how to fly a helicopter
A helicopter creates lift
in a different way. Where a fixed wing aircraft has to be moving to
produce lift by the "plane" or angle of attack on the wing, a helicopter
achieves it by manipulating the main rotor blades, changing the angle at
which they meet the air and subsequently the angle of attack. The drawback
with this setup is the need for torque control with a tail rotor, which
bleeds power from the engine every time it's used. That becomes a factor
when you start getting into advanced manoeuvres.
The collective control is the lever to
the left of your seat mounted on the cabin floor. Moving the collective up
or down is what creates pitch change in the rotor blades, causing you to
climb or descend.
You must use one hand on
the control lever that is at your side (the collective control stick) to
raise or lower the helicopter, while at the same time controlling the
throttle (not an easy task).
This is a control which is only found in helicopters and is linked to the
engine power. Moving this up and down changes the pitch of the main
rotors. As the pitch is increased more power is required from the engines
so that the rotor speed is kept at the same level.
The cyclic control is the
actual "stick." It tilts the main rotor assembly through 360 degrees,
allowing forward, backward and sideways flight.
You must use your other
hand on the control lever that is just in front of you (the cyclic control
stick) to move the helicopter forward, backward and to either side, as if
you were in a conventional aircraft.
Moving it forward or back will point the nose of the helicopter up or
down. It does this by varying the angle of the rotor blades as they go
round, tilting the rotor back and forth. When moved left or right the
rotor tilts in that direction and the helicopter banks and rolls.
And finally you must use
the tail rotor pedals, on the floor, to control the pitch of the
tail-rotor. For straight flight, the pitch of the tail rotor is set to
prevent the helicopter from turning to the right as the main rotor turns
to the left. The pilot pushes the left pedal to increase the pitch of the
tail rotor and turn to the left. Pushing the right pedal decreases the
pitch of the tail rotor and turns the helicopter to the right.
control is a 'twist-grip' on the end of the collective lever and is linked
directly to the movement of the lever so that engine RPM is always correct
at any given collective setting. The pilot only needs to 'fine tune' the
throttle settings when necessary.
Controlled with pitch - While maintaining altitude, move the cyclic to
change the airspeed. This requires a little coordination, similar to the
throttle and yoke in a fixed wing. In level flight you increase
collective/move the cyclic forward to speed up, reduce collective/pull the
cyclic back to slow down. As you approach your desired speed, you have to
adjust the collective to maintain it. It's a good idea to practice since
you'll do this every time you take off or land.
Controlled with power - Pull the collective up to increase climb rate,
lower it to increase descent rate. This is combined with cyclic movements
to produce constant speed climbs and descents or level flight. While at
cruise altitude and power, any minor altitude adjustments can be made with
the cyclic only.
Helicopters are highly sensitive to
input and very responsive. Slight pressures are required to master the
finer techniques in hovering and landing.
Most helicopters have no
form of adjustable trim. For example, if you pitch down when levelling off
from a climb, the aircraft will continue descending unless you make an
opposite cyclic input from the neutral position. Once you've levelled out,
you need another input to take out that correction. This characteristic
applies to forward, backward and sideways flight, and on a smaller scale
in a hover.
Performance in any "mode"
will be more responsive to input. Whereas a fixed wing may become sluggish
and hard to control at slow airspeeds a chopper stays just as responsive
if not more so.
Power reductions require
some attention. The main rotor blades are your only means of creating
lift, so if you drop the collective completely there's nothing holding you
up, even though the throttle is wide open. All helicopter pilots are
taught to "glide" the helicopter with little or no power to the ground. A
little known fact (much like those seeds that fall off trees- "twirlybirds"
I think kids call them) is that a helicopter will still "fly" or glide by
the simple fact that the blades will spin on the way down. The landing may
be hard but as you will see not impossible.
Winds and turbulence play
a large role in how you control and master the dynamics. Much as a fixed
wing takes off in the direction of wind so too should your chopper.
