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How to turn
Every
turn should be a descending turn.
Many
mistakes are made by not giving enough banks when entering turn.
Because of this, the glider will come out of the turn nose up attitude,
so more aileron and elevator input are needed to correct it.
All of these unnecessary moves make glider fly dirty and slowly.
Bank angle should be a little past vertical (100 to 110 degree). If you
role more, it will make a split S turn and lose too much height.
When you have proper amount of banking it will come out of turn with about
70 degree banks. This makes less use of aileron movement until the next
turn.
The image is as if you are gliding along the line of coil spring continuously
downwards spiral turn.
When you make knife edge turns it will come out verticaly and you need
to level it and bank all the way back to 100 degree again for the next
turn.
This big movement makes it decelerate.
You need to move the aileron stick smoothly and be sure to move it back
to neutral before pulling the elevator. Otherwise the compound input works
like a crow brake and cause rapid deceleration.
This is very important skill. You need to practice this movement until
you cen do so without thinking.
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You can watch World Champion Wolf Fickensher's 2002 WC flight. This is
very good example to see how top flyers fly.
watch it full screen at HQ. Practice with your transmitter in your hand
and imitate as you are actually flying this glider.
http://www.youtube.com/watch?v=tPVEA3EX1Ow
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It is a mistake thought as for the turn, there seem to be a lot of people
who think that it should do the anticepate turn. All the top fliers in
the world turns after hearing the sounds of the buzzer. They flies surely
because cutting turn will ruin the round.
but then how could they turn so precisely?
Four elements necessary for quick turn.
1. CG location
Set the CG further back in order to make it unstable so it can follow rapid attitude changes. There is a big difference in the sharpness of the turn when you compare gliders with their CG at 40 to 42% to the one with CG at 35%. Move the CG as far back as possible.
2. Elv to Camb mixing (snap flap)
To make a small turn, a big lift is necessary. You shouldn’t rely on the angle of attack change by the elevator alone. Mixing more camber with elevator to create more lift only for that time is very effective.
Try mixing 3 to 5mm down camber for the full up elevator to start with and find out the best mixing amount for your style of flying.
When you hear the sound “Zaah” at the turn, it is the sound of flow separation over the wing surface. When this happens, rapid deceleration occurs. Decrease the amount of mixing and try to fly a little wider turn. This prevents flow separation and keeps a higher speed.
３．Make ready position early
In the power of the latest F5B machine. It only takes 2~3seconds in each lap. The turn buzzer rings before you realize. Starting to level wing after the turn you realize you must bank again for the next turn.
The time between them is about 1 to 2 seconds. Once you get late in that sequence you will be over compensating every move and good record cannot be hoped for.
Instead of thinking what to do at each position in the air try smooth flying with rhythm. Most important tip is to recognize half way point while flying and get ready for next turn.
４．Elevator setting and the technique of pulling and releasing of the elevator stick
Giving a sudden full up elevator simultaneously with the sound of the buzzer
might cause detachment of the air flow over the wing. It is better to mix
elevator with EXP for smooth and gradual angle change. This will also
contribute quick release of the elevator at the exit of the turn.
The technique of pulling elevator is not to pull in a single movement but
do so in two movements. When your helper calls "Ready," touch
elevator a little to make the course slightly curve to the base then wait
for the buzzer to sound. At the sound of the buzzer, pull all the way and
turn hard about 90 degrees and release half then gradually release remaining
elevator to complete the remaining 30 to 40 degree turn. Fig1
In this way, you can shorten the time pulling full elevator which causes a large drag and decelerates the glider.
It also shortens the distance passed over the base line.
When this turn goes well, the nose turns the other way at same time the buzzer sounds.
Explaining this technique in writing takes a long time but this sequence happens within a second in reality. There is no time to think about following each step, so you must practice until you achieve a rhythm.
When you pull full elevator in a single motion: It has to make a 180 degree full turn, but this creates a large drag and it is still facing the other way. This causes it to fly a longer distance.Fig2
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Fig
1
Fig
2
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Should I return the bank to level after the turn?
When you make a knife edge turn it will come out of turn vertically. Then
you must move aileron to level the wing but by the time you level it you
must bank it again for the next turn. This makes a big aileron movement
twice. Inorder to make smaller ailron movement you must bank more than
90 degree (100～１１０）then it will come out of turn in 60～70 degree so you
will have less movement to level or bank.
Many people think better not to touch anything in the first lap. Stay in
knife edge position all the way to the other side and turn it with only
elevator movement. They think it is quicker because you are not deflecting
any wing part, resulting in a very clean flight. But if you keep your wing
vertical your glider has no wing. If you have 60 degree bank your glider
have only half span wing. This gives very bad glide ratio it will reach
other side loseing more hight than leveled wing. You may not have enough
time to level wing in the first leg but must role it back to about 45 degree
other wise you lose too much hight.
As the laps continue, the speed gets slower. Its lift gets too small to
keeps it in projectile with a high bank angle. In total balance it is necessary
to return to level even if you must move it twice both ways.
There are many conditions which make gliders fly slowly but when it is going slowly, it is better to return to level after each turn.
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The example above is in the case of flying from A to B mostly straight.
But there is another way of flying in an oval spiral pattern.
There is no straight line in this pattern. It keeps a 45 to 60 degree bank all the time except when turning at both ends which needs banking of 100 to 110 degree.
You should imagine a big coil spring in the sky and trace it with the same bank.
This method is also very effective because there is almost no aileron movement but you need to pull small amount of elevator continuously.
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