What's a trike anyhow?

Beginnings

The most popular hang gliders, however, use weight-shift rather than aerodynamic control and have flexible, rather than rigid wings, and have no tails. There are no control surfaces like ailerons or elevators. The pilot controls the aircraft purely by moving his weight below the wing. While this may sound chancey, this kind of aircraft is quite stable and very forgiving. After years of refinement, hang gliders are relatively safe machines.

In most attempts to add power to weight-shift hang gliders through the early from the 1960's to early 1970's, the motor was mounted to the wing itself. Many positions were tried. On top, on the keel at the rear, and even twin engines on booms either side of the pilot. All these were either pitch unstable under power or too dangerous (the rear mounted versions were affectionately known as "toe cutters"). In addition, with the primitive power plants and propeller arrangements of the time, performance was marginal (to say the least!). In addition, weight shift wing technology had yet to undergo the major performance jump of 1980, when Ultralight Products released the revolutionary Comet hang glider. 

So most ultralights from the mid 1970's onward tended to be traditional wing and tail (or canard) designs, with aerodynamic controls.

Enter the "Trike"

All that was necessary was to build a tricycle undercarriage with a pusher prop which was suspended using a pitch and roll joint from the normal pilot suspension point on the hang glider. This put the thrust line in the right position to aid stability, and the rigid structure and rear placement of the propeller protected the pilot. It also made it possible to use a large diameter propeller for additional performance.  This was actually not an original idea. Similar arrangements had been successfully trialed by NASA and others such as Barry Palmer in the early 60's, (shown at right, with permission of Barry Palmer).  

The "trike", as it soon became known, quickly became popular in the UK and France where it had been reborn. It was easy for existing hang gliding manufacturers to diversify and a healthy competition between them soon evolved. It took longer to catch on in Australia, where the small potential market made it hard to justify production, and also the US, where large conventional ultralight industries had already grown up and were heavily entrenched. Even today, trikes are not common in the US. 

Of course, it was only a matter of months before someone decided to put a second seat on one. 

Another factor in the early European popularity was the weather. Frustrated European hang glider pilots flocked to trikes as a way of getting airtime using skills they already possessed, but US and Australian hang glider pilots, enjoying more sun, didn't have the same incentive. 'Petrol heads' have never been a respected group amongst the hang gliding purists in Australia and the US. But as the Australian hang glider pilot population greys, many are trying trikes as a cheap way of getting airtime in between business and family commitments. 

Trikes Today

The performance of modern trikes compares favourably with conventional ultralights. Cruise speeds range from 30 to 70 mph, and trikes have among the most spectacular climb rates of all ultralights.  Comfort has not been neglected, with the addition of partial enclosures (pods) to keep the worst of the wind away. While space-age materials are used in some, most trikes remain based on a pin-jointed aluminium tubing structure, with streamlining as a non-structural add-on. 

The trike remains the most common form of ultralight in Europe, and the more advanced models regularly win or place highly in international ultralight championships. This may not have as much to do with the performance of the trikes themselves as the greater emphasis put on ultralight competitions in Europe and the resulting standard of pilot competition experience. 

So why is it called a Trike, not a Powered Hang Glider

Why Fly A Trike?

Your first flight!

He explains the controls, what there are of them. The control bar or 'A' frame is the primary control for use in the air. With it, you can move the whole trike undercarriage fore and aft and side to side under the wing once airborne. This will control pitch and roll. You have a throttle, but unlike conventional aircraft, it's a foot throttle - just like a car. Both feet are on a steering bar which steers the nosewheel in billycart fashion for taxiing. Your left foot also has a pedal which applies a nose wheel brake. And apart from the ignition switch and the choke, that's all there is! No flaps or mixture control to worry about. 

"Clear Prop!" The instructor reaches up and heaves on the pull-starter (or presses a button if the trike has an electric starter). The engine roars into life, and after a minute or two warming up the engine, the instructor grabs the control bar and straightens the wing. He applies a bit of power, and you begin to taxi to takeoff. 

There's no traffic, the wind is calm and you're all lined up. The instructor eases the control bar out slightly so that the wing is pointing up slightly, centres the nose wheel and eases the throttle to full power. The trike accelerates far more quickly than you expected, and before you know it, the jolting of the wheels stops, the whole undercarriage rotates slightly to point skyward, and you're off! 

As soon as a couple of hundred feet are gained, the instructor eases off the throttle a bit for the engines sake. You are climbing at over 600 feet per minute, and looking over the side, you see the runway dwindle below and behind very quickly. 

