Seems like many people are trying thermal sailplanes for the first time in AFPD. I've been able to ride thermals pretty well in AFPD so I'll share my experiences as just one example.

I like flying "full house" ships (both flaps and ailerons) in the 2m range. The closest option I have in AFPD is the Ventus, a 3m full house scale sailplane. (If you are listening OMP or Ikarus please add some 2m full house planes! I can't find any even in the download sites. And no elec motor please!).

CG
The stock Ventus is very stable and less responsive to thermals than I'd like. It also tends to pull up from its best glideslope instead of staying on slope. I copied the Ventus to another model name and moved the cg back to -1.75 in based on the "dive" test. It still pulls out of a dive on its own but not as bad as it used to. Move the cg back to make the plane more pitch neutral (holds a given pitch) but not so much to jeopardize control. If the plane gets too twitchy or stalls easily, you've moved the cg back too far. Elevator trim also affects this so you need to adjust both at the same time.

I'll save flaperons and landing crow settings for another post.

FLIGHT MODES (Flap settings)
I prefer to have 3 preset positions for the flaps: speed/reflex (slightly up), cruise (neutral), and thermal/loiter (moderate down). The purpose of these settings is to change the wing camber and optimize aircraft performance in each flight task. If you want to cross the field with the minimum loss of altitude, move the flaps to the speed setting. The plane's path will steepen slightly (let it go!) but it will cross the field so quick it won't lose much height. Use the neutral cruise setting to sniff around an area for lift. This setting balances altitude loss with a moderate speed to cover an area. Kick down to thermal flaps to slow down if you think you've found some lift. At the slower speed you can turn tighter to stay in a thermal. The ventus flies so fast you really need the cruise and thermal settings to slow it down to detect thermals and stay in them.

Since we don't have guages you'll have to load your plane into a *non photo scene* so you can get the camera up really close to see the flap deflection when you make your adjustments. Use the up arrow key to move the camera in close, and the left/right keys to move behind the plane. Someday I'll research the wing type and put in ideal settings but for now I set the reflex flaps to about 3 degrees up; really just a smidgen. I set the thermal flaps to about 20 deg down. This seems too much to me now but the Ventus doesn't seem to suffer from too much drag.

WHERE TO FLY
Pick a scenery that has a large open field. I often fly at "rottenburg". It is a large empty field with some light industry in the background and a very large, distant hill with a nice little house on it. I make the house on the hill my "upwind" reference. The hill is too far away to affect thermal patterns or cause turbulence in the flying area. Below I have suggested weather settings. Beginners may want to try turning off wind, but be cautioned that this makes the flying conditions unrealistic. Turn wind back on as soon as you can so you can learn how it will be in the real outdoors. The wind settings I suggest are still a "very good flying day" so the wind shouldn't give you much of a problem.

Wind: 2-3 m/s and set FROM the direction of the house on the hill (130 degrees)
Turbulance: 0.5
Thermals: anywhere from 3 (challenging) to 5 (obvious, but good for beginners)

LAUNCH
Let the plane turn into the wind while sitting on the ground. Retract the airbrake. Retract the wheel. Set flaps to "speed".

Press H once (50m challenge) or twice (100m beginner) to launch the plane. Let the plane fly away for one or two seconds, then save this position with F3. From now on just use F4 to start again. (Make sure to be in "speed" flaps each time you restart).

Fly at "speed" upwind for about 10 seconds to extend away from your pilot position. I find it much easier to hunt thermals if I can watch my plane from the side rather than from directly below.

HUNTING
Once you are in the upwind hunting area, switch to cruise or even thermal flaps. Try to trim the elevator to maintain a steady shallow dive angle. Reduce "porpoising" as much as you can. Once you have a steady glide slope, note that your plane does indeed sink slightly but noticeably. This sounds silly but it is important. In dead air, your plane SINKS. The most subtle clue that you are in or a near a thermal is your plane will MAINTAIN altitude. This is often missed by power pilots who are used to their planes flying level.

So fly back and forth across the wind, staying upwind (in the direction of the house on the hill). Sometimes you may never find lift or you'll dork a turn and lose so much altitude the game is over. F4 and "speed" back into the hunting area. Note that the plane will want to climb whenever you point into the wind. Don't confuse this with a thermal. Just continue through your turn.

UP WE GO!
Hey, did you realize that in the last few seconds you weren't sinking? Or maybe you even climbed a bit? A thermal "bump" can be as subtle as this; your plane stays level or rises slightly without pitching up. More obvious signs include the tail lifting or a wingtip lifting (don't confuse this with turbulence though). Time to switch to thermal flaps, slow down and begin circling in the area. Begin with shallow circles (30 deg bank), don't lose excessive altitude while circling. Keep a shallow steady sink to maintain airspeed. Two or three circles is all you need to detect a thermal. If nothing is found, switch back to cruise (optional) and move to another nearby area to begin hunting again.

You may notice that your plane wants to maintain or climb on half the circle and sink on the other half. Bias your circling to the "rising" side. If you move into position in a thermal you should be able to increase bank angle to 45 degrees or more, yet your plane will still climb!

Now that you are in lift, maintain a steady bank angle. The wind will want to extend your circle downwind. Let it. You want to travel downwind with the rising thermal.

Now its entirely up to you how long you want to stay with this thermal. I generally bail out at 500ft and head upwind again just to keep things challenging. In any case don't fly downwind of the pilot position too much; you may not get back. When you are done with this thermal or lose it, remember to use "speed" flaps to head back upwind to the hunting area again.

If I figure out how I'll try to post an AFPD video soon.

Good luck and happy hunting!
Clark
(FallingWithStyle)