In a world of ultralights populated with powered parachutes, powered paragliders, weight-shift trikes, and all manner of 3-axis ultralights, why not a powered hang glider? Why not return to our roots?
For those too new to the scene to remember, ultralights started out as powered hang gliders. John Moody, the man widely known as the “Father of Ultralights,” first motorized and flew a hang glider called the Icarus II (which evolved into the Easy Riser). Moody’s first ultralight, back in the mid-1970s, had no landing gear and no tail because those appendages weren’t on hang gliders then, or now.
After Moody’s early work – plus that of others in the hang gliding and ultralight community – other pioneers began adding power packages to more conventional hang gliders. The Easy Riser Moody flew had good performance but didn’t break down as efficiently as the fully-foldable “flex wings,” as they are commonly known today. Hang glider pilots overwhelmingly preferred the flexxies and since this created a ready market, some gear heads decided to add power to the hang gliders everyone had rather than the “rigid wings” like Moody had used.
After some early variations the trike was born and today may be the most common type of ultralight/microlight in the world. Indeed, even in the USA after a slow start, trikes appear to be coming on strongly.
Zoom to 21st Century
The quick view of history shows that hang gliders and powered ultralights diverged sharply in the early 1980s with the U.S. Hang Gliding Association electing to discontinue all support for powered aircraft they considered outside their interest or expertise.
For nearly 20 years, the two forms of air sports developed quite independently of one another. Yet in our modern world, no one operates in a vacuum and perhaps it was fate that brought the two back together.
In the early days of hang gliding, the enthusiasts were mostly young, strong-legged fellows. They much preferred to carry their wings by themselves, set them up alone, and launch them from mountains with no assistance. As time passed, these soaring enthusiasts aged and a funny thing happened. Some of them shucked their disdain for power and wheels and begin experimenting again with hang glider wings sporting power packages.
These investigations were distinctly unlike the more utility- or travel-oriented trikes that European trike manufacturers have been selling to America since the late 1980s. No, instead, hang glider soaring enthusiasts wanted the least gear they could carry which would allow them to power-launch.
As the 1990s ended, several superlight trikes had appeared on the U.S. market.
The Cosmos Samba1 is made more like a lightened conventional trike carriage rather than a purpose-designed machine. An Italian company makes a light trike, another featherweight has been reported in Australia, and North Wing offers their new ATF lightweight model.
Despite these other offerings, I doubt any have received more attention to the soaring pilot’s needs than the SkyCycle.
Lookout Mountain Flight Park (let’s shorten that to simply LMFP) may be the most successful hang gliding training organization in the world. This million-dollar-a-year business teaches a large number of students annually.
LMFP also sells more hang gliders than some of the smaller manufacturers produce in a year and also markets other products to hang glider enthusiasts. With a retail shop right alongside their well-known launch site at the top of a long Tennessee/Georgia ridge, they sell it all and lots of it. When something isn’t available on the market or when they think they can improve on an accessory, they make it themselves.
To an organization with the abilities and facilities of LMFP, the trike carriage is merely an accessory. The glider is the aircraft their customers prefer to fly. But flat parts of the country or a desire to power-launch for an after-work flight brings hang glider pilots to the idea of a power pack that can boost them aloft. Add the need for some wheels to ease the jolt to the joints and the lightweight trike chassis can be understood.
Many hang glider pilots see the value of buying just the chassis for a wing already owned. Add this reasonably lightweight rig to your modern state-of-the-art hang glider wing and you’ve got a low-cost motorglider. “Most hang gliders will fit the trike chassis,” assures LMFP boss Matt Taber.
Recently rebadged the SkyCycle from its earlier name, the Freedom Machine, this intriguing ultralight qualifies under FAR Part 103 so easily it’s almost laughable. This means LMFP can fully manufacture and assemble the SkyCycle and sell it to their customers as an ultralight vehicle.
More than 50 owners have already bought into the idea, and the word is still getting out. As I reported in the Cosmos Samba report, these “powered hang gliders” offer another style of flying to 10-15,000 U.S. hang glider pilots (and as many as 60,000 more overseas). If you add those who were intrigued by hang gliding but who never liked the foot-running parts, the market has still-greater potential.
