THE HISTORY OF V.A.R.M.S The Annual Diary 1990 - 2009

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3. Greaser: No description required here, as we all know what a greaser looks like,
right?
Well, you know what’s going to happen now, don’t you? Some git is going to tell you how
to fly... don’t you just hate it when that happens.
Getting a model from a particular point in the sky down to a particular point on the ground
is basically an exercise in energy management. At 100 feet you model has a given
amount of potential energy compared to its resting state on the ground. Looking at the
extremes of your many choices of action, you can dive vertically downwards converting all
that energy into velocity, or you can burble around on the stall trying to retain height by
energy conservation instead. Neither is a wise choice of action, instead, this is where the
circuit comes into play. The idea of flying a circuit is a simple one, as the pioneer aviators
at the turn of the century found out; this simple pattern gives you the time and the
opportunity to adjust your glide path (which is determined by balancing speed, height, drag
and direction), so that you arrive at threshold with just the right amount of remaining
energy to pull off your high quality landing. As I mentioned before, without flight
instrumentation we are going to have to rely on judgement to balance the factors involved,
and good judgement can only come with practice.
What happens with practice is that some hidden part of your subconscious becomes a
computer, it automatically correlates what the eyes see with the knowledge database that
you have build up from previous experience, This will vary from model to model and will
be refined with experience, the critical factor being the behaviour of that particular wing
section upon which your model is relying. The other critical factor is the efficiency or
otherwise of your glidepath control apparatus, the airbrakes/spoilers living in the wings.
So to recap, you control altitude and airspeed with the elevator, drag (and also airspeed)
with the spoilers.
Traditionally a circuit is square in shape; you fly overhead into wind passing to a point
somewhere in front of you where you will commence your first crosswind leg, either to the
right or left as the situation dictates. At the appropriate point you turn another ninety
degrees in the downwind phase, losing altitude as necessary, The point at which you
enter your final crosswind leg, known as base leg, is crucial, as it will determine the
amount of energy you have left when you enter the last into-wind leg, known somewhat
sinisterly as Finals. If you turn too soon you will come over the landing area too high and
with the distinct possibility that the brakes may not be man enough to kill off the excess
energy. If on the other hand you turn too late, you will find yourself short of the required
energy to reach the landing area and that’s usually when the lurking fence leaps up and
takes a bite out of your sailplane. The square approach is the simplest and best way to
give you the time you need to sort things out and bring your flight to a suitable and
satisfactory conclusion, but of course outside of competition, it doesn’t have to be a square
at all, a large circle will do the job just as well.
Why then, does the pilot of the full-size add down trim and speed up in the landing circuit,
surely this is not the thing to do? Actually, it’s a pretty nifty idea, because it gives you
options both sides of your rate of descent in this configuration. If the computer in your
brain beeps and says, ‘too low too low... you can’t get back from there’ you can opt to
leave the spoilers alone and rely on your extra airspeed to bring you home. If the
converse applies (Beep! Beep! Too high), you can pull out the spoilers until things start
looking better. But, I hear those of you still awake say, surely if you are short of the height