Global Aviator May 2018 / Vol. 10 / No. 5 55
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Piston and Turbine Helicopters up to 5 700kg
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Hangar 44, Gate 5, Lanseria International Airport P.O. Box 43, Lanseria, 1748
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E-mail: [email protected] Reg. CK No: 2010/174526/23 VAT no: 4410261319pick them up fairly quickly.
What about the transition from
forward flight to the hover? The
converse is true here – they are quite
easy to explain but a lot harder to do.
Basically, at around 500 feet
above the ground the pilot selects a
landing point. He or she then keeps
that point at a specific position
on the windscreen, raising or
lowering the collective as required
in order to maintain a constant
angle of approach. In fact, this is
very similar to the technique of a
fixed-wing approach to landing.
The difference in a helicopter
is that you slow down before you
land. This is something I’ve always
liked about helicopters, as it gives
you lots of time to think and decide
exactly where you want to land.
The deceleration is done
gradually, from around 300 feet
above the ground, by noting the
apparent groundspeed, and keeping
that the same as you descend.
In practice this produces a
gradual slowing down of the aircraft.
Then at about 100 feet you simply
look ahead and come gradually
forward and down to a normal four
foot hover. As you decelerate, more
power is required for hovering.
Also, careful pedal work is
required, and this is what students can
find quite difficult. In addition they
have similar difficulties to fixed-wing
students in learning to fly a constant
angle approach to the correct spot.
However, I would say that, overall,
helicopter transitions to the hover are
far easier than fixed wing landings
... and I’ve learned to do both.
Helicopter pilots do need to
be careful of certain factors when
transitioning from forward flight
to the hover. If they are going too
fast, the helicopter could get out of
control when close to the ground,
which is clearly not a good idea.
It is even more dangerous to be
high and slow. A helicopter which is
descending with very low airspeed
and power applied can get into a
dangerous aerodynamic condition
known as ‘vortex ring state’ when
the aircraft can literally fall through
its own downwash and crash.For this reason students are taught
to go around if too high and slow
on approach, or too low and fast.
Contrary to what many people seem
to believe, helicopters are not quite
magic carpets which can do anything!
That is a necessarily brief
explanation of helicopter transitions.
The terminology has often caused
confusion, and when the rules for
passenger carrying for PPLs in the
UK were first formulated and stated
the need to have “carried out three
take-offs and landings within the last
90 days”, helicopter private pilots
were delighted, as this literally meant
that they would have to simply lift the
helicopter off the ground and put it
back down three times. Needless to say
this was not how it was meant to be.
The wording for helicopter
pilots was hastily changed, and is
now different, and the PPL(H) has to
have flown three circuits – in other
words done three transitions – to
be current to carry passengers. This
simply proves what most of us have
always known – helicopters are rather
different from other flying machines. •