User:Snaildrake
Hi-
A bit about me: I have degrees in German and English literature and linguistics, and my lifelong interest is writing. I'm an ex- marketing director who burned out on the insane pace of the software industry and became self-employed. So now I write Web and marketing material for the software industry as well as consult on marketing communication.
My entry point to writing for Wikipedia is aviation, specifically homebuilt experimental planes. There is a lot of room to improve and expand the information on homebuilt aircraft to serve the needs of those researching the range of options available to them - industry information tends to be spotty and outdated at best.
As of November 2010 I'm working on an article on the Spacewalker II homebuilt aircraft. Here is the draft:
Spacewalker II[edit]
The Spacewalker II is a 2-seat open-cockpit low-wing monoplane for homebuilding. The Spacewalker II was designed by the United States engineer Jesse Anglin to provide the experience of flying popular 1930s "sportsman" craft like the Ryan ST, with a design that is simple and inexpensive to build and maintain. Its advantages include good speed and economy per horsepower as well as docile handling in flight.
The Spacewalker II has a chromoly steel tube and fabric fuselage and tail, with a wooden cantilever wing and a conventional or taildragger landing gear. The tandem design can be flown with one or two occupants, as the front passenger seat is placed on the fore-and-aft center of gravity so that it can be flown empty without affecting the aircraft's balance. Kits and plans have been available from several successive companies since 1990. As is common in the kitbuilding industry. Over 100 examples have been built and flown.
Development[edit]
The prototype single-place Spacewalker flew in 1986 with a 65HP Continental engine and featured the tube and fabric fuselage, cantilever wing and taildragger landing gear which are common to all succeeding versions. The Spacewalker's early promoters were Maxey Hester and Hazel Sig, owners of the model airplane maker Sig Manufacturing Co, who flew their personal aircraft at many fly-ins around the US.[1]
The two-place Spacewalker II was developed by 1990, with Hester and Sig building the first two prototypes, which were exhibited and flown at the 1990 EAA Oshkosh fly-in. Anglin Engineering supplied kits with the fuselage, empennage and landing gear prewelded, which the homebuilder completed by constructing the wing, assembling and covering the aircraft, and installing the instruments, engine, and other systems. Plans were also available to allow the Spacewalker II to be "scratch-built".[1]
In 1993 Spacewalker builder Rick Warner founded Warner Aircraft to take over production and sales of Spacewalker plans and kits. Warner's derivation was named the Revolution II.[2] Warner Aircraft was sold to Dana Axelrod, who as of 2010 continues to operate the company under the same name. Under Axelrod, Warner brought out a substantial redesign, the Sportster, with a larger fuselage and cockpit, an elliptical wing shape, and an enclosed canopy option.
Serenity Aviation acquired the U.S. rights to the Revolution designs from Warner Aircraft in 2006, and the Australian rights in 2007. Serenity sells plans and kits from its base in Australia (formerly Southeast Asia), once again using the Skywalker name. In 2009 Builder Martin Hone developed a higher performance Spacewalker II-RR with a 150 HP Rotec radial engine. The SWII-RR has a 132 mph top speed (212 kph), 115 mph cruise at 65% power (185 kph), and a climb rate of 1500 feet per minute (7.62 m/sec). SWII-RR conversion plans are available direct from Hone, through Serenity, or the Yahoo Spacewalker group.
Design[edit]
The low-wing Spacewalker II provides an open-cockpit alternative to parasol wing craft and biplanes, its distinguishing feature being an aerodynamically efficient cantilever wing, in contrast to the high-drag strut- and wire-braced wings of other homebuilt aircraft such as the Pietenpol Air Camper, the Bakeng Deuce, and the Bowers Fly Baby. The Spacewalker II features a welded 4130 chromoly steel fuselage and empennage with fabric covering, a cantilever wing with wooden spars, differential Friese alierons, sprung conventional or taildragger landing gear, and Continental or Lycoming engines from 85 to 115 horsepower.[1]
Warner Aircraft brought in aeronautical engineer Ernie Brokaw to perform a design analysis on the Spacewalker designs. As a result the thickness of the steel strap connecting the wings to the wing root in the Warner Revolution II was increased from 0.080" (2mm) to 0.100" (2.5mm). Other minor modifications were made to simplify or improve construction.[2]
Warner later developed the design into the kit-built Sportster, which enlarged the cockpit by 3 inches and lengthened the fuselage by 7 inches for increased comfort and baggage space, altered the wing to a more classic elliptical shape and offered two enclosed canopy options for extended season flying.[3]
Serenity Aviation Spacewalker II kits are available with a completed fuselage, landing gear, engine mounts, and other welded components. To enable construction without exceptionally long aircraft spruce spars, the standard Spacewalker II wing is of three-piece construction, with a combination I-beam and box main spar of plywood and spruce caps, with plywood ribs and a plywood leading edge. Wing flight loads are carried by 4130 steel truss attachments between the front and rear spars. Aileron controls are push-tube with a 40% differential to reduce adverse yaw, while the rudder and elevator are cable-controlled.[4] Flaps are not used.
The aircraft was designed to be powered by an 85 to 100 horsepower Continental or 115 horsepower Lycoming O-235 piston engine. Engines of up to 150 horsepower have been fitted, including the 125HP Lycoming O-290, 150HP Rotec R-3600 and converted Chevrolet Corvair engines rated at 100HP for aircraft use. One or two builders have used inline engines like the Walter/LOM M332 with a fully enclosed cowling to emulate the streamlined appearance of the Ryan ST.
Regulations[edit]
In the United States of America the Spacewalker II was registered before 2005 as an Experimental Amateur-Built (EA-B) aircraft, which may be flown by those with a Private Pilot or Recreational Pilot license. Since the advent of the Light Sport Aircraft classification in 2005, another option for new Spacewalkers is registration as a Light Sport Aircraft (LSA). LSA may be flown in the US by pilots holding a Sport Pilot certificate. A Spacewalker II registered under LSA would have a maximum gross weight limit of 1320 pounds compared to the 1400 pound gross used under EA-B registration.
Specifications (Spacewalker II)[edit]
Data from Serenity Aviation web site[4]
General characteristics[edit]
- Crew: one pilot, one passenger
- Length: 19 ft 9 in (6 m)
- Wingspan: 28 ft (8.54 m)
- Height: 65 in (1.65 m)
- Wing area: 126 ft² (11.7 m²)
- Empty weight: 800 lb (363 k
- Max takeoff weight: 1400 lb (635 kg)
- Powerplant: 1× Lycoming O-290 flat-four engine, 125 hp (93 kW)
Performance[edit]
- VNE: 140 mph (241 km/h)
- Maximum speed: 120 mph (193 km/h)
- Cruise speed: 110 mph (177 km/h)
- Stall_speed: 42 mph (68 km/h)
- Range:
- Rate_of_climb: 1200 ft/min (6.1 m/s)
- Wing_loading: 10.5 lb/ft² (51.3 kg/m²)
- Power/mass:
References[edit]
- ^ a b c Sport Aviation, July 1990, "Spacewalker II", Jack Cox
- ^ a b Sport Aviation, December 1995, "Revolution II: Scarf in the Wind Aviating", Bud Davisson Cite error: The named reference "SportAvRevII" was defined multiple times with different content (see the help page).
- ^ Sport Aviation, May 2000, "It Flies Like Fun", Ed Kolano
- ^ a b Serenity Aviation web site, retrieved 11/10/2010