Before fuel or wing are added, the SkyCycle trike chassis weighs only 90-95 pounds, depending on equipment and before a ballistic parachute system is added. To the base chassis add a chute system and fuel in the little 2.5-gallon tank (no more is truly needed), plus the wing and some extra instruments, and you might reach 200 pounds. Since the parachute doesn’t count as part of an ultralight’s empty weight, the SkyCycle is more than 70 pounds under the FAR Part 103 254-pound empty weight limit!
To the hang glider pilot seeking a way up, the general notion is to have the 22-hp Zenoah G25B-1 engine propel you skyward at better than 600 fpm for five or six minutes. At the end of such a short full-power burst, a knowledgeable pilot on a decent day can handily find thermal lift. At such a time, this pilot will kill the engine and concentrate on soaring, maybe for hours, free of charge. That can make the miles per gallon go right off the scale.
Low fuel use and extremely easy starting are characteristics of the Zenoah G25B-1 single-cylinder engine on the SkyCycle. Although LMFP offers a lightweight electric start system now, the engine pulls so easily that the powered starter is a luxury that just adds pounds.
However, even if you don’t care about soaring, the G25B-1 engine has a good reputation for efficiency and power if properly mounted. LMFP put a lot of effort into this task, isolating the vibration-causing single banger engine from the airframe. They also struggled to make the exhaust mount fluid enough that the vibes didn’t cause it to depart the aircraft.
As the principal owner, business manager and main product developer of his ambitious enterprise, Matt Taber brings good experience to the job. A long-time motorcycle and auto enthusiast, Taber has strong mechanical skills. He’s already designed, built, and flown a hang glider tug modeled after the Bailey-Moyes Dragonfly aerotug.
A SkyCycle may be landed off-field by a soaring pilot who lost the lift and then may not have been able to restart. Fortunately for such an aviator, the SkyCycle’s fuel tank is a handy, carryable, easily removed type that reduces spills near the aircraft.
Off-field landings – sometimes called out-landings – are not unusual for soaring pilots. Most are loathe to turn the engine back on because it reveals they lost the lift. Finding and staying in lift is the supreme challenge. After a couple soaring hours, however, the Zenoah may have fully cooled off and resists restarting.
The SkyCycle’s landing gear may look dainty, but it’s proven itself through much test-flying from a grass strip with the usual assortment of bumps and dips. Using only a single steel strut gear leg helps reduce drag and weight and provides adequate strength in most situations.
The SkyCycle also uses a simple form of trailing link nosewheel suspension. Angling the forks aft gives some castoring ability which eases steering duties, especially at faster landing speeds.
Most hang glider enthusiasts would just as soon not deal with the engine at all. Indeed, most will continue to use mountain launches and ultralight tugs to get off the ground. Others find the appeal of one-man operation worth the hassles powerplants can introduce.
The single-banger engine will lift the SkyCycle off terra firma in 75 feet and produces a consistent climb at nearly 600 fpm. Many ultralights with 50 hp can do no better.
Two and a half gallons of fuel ought to last nearly 2 hours of high-power operations and considerably longer if you use the 22 hp to gently boost you along while you search for lift. Carrying more fuel is not necessary for the pilot who finds convective lift.
As Matt Taber and LMFP watched the SkyCycle’s weight carefully, they didn’t leave out features that pilots will appreciate. For example, our test SkyCycle had a 4-point pilot restraint. I was also pleased to find the ballistic parachute system that I prefer when making flight evaluations.
For the hang glider pilot, engine performance measures and powered speed ranges aren’t important. These soaring enthusiasts prefer a low sink rate to let them float upwards in thermal or ridge lift, and a good glide to let them zip to the next thermal with a minimum of altitude loss. The wing LMFP supplies with the bargain-priced SkyCycle – the Wills Wing Falcon 225 – will provide superior sink rate due to its large wing area, but it won’t bring the glide of the topless Wills Wing Fusion glider as shown in the accompanying photographs.
