Having just finished my 2.6m ASW28.
It has high loading of 27oz/ft2. (Ouch!)
I have just set up crow.
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I then upgraded my tx to a jr3810/8103 to additionally be able to set camber and flaps independantly of crow.
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I understand the advantages of crow for landing, including effectively introducing large washout to help avoiding tip stalling, but please can someone explain when I would use flaps and camber.
e.g., any use of flaps during launch?
How many degrees?
If lift drops, can I add touch of camber?
Do I then need to be careful about tipstalling because we are increasing angle of attack of whole wing including tips?
Or do I set camber to add slight washout by moving flaps slighly more than ailerons?
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(note, reflex will not be set as flaps have nil up movement)
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Above are all the issues spinning round my head.
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Please comment,
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Rgds, Steve

Wow so many questions LOL. First, for a winch launch you will want a touch of camber. The amount depends on the airplane but start consevitive. I also use a mix that adds camber as elevator is applied. When circling in lift I also have a slider set up so I can manually add some camber. In zero lift or sink you want zero camber. You need to be able to travel effieceintly.

I wrote this as part of a set-up for a Hitec Optic 6, but it might be useful to you.  Ignore teh references to the Optic 6 and just understand the use of the mixes.

<font face="Verdana" size="2" color="#191970">GETTING FANCY WITH MIXES

This is where sailplanes get a bit involved. Since we don't have a motor,
and we use a winch or a hi-start to launch the plane, we tend to what to use
the surfaces of the plane to either generate maximum lift or minimum drag at
various parts of the flight. We are trying to suck every bit of energy out
of the air that we can, or to conserve as much of our energy as possible for
thermal hunting and finally for landing. Remember, when a glider comes in
for a landing, it is going to land. There is no going around for another
try! This is skillful flying because there is no motor to save you or pull
you out of a bad situation. This is fun!

I will discuss the mixes I would set up on the Optic 6 if I were going to
fly one of these planes and how and where I would use them. Other pilots
might use different combinations but these are my suggestions. You don't
NEED all of these, but let's explore them.

V-tail if it is a V tail plane- page 35 - we discussed this above. If you
don't have a V-tail, skip this one.

Aileron Differential - page 31 - When we fly gliders we learn that using
both ailerons to roll the plane is good, but that the down aileron can
induce more drag than the up aileron. It can also tend to introduce
something called adverse yaw. So it is common to set the down aileron to a
lesser throw than the up aileron. 50% is typically a good setting for
starters. Some planes don't need this, but most benefit from reduce drag
and better handling. This mix is on all the time and can not normally be
turned off in flight.


Aileron-Rudder- page 36 - Coordinated turns - When you use the ailerons to
bank the plane to redirect the lift, the plane will enter the arc of the
turn. We may use elevator or we may not, depending on the plane. In many
cases the nose will not track true to the circle. This induces extra drag.
By using the rudder, in coordination with the turn, we can bring the nose
around more smoothly getting a better, lower drag turn. Coordinated turns
are also common on power planes but, frankly, since you have all that motor
up there to overcome the drag, many pilots ignore the rudder. Sailplane
pilots love their rudders so much we have the radio add in some rudder
whenever we use the ailerons. I usually start with a 20% rudder setting and
test the plane in the air to see if I want more or less. On most radios you
can turn this mix on and off in the air so you can see if the rudder is
really helping the turns.


Launch/Landing - The Optic 6 has a feature called landing that sets the
flaps and the elevator to a preset that we choose It suggests we use this
for landing purposes but I am going to use crow for that so we can change
the use of this mix to create a launch mix. On launch we want to have the
flaps drooped a bit to create a lot of lift. During the winch or hi-start
launch we can afford the extra drag because the tow line will be pulling the
plane. With the flaps down, say 20%, we can get a much steeper climb on
launch and get much higher launches. So, when we prepare to launch, we flip
the switch and the flaps will go to that preset. Over time we will learn if
we want to add some elevator to this setting, which the Optic allows, to get
the perfect launch.


