Thursday, September 16, 2010

Flying the Belite Ultalight Aircraft - Part 2

Editor's note - this is Part 2 of our series on how to fly a Belite Ultralight Aircraft.  


With the horizontal stabilizer trim set properly, the Belite will have a fairly neutral stick feel during climb.  (If it doesn't, continue to fly the airplane, and trim the airplane after landing (or during cruise, if equipped with electric trim).  As previously mentioned, a climb speed of 45 to 50 mph works well.   Your rate of climb is dependent on many factors:  weight, temperature, engine power, propeller pitch, etc., but will vary between 100 to 1000 fpm.  In a brisk wind, the climb angle can seem quite dramatic.   In fact, with a little headwind, an absolute altitude gain of 800 feet over a ground distance of 1/2 mile is achievable!

You will notice that the ailerons are light and responsive and the rudder coordination will be needed to offset P factor and adverse yaw.  While the yaw effect caused by ailerons is not pronounced, application of the rudder in the same direction of the flaperons will result in nicely coordinated turns.  (This becomes automatic after some flight time is accumulated.)

Belite's slip-skid indicator can help with rudder coordination, but I've learned to fly the aircraft with absolutely no instruments installed -- you can too, if you want. 

The Belite ultralight aircraft is highly sensitive to angle of climb -- the plane will quickly slow down (and stall) if pulled up; conversely, a nose down attitude will result in a rapid airspeed increase and stall recovery.  As you gain experience, you will wish to experiment with pitch control to get a better idea as to how the Belite relates to pitch versus airspeed changes. 

By the time you are one hundred feet off the ground, you may notice that your aircraft has no doors.  Even so, there is very little airflow in the cabin area and there is no sense of buffeting by air moving past the 'no doors'.  Do not let the 'no door syndrome' distract you from flying your new ultralight airplane.

On your first flight, climb to a safe altitude and stay in the pattern.  You may wish to circle the pattern several times before landing the Belite.

But before landing let's consider some flying basics.

Level Flight and Flight Maneuvers

Level flight can be determined by checking your altimeter and VSI, like any conventional aircraft, and adjusting stick and power to neutralize climb.  Your indicated airspeed will settle in at 55mph (with a 28HP engine) to 62mph (with a 38HP engine) to 70+mph (with a 50HP engine, in experimental configuration).   With the horizontal stabilizer properly trimmed, the control stick should have a neutral feel.  Small pitch and power changes can be made to maintain level flight.  A low horsepower engine will lose RPM and power quickly when the nose is raised.  Conversely, it will gain RPM when the nose is lowered.  Don't chase level flight -- trim your aircraft properly (either on the ground, with a fixed elevator tab, or in the air, with electric trim).  Then set the power and let the airplane settle down, like any other airplane.

Turns in the Belite ultralight aircraft are made in the same manner as previously described in the 'climb' section.  Remember to practice great rudder / aileron coordination.  The rudder needs to be moved only when moving the ailerons.  Once a turn is started, the airplane will continue to turn even if the controls are neutralized.  Consequently, turns are stopped by applying a small amount of force in the opposite direction.  Practice safety when turning:  the excellent visibility of the Belite allows the pilot to look right, left, and backwards before a turn is started.  You should even look overhead, which is easily done through the clear top windshield.  This also allows you to see into a turn, as it is begun.

Always observe safe airspeeds:  maintain Vx or higher (45 mph) in climb or slow flight, unless practicing stalls.  The airplane will stall at approximately 28mph indicated airspeed, at sea level, when loaded with a 170 pound pilot, with full flaps, under standard atmospheric conditions.   The airplane will stall at 34mph indicated airspeed, at sea level, when no flaps are selected.

Do not exceed 65mph, except in smooth air.  Never exceed 80mph under any circumstances, it is the red line (Vne) of the airplane. 

Once you are comfortable in level flight and turns, begin to practice flying at speeds that are less than normal cruise.  Reduce power slightly and slow the plane to 45mph; this is a good to practice slow flight at.  You will be able to maintain level flight at this power settings, although it may require some work. 

If you add one notch of flaps, you'll notice that the nose of the airplane will immediately pitch down, but just slightly.  You'll need to add some power to maintain level flight.  With two notches of flaps, even more power will be necessary to maintain level flight.  The last notch of flaps adds considerable drag, plus even more power.  We don't recommend using this last notch of flaps, as it requires considerable power and slows the plane down rapidly, requiring a very steep approach angle when power is reduced.

