(^44) Reach for the sky
Power and position
“This may be the first time you’ve ever
had to add power, then take off power
again on the runway,” Murray had
said earlier. “Your brain may have a bit
of a problem with that. It’s because the
lead plane is doing a reduced-power
take-off to allow the other planes to
have the flexibility of excess power to
maintain position on them.
“On take-off and landing, how
do you know what your airspeed is
if you’re the aeroplane following?
You don’t know. Number One will
set the airspeed, you have to trust ...
and keep trusting. If the aeroplane
in front of you rotates and looks as
though it wants to fly, you can be
damned sure that yours will as well. ”
He was right: it was weird and
somehow just wrong. As we rolled down
Lilydale’s 18R in echelon right, I needed
to pull the throttle back to make sure
we didn’t put prop marks in PTM’s
elevator. My brain had a huge problem
with that, conditioned as it was to use
max power in the take-off roll!
But that was nothing to what
happened to my grey matter on climb-
out. With a sou’ wester bobbling us
around, I edged ECI away from the
leader to add safety space, only to
be encouraged to close-up the gap
or I’d never get into position. It was
my first exposure to a formation
basic that would plague my first few
attempts: staying in position is a
matter of managing the energy in the
aeroplane via pitch and power.
A good formation is inch-perfect,
and the secondary effects of the
controls can be enough to put you
somewhere you don’t want to be, so
you have to counter that with another
control input. For example, if you
need to gain speed to catch up, you
throttle on, but the secondary effect is
an insidious increase in height, which
will have you out of position again.
Therefore, a power increase must
go hand-in-hand with forward stick,
which in turn helps you with the
speed to get into the right spot relative
to the lead aeroplane. But here’s the
tricky bit: you don’t know how much
to compensate, and finding that out is
a matter of practice.
And trying to hold station was
a matter of constantly moving the
controls; not a second ’s rest and don’t
even think about re-trimming! And here
was me thinking we were going to cruise
along leisurely behind the leader ...
Where we were supposed to be
was in echelon right–about 45o
off the starboard tail–but with me
frantically juggling the Airtourer’s
controls we were all over the place
like a scarf in a slipstream.
“The best way to define a position
line in echelon with most aeroplanes
is the wheels,” I remembered
Murray telling me. “You overlap
the nosewheel with either the left
or right main wheel depending on
where you are in the echelon, and
that will give you the position. Later
on you can adjust it a little bit, but for
learning, it’s a good starting point.”
It sounded so easy in the briefing,
but was going to remain a theory
until I got the hang of using throttle
and elevator in unison.
But without doubt, the freakiest
part was flying around the sky
having no idea where you are, or
indeed what’s ahead of you. To fly
formation, the trailing pilots have
to delegate operational safety to the
leader and trust they will navigate
the whole formation back to base
without trimming any trees en route.
As I said, freaky.
Line Astern
“When you move from the echelon
to line astern, you back off the power,
push down, pedal her across and bring
the power back on when you’re about
one third of the way across, then raise
the nose again to the right spot.”
If I could co-ordinate that I’d be
making good money as a one-man
band on a street corner!
Murray’s instruction was, however,
based in sensibility, and I would have
to get used to this tricky move. The big
danger with moving into line astern is
that you will cop the wingtip vortices
and prop wash from the leader as you
go, so in the move you swing under
them just like you were ducking under
a rope fence. That’s the reason for the
elevator. The power loss is about not
letting your aeroplane gain speed when
you push forward on the stick. Back off
too far, or bring the power on again too
late, and the leader will escape and you
may not have the excess power to catch
them up quickly.
And here’s some experience talking:
if you push down first and don’t back
off the throttle, you’ll end up so close to
your leader’s belly that you could reach
out and clean it with a chamois (which
inevitably it will need doing).
When in position, the trailing
aircraft is actually lower than the
leader, even though it often doesn’t
look that way from the ground. To
be at the same level is to court all
sorts of tumbling air spewing out
behind the leader Naturally, Murray
has ideas for avoiding that.
“The way we do it is to use the
black section of the walkway along
the wing,” he said. “When you look at
the trailing edge from behind, you’re
trying to position yourself so that the
black walkway makes up 50% of what
australianflying.com.au
AUSTRALIAN FLYING March – April 2015
The freakiest part was flying
around the sky having no idea
where you are ...
Line astern. Notice the step-
down position of ECI to avoid the
propwash coming from the CT4.
john hannent
(John Hannent)
#1