Like all matters of aviation, here is another tradeoff. To get the sink rate needed to perform optimally with the added weight of the trike carriage, more wing area is useful. However, a big wing with a thick airfoil won’t zoom between thermals due to its narrower speed range. Conversely, the topless hang glider wing can accelerate smartly, but doesn’t have the area to provide the lowest sink rate. In the future, new rigid wings may change this dilemma.
Presently if you’re a hardcore soaring pilot (meaning you are interested in power-off distance cross-country flying), or if you are a power-only ultralight pilot, the better choice would be the topless wing. It can cruise faster, is more modern, and can penetrate headwinds better.
However, if you are a recreational hang glider pilot just looking to catch a few fun thermals on weekends or after work, the larger (lower gliding) wing is probably the better choice.
Intriguingly, the two will probably handle similarly due to the differences in how the wings are optimized.
The larger, “looser” wing is more roll responsive and the smaller, tighter wing is more highly loaded, giving it a snappier roll. In both cases, pitch forces will be light until you reach a design speed where pitch becomes highly stable. More than 30 years of vigorous hang glider design, the state of the art has advanced impressively, making the wings these pilots fly quite sophisticated and very predictable.
One feature on the topless wing is different than any other aircraft. Called a “VG” for Variable Geometry, a line runs inside one control bar downtube up to a pulley system that draws the crossbar back tighter. This forces the leading edges out, creating higher spanwise tension across the wing. The delta wing shape rewards such tension with greater speed, a tauter wing less likely to distort at speed, and a leaner airfoil section able to better penetrate headwinds. At will, the pilot can add or decrease tension. More slack means better handling at low thermal flying speeds. Greater tension means stiffer handling but higher speeds with less performance loss.
Manufactured by Wills Wing, the Falcon 225 the SkyCycle comes with, or the optional 150 Fusion topless model, are certified under several international standards and have proven themselves to be airworthy wings. Wills Wing hang glider wings are highly regarded throughout the world.
Hang gliders are torture-tested in ways not possible for most other aircraft. Using high-powered trucks, hang glider designers mount their gliders in free air well above the truck using a large tubular structure firmly mounted to the truck. They subject the gliders to real-time forces by driving the trucks 80 mph while holding the glider fixed at punishing angles. Engineers can also extensively measure pitch responses in a highly-evolved certification system.
The Fusion glider wing in these photos held a load of 2,000 pounds without permanent deformation, giving it nearly a 6-G positive rating for ultimate load.
Fun, Small, and Well-Priced
Your garage could hold a half dozen SkyCycles folded for travel. They simply don’t take up much space, folding to a compact form. Two SkyCycles could fit in a standard-sized pickup truck with a little creative planning.
Lifting it by yourself is even reasonable if you employ some leverage given an empty rig as light as 90 pounds. The wing is separate and weighs about 65-85 pounds, depending on the type. Although the packed wing is 20 feet long, it hefts onto your shoulder with a little knack and can be carried or placed on a car top by one person.
Lightweight and small engines help LMFP price the SkyCycle chassis for $5,500, ready to fly. That doesn’t include a wing but new choices are available from $3,500-6,000. Good used glider wings may be half those amounts. For a limited time LMFP is offering the SkyCycle with Falcon wing for $6,995, an excellent bargain.
Select a top-end hang glider like the Fusion and the SkyCycle could hit $12,000 ($5,500 for chassis and $6,000 for wing plus some shipping). However, you can get 12:1 glide performance and sink rates around 250 fpm. Given a used wing, you could get airborne for around $8,500 and have a pretty capable aircraft that can easily qualify under Part 103.
Many Ultralight Flying! readers may not care to try foot-launched hang gliding, but with a trike chassis, sampling this unique form of flight will be more comfortable to pilots accustomed to powered ultralights.
The idea of a low-cost, fun-to-fly ultralight that’s fully built, easy to fold, carry, and store is always worth consideration.