For a normal approach, reduce power to about 65% and dial in one notch of flaps.  This will place you in a normal approach configuration, with a normal approach path.  Practice turns in this configuration.  Also practice go-arounds by adding full power, slowly retracting flaps and establishing a normal climb.  Learning how to go-around is important, as it gives you a safe plan should you reject a landing for any reason.

Stalls must also be practiced in the Belite, but they are predictable and gentle.  Be sure to practice stalls at least 1000 feet above the ground.  Start stalls with no flaps; reduce power to flight idle and set up a 45mph glide.  Note the nose position; it will be low in order to maintain airspeed.  Slowly raise the nose and observe the speed bleed off - this will happen quickly.  There will be a slight shudder and the nose (and your seat) will drop as the stall occurs.  Immediately and smoothly, push the stick forward and the plane will instantly start flying again -- it's easy!  Then smoothly add power, and establish a proper climb.  Clean up the flaps, climb back to altitude, and practice some more.  Practice stalls with 0, 1, 2, and 3 notches of flaps, and with power off and with power on.  Note the low kinetic energy, especially with 3 notches of flaps.  In all cases of stall recovery, the nose must be lowered to the correct glide attitude as power is simultaneously applied.  If flaps have been used in the sall, retract them slowly, and transition back to a climb attitude.  Stall training is a great way to learn how the Belite is going to react during the flare to land.

Wednesday, September 15, 2010

Flying the Belite Ultalight Aircraft - Part 1

Editor's Note:

I recently returned from a heavy work schedule and from a great Alaskan vacation! 

My last post was an excellent article by Earl Downs on the Belite.  It provided a great view of the flying qualities of the Belite.

Many people want to know how to transition to flying a single place ultralight airplane, such as our Belite.  This particular post will help you gain that knowledge!  Although originally written years ago by another author, I have been graciously granted (anonymous) permission to update it to reflect our Belite ultralight aircraft.

Enjoy the reading....  Enjoy the learning... and enjoy the flying!

Published in three parts

Flying the Belite Ultralight Aircraft - Part 1

by James Wiebe, CEO
Belite Aircraft

General Flight Characteristics

The Belite 254 / Superlite / Trike (hereafter, collectively referred to simply as: 'Belite') is first and foremost, a very real airplane, requiring competent flying skills to takeoff, fly and land.  In return, it offers a genuine flight experience, with none of the compromises associated with traditional ultralight aircraft and FAR Part 103 legal designs.

Most of the takeoff and landing comments below refer to the taildragger versions -- the Trike version is even easier to land.

The Belite utilizes a standard three axis flight control system consisting of flaperons (ailerons that also act as adjustable flaps, through the use of an ingenious flap / aileron mixer).  It also has a conventional elevator and rudder.

The ailerons and elevator are operated by a conventional control stick, while the rudder are moved through the use of independent rudder peddles.  Any pilot familiar with aircraft such as a standard Kitfox, Piper Cub (or common derivatives, such as the CubCrafter), or Aeronca Champ will find the cockpit to be a familiar and friendly environment.  The flap function is provided by a four position flap lever that intermixes with the aileron control to 'droop' the flaperons.

Additionally, independent mechanical heel brakes are used to both stop and steer the Belite during ground operations.  An optional electric elevator inflight trim system provides for completely neutral flight characteristics during cruise, allowing hands off operation for brief periods of time, such as when taking photographs.  Back pressure is used on the stick in order to maintain a normal approach speed.  All flight controls are lite and very responsive at all speeds.

(For an independent extensive flight review of the Belite, see the excellent article by Scott Severen, published elsewhere on this blog.)

The tail-wheel configuration of the Belite does not present any unusual challenges during takeoff or landing.  The large rudder is very effective and little, if any, differential braking is needed to control the landing rollout.  In fact, customers preferring to fly their aircraft without brakes will be comfortable, especially when operating off of grass airstrips with light crosswinds.

Absolutely no differential braking is needed on the takeoff roll due to excellent rudder effectiveness.  Basic tail-wheel training in a Kitfox, Cub, Champ, Cessna 120/140, Citabria, or other tail-wheel light aircraft should serve to prepare you to handle the Belite.  Differential braking works well to steer the Belite during tax and forward visibility on the ground is unrestricted.  'S' turns are generally unnecessary.

As with the operation of all airplanes, the pilot should be current and qualified.  You should not attempt to fly the Belite unless you would feel absolutely comfortable soloing the airplane you have been flying for tail wheel proficiency.  The EAA can provide help with transition instruction in a taildragger and with 'first flight' issues.  You are encouraged to secure as many resources as possible to help with your transition.

