle was to provide a kit for building a reliable, high-performance, real helicopter for a reasonable cost to individuals (on the order of a mid-priced SUV). Fabrication and assembly skills only require being able to accurately drill holes, bend sheet metal and tubing, install fasteners, run wiring, etc. (e.g., no welding or highly-specialized aviation-specific tools are required). Kits are delivered in six increments, including the frame and skids, engine, transmission, main rotor subassembly, tail rotor subassembly, controls and linkages, cockpit exterior/interior, and fuel and electrical subsystems. Assembly instructions are provided in the form of video clips on video CDs (Video CDs) or DVDs, blueprints, and checklists.

Operational history

As of March 2008, five runs of about 30 kits each have been delivered to builders, for a total of about 160 kits, of which 33 have been completed and are flying, with another kit being completed every other month, on average (delivery of a sixth run is scheduled to start in 2008, and orders for a seventh run may be taken, starting in the Summer of 2008, with deliveries to start in 2009). A unique feature of the kits is that a factory checkout must be completed by a factory-designated airframe and power plant technician and test pilot before the builder is allowed to fly the aircraft. The factory withholds a few critical components needed for flight, which the factory representative brings to the checkout.Fact|date=April 2008 In order to ensure that prospective pilots have the necessary flight skills, builders must have at least a solo endorsement from a certified flight instructor (CFI) for flying a Robinson R22 commercially-built helicopter.Fact|date=April 2008

The total number of hours accumulated on all Helicycles flying is estimated to be well in excess of 1,000 flight hours, with one fatal accident, attributed to altitude estimation error by the pilot while flying over water into a low sun angle.Fact|date=April 2008 There have been several accidents and incidents where Helicycles have lost power in/near hover, resulting in minor damage to the skids and some airframes, but no serious injuries. Most of these were attributed to a radio-frequency interference (RFI) problem with the electronic governor. The issue was reportedly solved with better shielding in 2005.Fact|date=April 2008 At least one accident may have been caused by a crack in a fuel line due to lack of mechanical support between a manifold and a fuel injection port.Fact|date=April 2008 Another accident involved flight into high-voltage power distribution wires, but the aircraft was able to fly again, following repairs, and the pilot was not seriously injured.Fact|date=April 2008

Design

Specific design features include a fully-harmonized rotor, modulated collective pitch system, very low twice-per-revolution vibration level due to elastomeric thrust bearings, sufficient flapping angle for low-"G" maneuvers and slope landings, control friction devices, and electronic throttle control (governor).

The feel of the controls in the Helicycle is modeled after that of the Robinson R22, such that quick stops and autorotations are performed similarly in both aircraft, reportedly allowing new pilots to transition to flying their kits with minimal adjustments.

Maintenance

Maintenance primarily consists of visual inspection of all structural components, wiring, and moving parts outside the power plant, and lubrication of bearings every 100 hours of operation.Fact|date=April 2008 The time between overhaul (TBO) of the aircraft is estimated to be 1,500-2,000 hours.Fact|date=April 2008 The track record of the Solar T-62 gas turbine power plant in military applications (CH-46 Sea Knight and CH-47 Chinook auxiliary power units) is reported to be excellent. So much so, that the maintenance schedule essentially consists of inspection of the power plant interior at 1,000 hours and overhaul of the power plant when wear is measured beyond established tolerances.Fact|date=April 2008

pecifications (Helicycle)

aircraft specifications
plane or copter?=copter
jet or prop?=prop
ref={Eagle R&D} [cite web|url=http://www.helicycle.com/Specs/Helicycle%20Turbine%20Specs.htm|title=Helicycle Specs|last=|first=|date=|accessdate=2008-04-13|work=|publisher=]

crew= 1
length main= 20 ft 10 in
length alt= 6.35 m
span main= 19 ft 10 in
span alt= 6.05 m
height main= 7 ft 4 in
height alt= 2.23 m
area main= 308 ft²
area alt= 28.6 m²
empty weight main= 500 lb
empty weight alt= 227 kg
useful load main= 220 lb
useful load alt= 100 kg
max takeoff weight main= 850 lb
max takeoff weight alt= 386 kg
more general=
engine (prop)= Solar T62-T32
type of prop= turboshaft
number of props= 1
power main= 160 shp
power alt= 119 kW
max speed main= 96 knots
max speed alt= 110 mph, km/h
cruise speed main= 83 knots
cruise speed alt= 95 mph, 153 km/h
range main= 140 nm
range alt= 160 mi, 257 km
ceiling main= 11,000 ft
ceiling alt= 3353 m
climb rate main= 900 ft/min
climb rate alt= 4.6 m/s
more performance=

