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quite suitable. Items should be
carefully and evenly stacked in the
centre, with the net stretched round
the load on the ground before
pickup. Individual light loads, such
as jerrycans or containers, ought to
be lashed together, since the net may
not completely enclose them at the
top. If there are many small items,
consider a tarpaulin as a liner, which
will stop them falling out. Be aware
that lifting points already attached to
anything may have been designed for
cranes, which don’t, as a rule, fly
sideways or get caught in
updraughts, etc.
The weight of each load should be
known, with sand and stuff kept dry
and, if possible, weighed
immediately before loading, as a
good soaking will increase the weight
dramatically and give you a surprise
when you lift it. What happens most
often, however, is that the guys just
bundle stuff into a net, and as long
as you don’t overtorque the machine
you’re OK. Although convenient,
and mostly used for nets, a singlepoint
hookup is not always the best
plan, particularly for short loads, and
should only be used on loads
designed for it, with a swivel, to stop
the line unravelling. You also need
to be particularly careful about the
load’s C of G, or it may tip and start
rocking, so keep the heavy end
down. The shorter the cable, the less
the tendency to swing.
26 The Helicopter Pilot’s Handbook
For a single pole or log, wrap the
rope or chain twice around the end
of it and carry it vertically (steel rope
grips best):
A 2-point sling is a common
method for long loads, such as drill
collars, pipe stems, lumber, etc:
The ideal angle would be 45°, since
the weight is then taken evenly on
each strand with the least stress. In
those circumstances, a 400 lb load
would have a strain of 200 on each
side. If the central angle becomes
120°, it doubles, and at 150°, it's 800.
Double-wrap the cables, and maybe
slip some wood between them and
the load to stop them slipping.
Three-point hookups are not
common, and are usually for loads
designed for them, but boats are
lifted this way. 4-point slings, on
the other hand, are quite common
and used for box-like loads, attached
to each corner—where the sling may
catch or damage the load, use
spreader bars to keep the rope away,
as well as for stability:
Beware of loads with a high C of G,
as they may tip over.
Tag lines (short lines underneath a
load) are for loaders to grab on the
setdown. They should have a safety
latch and be heavy enough to stop
waving about, but long enough to
catch if the load is swinging too fast.
Argos and Quads can be moved
with strops underneath. Just wrap a
strop around the Quad engine,
ensuring it goes inside the pedals (or
they will get bent). Then choke it
and attach it to the hook.
Personnel briefing
All concerned should be aware of:
· The hook-up
· The setdown
· Hand signals
· Proper use of radios (i.e. don’t
hog the airwaves)
Specialised Tasks 27
· Direction to move in case of
engine failure*
· Not standing under the load
· Number of trips between
refuelling stops
· Retrieving slings and nets
· Use of protective equipment
· Accident procedure
*This depends on which way the
rotors spin. With North American
rotation (anticlockwise as viewed
from above), the helicopter has a
natural tendency to drift to the left
when the engine stops, so ground
crews should always work to the
right of the helicopter and be
prepared to go that way if they think
anything untoward is happening.
Astars go to the right.
Hooking Up
Ground crew are nice to have, but
you often have to do it yourself:
Note: Always lay it out in front!
If you have one, the marshaller
should be at least 25m from the load
with his back to the wind so you can
see him from your high position. If
he needs to change places, he should
cease marshalling first, so he doesn't
move backwards into unseen
obstructions. Using standard
marshalling signals, you will be
positioned over the load, where the
loaders apply the static discharge
probe to the hook and place the eye
of the net or sling inside it.
As mentioned above, loaders should
always work to one side of the
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The Helicopter Pilot’s Handbook(17)