One of the things that
remain constant in fixed and non-fixed wing aircraft is that in a turn you
loose altitude and go nose down without correction. This doesn't apply to
"side" stepping in a hover.
takeoff is performed in the following fashion. First, you
must make sure the throttle is all the way
open (For a turbine powered helicopter,
advanced properly for a reciprocating engine
powered helicopter). Once you have
established the proper operating RPM, then you
can pull up slowly on the collective. As you
increase collective pitch, you need to push
the left pedal (In American
helicopters...right pedal for non-American
models) to counteract the torque you generate
by increasing pitch. (In reciprocating engined
models, you will advance the throttle as you
increase collective pitch). Keep pulling in
pitch and depressing the pedal until the
aircraft gets light on the skids. You may
sense a turning motion to the left or right,
if so, you may need more or less pedal to
The cyclic will become
sensitive and (depending on how the aircraft
leaves the ground heels or toes of the skids
last) as you continue to pull in pitch and
depress the pedal, you will put in the
appropriate cyclic input to level the aircraft
as it leaves the ground. As the aircraft eases
into the air, forward cyclic will be required
to start the aircraft in a forward motion. As
the aircraft advances forward, it will gain
speed until about 15 knots and then the
aircraft will shudder a little as you
transition through ETL (Effective
Translational Lift...See the unique forces
page for a more in depth explanation of ETL).
As you transition through ETL, the collective
will need to be reduced, the pedal will need
less pressure, and the cyclic will need to be
forced forward to counteract the force against
the front of the rotor system.
push forward will result in an abrupt nose
high attitude and a reduction in forward
speed. After the shudder of ELT is
experienced, you will see a marked gain in
forward airspeed, a reduced need for pedal
input and a reduced need for collective pitch
as the rotor system becomes more efficient.
The airspeed indicator will most likely jump
from zero to 40 knots indicated airspeed and
will smoothly advance as the aircraft goes
faster. Now you have taken off and with a
little release of forward cyclic pressure, the
aircraft will establish a climb and continue
to gain airspeed. At this point, the pedals
are only used to trim the aircraft, and most
manoeuvres are accomplished by using a
combination of the cyclic and collective
The largest error made by new chopper
pilots is to "over-control". That means making control movements that are
out of proportion to the corrections required. It's common in the
beginning and keeping corrections small but immediate is important. Cyclic
and tail rotor movements affect each other and precision is impossible if
you're heavy-handed. So before adding collective, the cyclic should be in
the neutral position. Otherwise you'll start moving the second you leave
the ground. If you lift off with things centred you can devote more
attention to heading and drift. You're less likely to have to make big
Over airports and flat ground you
won't go wrong using the numbers in the pilot operating hand book. Climbs
and descents over rough terrain generally don't work with those speeds -
out of necessity they tend to be slower, and climbs tend to be steeper.
There are a few things to watch in a steep climb. Try to maintain at least
15-20 knots indicated airspeed. Depending on the altitude, slowing to zero
in a climb can result in an unplanned descent, and below 20 knots speed
bleeds off quickly. Add collective carefully and don't exceed the limit of
the yellow "max continuous power" range on the torque gauge.
A big selling point of
helicopters is that you can land in your backyard. Where then would be the
best place to learn to hover? An airport with a 12,000' runway and a
7,500' crosswind runway. You want a lot of open space where you're
guaranteed not to hit anything. You want somewhere that neighbours won't
complain about the noise. You want somewhere with long sight lines to the
horizon so that you won't concentrate your gaze in too close. You want
somewhere that you can get fuel when you run out. All roads lead to the
big airport! Generally the tower and ground controllers will give you
permission to practice hovering on whichever runway isn't be used that day
and/or over a seldom-used taxiway.
Most instructors will start by giving you one control at a time. You take
the antitorque pedals and they handle the cyclic and collective pitch. You
practice pedal turns. Then you take the collective while the instructor
controls the cyclic and pedals. You go up, you go down. Maybe you land.
