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.

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