Rans S-12, Руководство по эксплуатации для пилотов

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The Falling Leaf Maneuver
A falling leaf maneuver can be done by an advanced pilot provided there is sufficient altitude
to recover from an unwanted departure (spin). Remember this plane is prohibited for inten-
tional spins and if you are uncomfortable with your ability to keep the plane out of a spin, then
don’t do a falling leaf. It is a mildly violent maneuver and does cause some significant stress
on the airframe, thus should not be a regular maneuver or one that an amateur pilot toys with.
Bring the nose up and add a slight amount of power (2500 or 3000RPM), keep the stick nearly
full back to keep the plane in a stalled attitude. Use the rudder pedals to maintain directional
control by “stabbing” them with your feet. DO NOT push a pedal down and hold it down. If
the plane banks left, stab the right rudder and immediately release it, then be prepared for stab-
bing the left rudder. This maneuver can quickly accelerate into a spin with improper use of the
rudders by the pilot. If you loose positive control of the falling leaf maneuver, immediately
push the stick forward and recover from the stall. It will take a lot of practice to learn the
ability to “predict” which rudder pedal to push and how hard to push it. Falling Leaf is more
magical than it is aerodynamically balanced.
Spins and Spin Recovery
While the S-12 is prohibited against intentional spins, it is the test pilot’s best recommendation
to follow this technique to recover from unintentional spins:
1) throttle to idle and let go of the stick (or stick to neutral)
2) retract flaps (if extended)
3) apply rudder full opposite the direction of yaw
4) push the stick forward the amount necessary to unstall the wing
5) recover from the dive with no more than a 4G pull-up
Though not tested on N6167U, recovery from an unintentional spin using the above procedure
should yield prompt and decisive control of the situation.
Lazy Eights and Chandelles
While they were performed in the flight testing phase, these maneuvers are not recommended
in the S-12 until the pilot has had some aerobatic training. The S-12 is a fragile aircraft and
for the most part, if you are very aware of airspeeds and G-forces, you can execute some rather
enjoyable chandelles and lazy eights. However, a low time pilot with no understanding of
aerobatics may be quickly overwhelmed with either maneuver and inadvertently overstress the
aircraft. Use common sense when approaching these maneuvers.
Rough Field Operations
The Rans S-12 Aircraft is equipped with what the factory calls “tundra tires”. While they do
allow the airplane to operate from soft and rough fields, they do not indicate that the airplane
is well suited for this type of field. The particular concern with rough fields is the nosewheel.
For example, after touchdown on a rough field, it is better to taxi the remaining distance
required at 30mph with the nose off the ground than it is to taxi at 5mph with the nose on the
ground. It will take only one rough field operation to make the pilot aware of this, there is
a great deal of noise coming from the nosegear on rough fields. The rough field procedure
begins far before touchdown. Use full flaps to get the slowest touchdown speed and attempt to
hold the plane 2 inches off the runway until it settles down. Use as much back pressure as nec-
essary to keep the nose off the ground. Similarly on take-offs, the pilot should hold in FULL
back stick until the nose comes off the ground, then only use the amount of pressure required
to keep the nose off the ground. Use two notches of flaps for rough field take-offs. Three
notches may provided a ‘lighter’ feel but requires some special skills and is for the advanced
pilot. Engine failure near the ground with full flaps in a nose high attitude will result in a very
hard landing. Force the airplane off the ground as soon as possible and then fly the airplane
in ground effect until it accelerates to an acceptable climb-out speed. Steep climbs at low air-
speed with flaps extended should be avoided in all but the absolutely necessary cases.
Short Field Operations
Short field landings are about 30 to 40 percent longer than they need to be because of the inad-
equate braking system. Even with poor brakes, the S-12 can be comfortably operated in most
any condition on a 1000ft runway. Although at the time of print, this aircraft hasn’t been tested
at gross weight on a hot, humid day, the test pilot can comfortably report that 1000ft is enough
distance (even on a grass runway) to takeoff and land over 50 foot obstacles, provided the pilot
is of moderate skill. In many cases, with a skilled pilot operating at 3000 feet density altitude
and without a passenger on board, 500 feet of runway is comfortably sufficient, provided the
50 foot obstacle does not have to be cleared. For a short field take-off, use two notches of
flaps. An alternate technique for short field lift-off is to use three notches of flaps but this is
kind of an extreme measure and can lead to an accident if things go wrong. Hold the brakes as
hard as you can and run the power up to where the airplane is barely able to stand still. Then
quickly release the brakes while at the same time pushing the throttle to full power. Keep the
elevator essentially in the cruise setting for the most aerodynamic takeoff roll. If it is a rough
AND short field then keep the elevator horizontal until you reach 20mph and then briskly and
gently use it as necessary to get the nose off the ground. After the aircraft leaves the ground,
climb at the best angle of climb speed of 40mph. When you are clear of your obstacles (if
any), continue the climb at a safer speed of 65mph and retract the flaps slowly.
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