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been taken up. You will increase
hover height slowly, until the strain
is taken, with the loaders guiding the
strops as necessary, taking care to be
free to move away quickly should
the need arise. At all times if an
engine fails, ground staff must move
in the opposite direction that the
helicopter would go, e.g. JetRanger
to the right, staff to the left, or the
opposite for an AStar (it depends
which way the blades rotate). They
should not turn their back on the
load, or get directly underneath it.
Neither should they wrap lines
directly around their wrists or
bodies. When finished, they should
clear the area as soon as possible.
As you take up the weight and the
rope stretches, the difference in
performance will immediately
become obvious—it will feel as if
you're attached to a large rubber
band. Once you're hovering, and the
marshaller is sure the load is clear
(and you are sure you can lift safely,
flashing the landing lamp once to
indicate this), the marshaller should
check behind you for other aircraft
and give the affirmative signal, as
you will find it difficult to do a halfturn
to check for yourself. Keep a
close eye on your Ts & Ps at this
point – if you don’t have a power
reserve, the load is too heavy and
you will have less control at the
destination.
The machine will feel quite sluggish,
as if it's tied to the ground. Move
forward slowly, giving due regard to
the load's inertia, not alternately
slowing down and speeding up, or
you will confuse it. Rather, move
forward and keep going to allow the
load to follow, which sometimes
takes a bit of courage, to see how it
flies. Make all control movements
smoothly and evenly. Don’t allow
the load to sink, as, if it hits the
ground it will trip you. The torque
used now will give you a good idea
of what is needed for landing, so be
careful if you are going to a higher
altitude (it reduces at about 2-3% per
1,000 feet in a 206).
Once in flight, remember that the
load is the part that should be kept
straight and level, not the helicopter,
and keep away from anything
underneath that could be damaged.
Only with imminent danger to the
aircraft should a load be jettisoned,
usually from excessive swinging. As
a point of interest, 10 gallons of fuel
from 500 feet will go straight to the
basement of a 3-storey house.
Load Behaviour
Every load has its own VNE, usually
only found by experiment, which is
why you should always start off
slowly and build up to a point where
it starts to give trouble, then back
off. Most helicopters will carry loads
at quite high speeds, but the load
itself might not be able to handle
it—a sudden input of drag when
something falls off could become
quite a problem. Although
customers don’t like to pay for
unnecessary flying, there’s no rush.
Take it easy.
372 Canadian Professional Pilot Studies
External loads increase the frontal
area of the whole aircraft, which
naturally increases drag, so you will
need more power overall. A load
may be easy to lift, but present
enough drag to cause severe
difficulties, particularly where you
reach power limits too quickly to
maintain forward flight, and the load
overtakes you and pulls you along. A
long-line (see below) needs more
anticipation, so you need a high
degree of co-ordination and
patience. It's not the sort of thing
that can be learnt in any other way
than by having lots of practice.
Loads with an uneven shape will
tend to spin and, if they're slung
without reference to their centre of
gravity, could tip over. A drogue
chute can stabilise them, but use a
windsock type rather than a pure
parachute, which will bounce around
trying to spill the air out. Naturally,
these must be kept away from the
tail rotor. Logs or cut timber usually
fly poorly unless a tail is installed,
which can be made out of a bough
or piece of plywood, sticking out of
the back.
Oscillation or excessive vibration
can come from a number of places,
usually a combination of the stability
characteristics of the load and
forward speed. Heavy or dense
loads, such as bags of cement or
drums of kerosene, will not usually
present problems due to their mass,
but large-volume loads of low
density can oscillate at a certain
critical speed, again usually only
found by trial and error. You can
　
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