1 See “UF! Pilot’s Report: Doin’ the Samba,” April ’98 Ultralight Flying! magazine.
|Empty weight||(chassis only) 90-115 pounds1, (wing and chassis) 155-175 pounds2|
|Gross weight||450 pounds2|
|Wing area||156 square feet|
|Wing loading||2-3.5 pounds per square foot 2|
|Kit type||Fully assembled|
|Notes:||1can vary depending on optional equipment.
2depends on wing used.
|Standard engine||Zenoah G25B-1 single cylinder|
|Power||22 hp at 6600 rpm|
|Power loading||20.5 pounds per horsepower|
|Cruise speed||35 mph|
|Never exceed speed||54 mph1|
|Rate of climb at gross||500-600 fpm|
|Takeoff distance at gross||75 feet|
|Landing distance at gross||100 feet|
|Notes:||1depends on wing used.|
|Standard Features||Wills Wing Falcon 225 wing (many other choices work with this 95-pound trike), in-flight recoil starting, 2.5:1 belt reduction with 52-inch prop, light weight-shift control, steerable nosewheel with trailing link design, 4130 steel main gear, 2.5-gallon fuel tank.|
|Options||Many other wing choices, electric starting, 3-blade composite prop, fairing and wheel pants are in development (available March 2000, says manufacturer), engine and flight instruments, ballistic- or hand-deployed parachute.|
|Construction||6061-T6 aluminum tubing chassis, 4130 chromoly welded steel, AN hardware, Dacron® sailcloth.|
Cosmetic appearance, structural integrity, achievement of design goals, effectiveness of aerodynamics, ergonomics.
Pros – All-new, all-American trike chassis design intended to be connected to any number of modern hang glider wings. Built ready-to-fly. Uncomplicated construction saves weight and reduces drag significantly (compared to conventional trikes). Though simple, the SkyCycle’s design is well-conceived and has what it needs to get the job done. Now powder coated and with a strengthened front fork. Manufacturer is a long established, secure and successful enterprise.
Cons – No matter that it reaches its goals, the SkyCycle isn’t for most ultralight pilots; neither will purist hang glider pilots embrace the SkyCycle. Overall finish is not as slick and professional as heavier European trikes (new powder coating improves the finish). No 2-place SkyCycle is available for instruction. Sink rate and glide suffer from chassis drag (versus hang glider only). Manufacturer is primarily a hang glider enterprise not focused on powered ultralights.
Subsystems available to pilot such as: Flaps; Fuel sources; Electric start; In-air restart; Brakes; Engine controls; Navigations; Radio; (items covered may be optional).
Pros – Despite its simplicity, the SkyCycle has a kind of in-flight trim (part of the hang glider wing; called variable geometry) which can noticeably shift your speed range. Overhead pull starting works quite effectively and can be used while seated (e.g., after a day’s soaring with the engine off). Optional electric start system available. Easy access to all components.
Cons – Design is so simple and compact that adding features will be challenging; such additions can also detract incrementally from the design’s goals as a soaring machine. No hand throttle to complement foot throttle (as most heavier trikes have). No flaps or other landing aid devices currently available.
Instrumentation; Ergonomics of controls; Creature comforts; (items covered may be optional).
Pros – Thanks to its hang glider heritage, the SkyCycle has plenty of instruments in the lightest, smallest package ultralight pilots have seen. Four-point seat belts on test ultralight; 3-point now listed as standard. Entry and exit can hardly get easier. Seat is adequately padded.
Cons – What “cockpit?” Deliberately-minimalist design (to optimize engine-off soaring performance) offers little in amenities like pockets or instrument/radio panels. No pilot protection for cold climate operations; bundle up. Not designed to take stuff with you.
Taxi visibility; Steering; Turn radius; Shock absorption; Stance/Stability; Braking.
Pros – Very responsive in taxi mode. Tight turn radius is possible. Nosewheel steering benefits from trailing-link design and a new, stronger aluminum construction on models after our flight-test trike. Visibility is excellent thanks partly to a wing that can be pivoted out of the way if needed. Gear is much tougher than it looks; able to cope well with off-field landings. Plenty of prop clearance also helps in rougher fields.