Ground Handling

The Belite utilizes differential heel braking to maneuver the airplane.  The heel brakes will cause the airplane to turn in the direction in which force is applied; left braking makes the plane turn left; right braking makes the plane turn right; braking both sides causes the plane to slow down.

Do not try to turn the airplane from a dead stop by locking a wheel and then adding power.  The airplane will turn much more easily if the plane starts moving slowly first, then applying braking to the appropriate side.  Once a turn is started, the momentum of the turn will tend to keep the turn going.  Once you are taxiing, the rudder alone may be all that is needed to steer your Belite.  As with all tail wheel airplanes, it is a good idea to center the tail wheel when you come to a stop.  This practice will make it much easier to control when you start taxiing again, or when you start your takeoff roll.

There may be circumstances when taxiing in tall grass or on a soft surface that make it difficult to swing the tail when differential braking is applied.  There is an old trick from the day of tailskids that may help out.  If the tail wheel is really bogging down, add sufficient power to get the plane moving, then push the control stick forward (keeping the power up) and then apply brake and full rudder in the direction you wish to turn.  The forward stick will lighten the load on the tail wheel and the rudder will help push the tail around.  Be very careful when trying this, as you could blow a lot of dirt around or upset airplanes behind you.  Always be courteous to other airplanes and pilots.

A note of caution:  one must be very cautious when taxiing in windy conditions.  The light weight and low wing loading of the Belite makes it susceptible to being upset by ground winds.  Unless you have exception skills, fully understand the risks, and (perhaps) have wing walkers available, do not taxi your Belite in winds exceeding 12 knots (15 mph) or greater.  Rapid ground turns should be avoided under all conditions.

Like any airplane, appropriate taxiing technique is important.  The flight controls can be quite effective in helping the Belite ultralight aircraft safely taxi.  When taxiing into a headwind, hold the control stick full back to help keep the tail on the ground.  A tailwind requires to the stick full forward; this will help keep the tail on the ground.  With the quartering headwind, move the control stick into the wind, as if trying to turn into the wind.  With a quartering tailwind, move and hold the control stick away from the wind, as if trying to turn away from the wind.  If the wind is straight over the nose or tail, keep the ailerons centered.  These positions will help keep the wing from being lifted by the wind.

You should be completely comfortable with taxiing, braking, and turning before proceeding to takeoff.  I say again:  have total comfort with ground handling and taxi operations before proceeding to takeoff.

Take Off

Your first takeoff should be made from a runway that is both wide enough and long enough to accommodate errors.  It should also be made from a runway without pressure from other aircraft operations.  Do not make your first takeoff with space restrictions that require maximum performance.  Perform a thorough preflight; make sure that the engine is warmed up and is showing correct temperatures, RPMs, mag checks, etc.

Align your Belite on the centerline of the runway and make sure the tail wheel is centered.  With the brakes locked and control stick held fully back, smoothly increase the power to approximately 75% of full power.  Release the brakes and continue to smoothly increase power to full throttle.  You will immediately see that the rudder is fully effective; you can control direction by use of the rudder pedals.  You won't need to use the brakes.  Keep the ailerons (flaperons) centered.  Directional control on the ground is controlled by your feet, not your hands.

Shortly after applying full power, you can push forward on the stick, and the tail will raise off the ground into a traditional level attitude.  Keep the nose straight (using the rudder pedals), and as the speed passes 40 to 45mph, you'll be able to pull the stick back a little, and the airplane will fly.  Depending on engine power, the total time from brake release to liftoff is about 5 or 6 seconds, depending on field elevation, winds, temperature, aircraft weight, and engine selection.  In a strong breeze, a takeoff roll of well less than 100 feet is an easy matter.

Immediately at and after liftoff, the flaperons become very important.  You'll use the control stick to level the wings.  Concentrate on level wings and a slight climb attitude.  I enjoy climbing to the top of ground effect (about 30 feet off the ground), then briefly leveling off and continuing climbout at a stabilized Vy speed, which is about 50mph.

As you gain more experience with the thoroughly enjoyable takeoff characteristics of the Belite, you will find that it also takes off very well in a three point attitude.  The basic procedure is the same, but instead of pushing the control stick forward, you simply place the stick in a centered, neutral position.  The Belite will fly off the ground when it is ready, in a tail low attitude.  Make appropriate minor pitch adjustments as required to establish a climb.

Don't climb out too rapidly -- never climb out below Vx (about 40mph); if your density altitude is high, or your weight is heavy, your climbout speed should be at Vy or higher.  Remember, you are flying the airplane.

Continue to Part 2 by clicking here