Then you take the cyclic and the instructor takes the other controls and
... 1 second later the helicopter is oscillating like crazy and you hear
"I have the controls" in your headset. Any good instructor will alert you
to the fact that you need to be very light on the controls: "you fly with
pressures, not movements." The instructor will also tell you that there is
a bit of lag between the time that you put in a control input and the time
that the helicopter reacts. What most instructors won't tell you is how to
deal with these facts.
Here are a few tips for handling the cyclic, which controls forward/back
and left/right movement of the helicopter:
Focus your gaze at least
1/2 mile in the distance if the sightlines in your practice area are long
As soon as the helicopter
is handed to you it will start to drift to the right. The tail rotor is
counterbalancing engine torque but at the same time is pushing the
machine to the right. Expect to hold a little bit of left pressure on the
cyclic to avoid this translational drift.
Don't put in and hold a
control input pressure. Suppose the helicopter is moving forward a bit.
You press back on the cyclic and hold that pressure. One second later the
helicopter has responded to the initial pressure by arresting its forward
creep. One second after that the helicopter has responded to two seconds
of continuous pressure by rushing backwards at a frightening clip. If the
helo is moving forward, press backwards for a split-second then try to
return the cyclic to a neutral position. See if the helicopter stops
creeping. If so, great. If not, try another little stab of back pressure.
Although every second or two you are doing something with the cyclic, in
any given instant you need not be putting in any cyclic input. Nudge the
cyclic and then return to centre. Nudge and then return.
After an hour or two the
instructor might be doing more harm than good in handling the other two
controls. Everything is cross-coupled so if he is messing with the
collective or the pedals it will require you to take action with the
cyclic. It is actually easier to handle all three controls because at
least the machine isn't doing completely unpredictable things from your
point of view.
Take a break every 20
minutes by practicing takeoffs, trips around the pattern, and approaches
One of the keys to a good approach is
maintaining visual contact with your landing area. It's impossible to
adjust your descent rate correctly if you lose sight of it. Sometimes this
means turning the nose slightly with the tail rotor to keep things in
view. That comes with practice. Think of the approach as you might in a
fixed wing by imagining a glideslope and a touch point that you want to
Plan on being at about 200-500ft.
above ground or obstacles .5km from the landing area. Try to gauge your
rate of descent by a reference on the ground. If you reach this target
altitude early, hold it until you reach about .2km from the landing area.
With your first couple of tries remember to keep an eye on your airspeed.
it's very common for pilot in training to overshoot the landing area.
Slow to 40 knots 35-37%
at about .2km from the landing area and begin to slowly descend. Things
will start to happen fast. Check your descent rate. It's very important
that you don't let your vertical speed get past 300' per minute - adjust
power as required. Obstacles permitting, you want to be roughly as high
above ground as the width of the rotor blades when you arrive at the edge
of the landing area. As you get closer and closer to the edge, gradually
slow to 30, then 20. You may loose sight of the landing area briefly while
bringing the nose up to bleed off some of that airspeed. Whether you're
descending or not while doing this, you'll still have to carefully
coordinate pitch and power. Next to hovering, that's probably the biggest
challenge of the approach. I
As you cross the edge
of the landing area, you should be levelling off and continuing to slow
below 10 knots. You may have to reduce power slightly and bring the nose
up to do that. Watch the ground to ensure you remain moving forward as you
drift into position. When the exact spot you want to land on appears to
slide beneath the nose, you'll be in a good position to reduce collective.
Make sure your parking brake is armed.
Ease the cyclic back to
bleed off any remaining momentum, then ease it forward again to level the
attitude indicator when all forward movement stops. At the same time if
the rate of descent is too much add some collective. Now it's just a
matter of keeping an eye on drift and getting the wheels to make contact
with the ground. Keep your rate of descent as low as possible. Have the
Parking brake armed and reduce all power.