At training altitude, the instructor eases off the throttle to cruise power and the aircraft settles into straight and level flight. It's time to learn how to fly. Speeding up and slowing down is easy. Pull the control bar toward you and apply extra throttle to speed up. Ease the control bar away and reduce throttle to slow down. To climb, simply apply throttle and maintain speed (or reduce it slightly to improve the climb rate). To descend, reduce throttle and maintain speed. Turns are more difficult. You try to turn by simply easing the control bar to one side. this starts a turn allright, but rather than a nice flat circle, you find the nose dropping into a slight dive. The instructor explains that just as in a normal plane, a good, co-ordinated flat turn is achieved through pitch as well as roll, plus extra power. He demonstrates, with a little extra speed in the entry of the turn, and when he pushes the control bar to the side, you also notice that he is slowly easing it outward as well. Obviously to do this really well will take some practice. 

Suddenly, you hit some turbulence. You've passed through your own wake! The control bar starts to dance, and it takes some effort to stabilise. There's a bit more physical work in flying a trike in turbulence than a conventional aeroplane! 

Time for a stall now. The instructor reduces power, then asks you to ease the control bar out very slowly. As the airspeed decays, it gets harder and harder to push the control bar forward. The aircraft is resisting the change in speed and attitude. The control bar begins to feel 'loggy'. Then, with very little wind left in your face, the nose falls, the control bar comes 'loose' and the aircraft enters a shallow dive, picking up speed as it does so, then begins to level out. You lost less than 100 feet in the stall. 

After admiring the view and practicing those nice balanced turns, it's time to land. The instructor lines up with the runway and reduces power, and you begin to descend. With the runway only 10 feet below, he begins to ease the control bar out slowly, and you find yourselves flying straight and level only inches above the ground. But without extra power, the aircraft cannot stay there, and gently, it touches down and the instructor applies the brake to bring you to a stop. Time to sign up for lessons!

The Fine Print

All commercially available new trikes are registered as Civil Aviation Order 95.32 category aircraft and are required to have been certified to an acceptable standard. Right now, this includes the Australian and the UK BCAR Section S certifications. All legal 2-seaters belong to this category. Owner-builder category trikes (CAO 95.10) trikes may be re-sold subject to acceptance by the Ultralight or Hang Gliding Federations of a Technical Data Package. 

Trikes can be registered with either the AUF or the Hang Gliding Federation. Both associations may issue Pilot Certificates and endorsements for weight shift ultralights to their members after appropriate training.

Where do you get one?

There is only one commercial certified Trike builder in Australia, AirBorne Windsports, in Newcastle, NSW, who make the Edge 2-seater trike (shown right, click on pic for larger version). Pre-built, certified trikes are also imported from the UK by a number of businesses including many flying schools. These trikes include the two-seat PegasusQuantum (click for pic), Quasar and XL models, and the single-seat Chaser-S, all available through Mark and Jeneane Howard of SkyRiders in Victoria. (Mobile: 018-533731 Fax: 03-97511584 ) 

Prices on new commercial trikes range from $14,000 to $33,000 or so. See the Sourcebook for addresses and phone numbers. 

Second-hand trikes both single and two-seat are available from about $6000 for a serviceable machine, and as always there is the option of building your own from plans or scratch, which will set you back about the same amount. Caveat emptor! You should note that although some second hand machines have 2 seats, many, constructed prior to certification requirements, cannot be legally flown two-up. Check before forking out the readies!

It may be possible to build a 2-seat trike legally. Check out the HuntWing, a 2-seat BCAR-S certified trike that can be built from plans. This is 2-seat legal in the UK, as long as it has been passed by a BMAA inspector. Unfortunately, in Australia, we have no inspector network. Nevertheless, if some enterprising soul would like to build one, there might be a way! 

Instruction

3-axis conversions

Trikes have reverse sense controls compared with 3-axis aircraft.

This means: 

You pull the control bar toward you to speed up, and away from you to slow down.

You move the control bar to the right to turn left and vice versa.

Your nosewheel steering is "billy-cart" style. Push right, go left.

I might add that speaking from personal experience, this also works in reverse. Hang-glider and trike pilots usually find the air work in 3-axis training quite simple, but need to be watched carefully on landing and flare. 

If you become a bi-wingual pilot, to a certain extent, some aspects of your flying will have to cease to be instinctive. When flying a Cessna, I *always* have to consciously remind myself on final what kind of machine I'm flying.

Limitations

Loops are not sanctioned by any manufacturer. A failed loop which results in the trike stalling in an inverted attitude will invariably result in catastrophic structural failure and a very high descent rate.

Trikes have a high power-weight ratio and can acheive very steep climbs. More than one accident has been caused by over-steep climbs terminated by an engine failure, causing a severe stall and tuck/tumble. This is most common where a two-seat trike is being flown one-up. 

Trikes cannot side-slip. In light cross-winds, the approach is to crab up the strip. If you have a machine with a high nosewheel, the mains will touch down first, and the nosewheel will tend to be dragged into line before touchdown along the line of motion. If you have a very flat attitude, the technique is to keep the nosewheel pointed in the direction of motion, and be ready to correct immediately. In stronger winds, find a better strip, or land aslant the runway.