ee also

*Homebuilt aircraft

aircontent
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References

* [http://www.eaa25.org/onfinal/eaa252004-07.pdf EAA Chapter 25 July 2004 newsletter article describing Ami Sela's Helicycle construction project]
* [http://ntsb.gov/ntsb/brief.asp?ev_id=20040505X00557&key=1 Helicycle N3275Q NTSB accident investigation probable cause finding]
* [http://ntsb.gov/ntsb/GenPDF.asp?id=SEA04LA074&rpt=fa Helicycle N3275Q NTSB accident investigation factual report]
* [http://www.swaviator.com/html/issueJF03/Helicycle1203.html SW Aviator Magazine article on the Helicycle]
* [http://www.experimentalhelo.com/eh_whoBuildsHelicopters.htm February 2007 "Experimental Helo" magazine on-line article "What Kind of Person Builds a Helicopter?"]
* [http://www.kitplanes.com/issues/21_9/exploring/28-1.phtml September 2004 "Kitplanes" magazine article "B.J. Schramm - A Homebuilding Legend"]
* [http://www.kitplanes.com/issues/20_12/back_issues/6934-1.phtml December 2003 "Kitplanes" magazine article (p. 7) "First Solar T-62 Turbines Available for Helicycle"]
* [http://www.pra73.net/NewslettersPDF/OnlineSep2003_NL.pdf September 2003 "The Great Northwest Sport Rotorcraft Association" newsletter observations of the turbine-powered Helicycle, and discussions with factory-designated checkout technician and test pilot Doug Schwochert]
* [http://www.kitplanes.com/issues/20_2/back_issues/7014-1.phtml February 2003 "Kitplanes" magazine article (p. 15) "It's Turbine Time for the Helicycle"]
* [http://www.kitplanes.com/issues/19_1/back_issues/6703-1.phtml January 2002 "Kitplanes" magazine article (p. 81) "Miracle Machine? B.J. Schramm's Helicycle may rewrite the standards on homebuilt helis"]
* [http://www.nweaa.org/judging/Judging2001.cfm 2001 EAA Arlington Fly-In Judging Results - Helicycle N3275Q voted Grand Champion Rotorcraft]
* [http://www.kitplanes.com/issues/17_2/back_issues/6284-1.phtml February 2000 "Kitplanes" magazine news item (p. 4) "Around the Patch: What's up with the Helicycle?"]
* [http://www.eaa.org/benefits/sportaviation/index.html October 1997 "Experimental Aircraft Association Sport Aviation" magazine (p. 46) B.J. Schramm's Helicycle Motorcycle of the Air]
* [http://www.kitplanes.com/issues/14_10/back_issues/5486-1.phtml October 1997 "Kitplanes" magazine news item (p. 88) "The Business Side: A new compound helicopter flies in Idaho (Helicycle)"]
* [http://www.kitplanes.com/issues/12_10/back_issues/4845-1.phtml October 1995 "Kitplanes" magazine news item (p. 4) "Around the Patch: Helicycle, new kit from B. J. Schramm"]
* [http://www.kitplanes.com/issues/24_2/builder_spotlight/7788-1.phtml "Kitplanes" magazine 2007 Aircraft Directory]
* [http://www.kitplanes.com/issues/23_2/annual_directory3/7431-1.phtml "Kitplanes" magazine 2006 Light-Sport Aircraft and Rotorcraft Directory ]
* [http://www.kitplanes.com/issues/22_2/homebuilt/1070-1.phtml "Kitplanes" magazine 2005 Trikes, 'Chutes and Rotorcraft Directory]

External links

* [http://www.helicycle.com Eagle R&D factory website]
* [http://www.eaa.org/homebuilders/list/Helicycle_Sled.asp Experimental Aircraft Association WWW page about Tom Sled's Helicycle N3722T] completed during the centennial year of the celebration of the Wright brothers' first flight - Tom's first Helicycle flight occurred within five minutes of the 100th anniversary of the Wright's first flight on 17 December 1903