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INITIAL FLIGHT TEST
As new VariEzes emerge from
their concealed assorted construction sites and start taking to the air for the first
time, the great majority of the pilots report no problems, "the aircraft flew great,
just like the book". However, a few are still having control problems during initial
flights. When we investigate the problems we often find a pilot who is neither current,
proficient, familiar enough with the VariEze owners manual, or does not understand that a
VariEze does not fly like a Cessna 150 or some other sluggish trainer. The VariEze is high
performance responsive aircraft with differences. It has a side stick and the pilot should
keep his forearm on the armrest and use his wrist to control pitch. Also, the rudders can
both be inadvertently deployed at the same time and the pilot should be careful not to do
this in flight. Jim Davis got a little tense and unknowingly pushed both rudders
simultaneously giving him yaw-roll problems.(see his story below). Another pilot reported
very poor climb, and he said that he almost hit a small hill on his first take off. I was
concerned until I found out he was holding 130 mph, thats 38 mph above best climb
speed, no wonder the climb rate was low. The nose and canard attitude gave him the
impression he was climbing when he wasnt. I flew first flights on two new
VariEzes here at Mojave. Both aircraft flew normally, but both pilots had problems
when they first flew on their own. One pilot rounded out high, got real slow on landing
and hit the winglets on "crunch-down". The other pilot had pitch control
problems (PlO) and damaged the nose gear. He was trying to fly with his whole arm instead
of just the wrist.
Lets discuss the three common areas that seem to give a few people problems.
1. The non-standard rudder pedals. Beware not to push both at the same time in flight. One will usually be out more than the other producing unwanted yaw. The VariEze rudders are very effective and the yaw generated couples easily to roll. In fact the roll rate will almost double with rudder added to aileron control. Adjust the pedals so your foot does not press the pedals naturally.
2. Pitch over-controlling. The novice pilot will expect the VariEze to handle like the C-150, or whatever he last flew. The experienced pilot knows that J-3 cubs and Bonanzas handle different and will make the transition easily. Spend enough time on the runway just above rotation speed but below lift-off speed and practice controlling pitch so you can put and hold the desired/selected pitch proficiently. Hold the forearm on the arm rest and control pitch with the wrist only. Do not over-rotate! The highest rotation you should see during this or the later flights is the canard up to, but never above the horizon. Better yet, keep it always at least 2 degrees below the horizon.
3. Nose high, Slow touch down speeds. To avoid this be sure that during take off and landing to not rotate the nose above the horizon. On take off rotate the nose/canard to just below the horizon. Hold it there and wait for lift off. On landing, fly final and touch down while you can still easily see over the nose. If you cannot see the runway, go around and use more speed next time. You will find that using this technique you will be a little above the minimum touch down speeds. This is okay to be a little fast for your first few landings. Runway length notwithstanding a hot landing in a VariEze is no problem and is much better than a slow, wing rocking, blind "arrival".
The following is from Jim Davis about his first flight experience:
"On first flight, I experienced unusual roll on climb out and level flight. This occurred unexpectedly, both right and left at a random rate. First landing was exceedingly hard and resulted in damage to the main gear, wings, etc. I believe this was due entirely to pressing on the rudder bars inadvertently. I had flown back seat of another VariEze and experienced the unusual sensitivity of the controls. However, this didnt carry over well to the rudders which I had been tromping on for brakes during two hours of high speed taxiing. Rudder cable length was short, cut to insure solid brakes with toes down. Seat cushions, adjusted to other Rutan criteria definitely accentuated the problem. I didnt realize the unusual roll induced in swept wings by rudder action. Suggestion: Make sure your rudder cables are long enough to keep foot pressure off rudder bars without any effort. Make every effort to ride the backseat of another VariEze before first flight in yours. Fly dual in a Thorpe T-18 or other small plane with very sensitive controls and speed on final of 80 mph. There is really no substitute for this experience - and keep your feet off your rudder bars unless you want yaw and plenty of roll.
Jim Davis, Falls Church, Va
Another area we need to emphasize
is weight. During the initial flight testing "KEEP IT LIGHT." Our philosophy is
"if it isnt needed for first flight dont put it in". Give your
aircraft every chance of successfully completing the test phase. If you keep the weight
out of the tail (gen/alt/starter/pump etc) you dont have to ballast the nose as much
to get the cg into the "first flight box". Remember the aft cg limit might not
be the same for your aircraft as it is on N4EZ due to builder differences. Be careful,
work toward the aft cg limit gradually.
Another question is "why wear a parachute during flight test?" Will I hit the prop or the canopy or should I slow up and roll inverted - - ? Remember your aircraft may not fly like N4EZ or a builder error could cause destructive flutter or a loose fuel line could cause a fire, or many other things. In any of these cases the parachute is the only means of survival. As for how to bail out - - - - - you open the canopy unfasten the belt and jump over the side. Dont worry about the prop, you will fall away from the aircraft long before you get blown back into the prop. You need 25O+kt before prop contact should be a factor. Remember if you find yourself in a situation where staying with a stricken aircraft means death and the parachute is a chance to live, I think I would take that chance no matter what the odds were. It sure is comforting to have a chute on your back to get home with in the remote chance the aircraft came apart. As a two-time member of the Caterpillar Club, I recommend parachutes enthusiastically. (Above comments by Dick Rutan) -