Cons – No brakes offered, though arguably they aren’t needed in this type of ultralight (a soaring pilot’s “launch system”). As with all trikes, gusty winds require much more muscle to hold craft stable while taxiing.
Qualities; Efficiency; Ease; Comparative values.
Pros – Simple straightforward takeoff and landing characteristics – if you know your wing; high-performance models may be more challenging. Simple gear construction seems to do well on bumpy surfaces. Massive visibility on landings. Good climbout power (600 fpm initially) is adequate at most air parks. Good clearance – chassis and prop – allow rougher-field landings. High- performance hang glider wings offer excellent energy retention.
Cons – No trike is good at crosswind landings. No flaps or other landing aid and no true slip potential force you to plan your landings better and learn new approach techniques (like S-turning). Lack of brakes may limit use on some surfaces. Takeoff traffic visibility is somewhat limited by large, close overhead wing.
Quality and quantity for: Coordination; Authority; Pressures; Response; and Coupling.
Pros – Modern hang glider wings optimize weight-shift control to its fullest potential. Also benefiting from greater wing loading, overall control is light and highly responsive. Surprisingly quick roll rate without high muscular effort. Very light pitch that is at the same time very stable. Variable geometry changes speed range and control forces noticeably.
Cons – Many references to 3-axis control (like dutch roll exercises and adverse yaw) don’t directly apply to weight-shift. Three-axis pilots definitely will have to concentrate at first (though it is actually much simpler than 3-axis). Even among trike pilots, these powered hang glider trikes may seem unusually responsive.
Climb; Glide; Sink; Cruise/stall/max speeds; Endurance; Range; Maneuverability.
Pros – Climb with the little 22-hp Zenoah engine is sprightly, at 500-600 fpm “even with heavier pilots,” says LMFP. Lean, simple construction aids soaring goals by reducing frontal area and drag; very light chassis weight also helps. Wheel pants are planned as is a nose fairing. Sink rate and glide performance are very good, even with the added drag of the trike chassis (compared to a hang glider).
Cons – Sink rate and glide angle of the supporting wing are compromised by the drag of the chassis. Design begs to have lightweight fairings over the square mast, front support tube, and gear parts (see above note about added drag). Wing is loaded higher than optimal for original design, as though flown by a heavy pilot at the top of the recommended weight range.
Stall recovery and characteristics; Dampening; Spiral stability; Adverse yaw qualities.
Pros – Hang glider wings are extensively tested and industry certified in a tough program. Very positive in all normal flight regimes. Stall characteristics are positive, though the nose can break somewhat sharply. Powered characteristics are positive even during power changes. Good seat restraint and ballistic parachute were appreciated.
Cons – Hang glider wings are built with anhedral, deliberately lessening roll stability; aids overall handling but can result in tightening spirals if uncontrolled. Tailless aircraft can experience tumbles in strong soaring conditions (though trike chassis actually lessens this possibility and, for the record, this can also happen to tailed aircraft).
Addresses the questions: “Will a buyer get what he/she expects to buy, and did the designer/builder achieve the chosen goal?”
Pros – Bargain deal at $6,995 currently available (time limited). Normally sold as chassis and you add the hang glider you may already own. The SkyCycle is a very attractive choice for aging hang glider pilots wanting to do some soaring without the foot-landing effort. Allows complete power-launch and lift to the thermals; climbs vigorously at 500-600 fpm even with heavier pilots. Excellent flight characteristics which vary with the wing you select. No building hassles. Easy, compact storage. Qualifies under FAR Part 103 with room to spare.
Cons – Trike chassis is sold as adaptable to many wings (that you may already own), but unless you buy the wing ready-to-fly from the manufacturer, you have a duty to determine if the wing is appropriate and to assure the correct attach point. Limited market (single-seater aimed at soaring flight) may lower eventual resale, at least in a fast sale. Simply put, this ultralight won’t appeal to many ultralight enthusiasts.