Crow - page 37 - This is a form of glide path control. We use the flaps,
ailerons and the elevator to change the glide character of the plane. This
is normally used to assist in landing, but can also be used to help us get
out of very strong thermals that might otherwise suck our plane into the sky
and out of view. A reasonable setting would be 80% flaps, 25% ailerons and
about 10% down elevator. This is a very very very plane specific mix so
this will have to be tested carefully in the air as this could be way way
off and make the plane hard to control. Every plane is different. On the
Optic 6, this will be controlled from the left side slider/levers and is
proportional so that we can have full crow, or partial settings so we can
adjust the surfaces according to our desired effect on the plane. I like
the side sliders for landing. I use this to control the flaps on my Futaba
9C, as well as my spoilers for my RES ships.


Camber - page 32 - Camber refers to using the flaps and ailerons in
coordination to change the shape of the trailing edge while we are in
flight. In effect we are changing the shape of the wing, thus changing the
way the plane flies. Common uses are to lower the flaps and the ailerons
slightly to create more of an undercambered wing shape while we are in a
thermal. While this induces more drag, it also gives us more lift. When we
are solidly in a thermal we can afford a little more drag to get that extra
lift so we can draw more energy out of the air and have the plane lift
faster in the thermal.

The other use is to reflex the trailing edge, which means to raise the
ailerons and flaps a little. This can be as little as 1/16 of an inch but on
some planes this will dramatically reduce drag and the plane will pick up
speed rapidly. We lose some lift but this can be very helpful when we are
in a region of falling air, called sink. We want to get out of this area as
fast as possible so we sacrifice a little lift to get though the bad air
quickly.

I believe the camber feature gives us one setting we can control from a
switch. So I will suggest we use it to set a slight reflex setting to get
us through the bad air quickly.


Elevator Flap, also called snap flaps - Page 36 - When we are in a thermal,
we have lots of lift around us. We will be using a little up elevator to
help us climb in the lift. What we can do is set up this mix which will add
a little bit of down flap with we pull up elevator causing more lift from
the wings. As such the plane will climb in a flatter, more efficient manner
rather than angling up the nose to the extent it would normally. This
little bit of extra lift can make a big difference when we are in a thermal.
Normally this setting can be switched on and off in flight as we don't want
this on in normal flight. We will only turn this on when we are in a
thermal. I will suggest about 5% down flaps to start. We will see, over
time, as we tune the plane, if we want more.


Let's walk through a flight:

Launch - Flip that switch for our launch setting and send the plane up the
launch line. At the top of the launch we will turn this off so that we are
in normal cruise mode. We are now 400-600 feet up and looking for lift.
Let's go hunting!

We spot some lift and we start to circle. We flip on Elevator-flap mix,
E-F, so when we pull elevator slightly, we get a tiny bit of flap to help us
climb smoothly in a thermal.

We lose the lift so we turn off E-F and go hunting again. We hit some fast
falling air, sink. We want to run through some sink, so we flip our
camber/reflex preset on, flaps and ailerons move up a little, and the plane
moves quickly through the sink. When we are in more buoyant air we flip
this off.

We catch some lift and circle up again and turn on E-F to rise in the
thermal. We have been in this thermal for 20 minutes or so. We hit about
1000 feet and have ridden the thermal about 1/2 of a mile down wind. Time
to head home and prepare to land. During our return run we will fly in
cruise or we might turn on that camber/reflex preset again to help us
penetrate through the head wind. Remember we have no motor so we are flying
upwind in a glide.

OK, time to land. We set up for an approach into the wind. We want to have
more energy than we need to make it to the landing mark because a gust might
hit us and rob us of energy causing us to fall short. As we finally get
close and are confident of making the landing zone, we can start to use that
Crow mix to lower flaps, raise ailerons and mix in elevator to keep the
plane level or slightly nose down. As we judge our speed we may go full
crow to "put on the breaks" so that when we touch we are moving slowly and
will not overshot our mark.

Cool?</font>