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Target Model
This setup procedure is intended for a scale model glider that has spoilers, a retractable gear, and a tow release in addition to the typical 6 channel full house controls (ailerons, flaps, rudder/elevator or vtail).Limitations
Although it would be best to use a 9 or more channel transmitter to control a scale model glider, it is possible to do a reasonable job with an 8 channel transmitter. The main limitations with the setup presented here are: the amount of flap throw (max throw is 140% of aileron throw), retractable gear will "share" a channel with the tow release, and crow mode (ailerons up when flaps down) will not be programmed (spoilers can be used instead). The reason for the flap throw restriction is to allow entire trailing edge mixes (camber, elevator->flap), with equal flap and aileron movements.
At the sacrfice of some aileron precision and servo leverage, aileron mechanical throw can be increased, and aileron differential values decreased to allow more flap throw with the setup described here. For example, to get flap throw range to +12.5 degrees, -87.5 degrees, you would set aileron mechanical throw to +/- 35 degrees. Aileron throw could then be reduced to +25 degrees, -12.5 degrees using 70%/35% differential values.
Caution
Note, during the setup process, sticks and knob will have too high of a response. Be careful to not exceed servo or mechanical limits when moving the sticks or knob. Once the setup is completed, this will not be an issue.
Model channel settings:
channel 1 - AIL1 right aileron
channel 2 - ELE elevator
channel 3 - ABK spoilers
channel 4 - RUD rudder
channel 5 - FLP2 right flap
channel 6 - FLP1 left flap
channel 7 - AIL2 left aileron
channel 8 - CH8 retract / tow release
If vtail:
channel 2 - ELE1 RUD2 - right ruddervator
channel 4 - ELE2 RUD1 - left ruddervator
Transmitter special controls:
Throttle stick): (ABK - air brake).
SWA up - camber
SWA down - flaps
Switch B: spoilers
Switch F: retract / release
Launch mode: Three position switch.
Switch E (left) on 8UH, switch G (right) on 8UA.
start/normal/speed modes.
All Knobs: only used during setup.
Initial transmitter setup
Set transmitter model type to GLD2FLP, enable aileron differential (if it isn't already) 100% up/100% down for now. If you had a v-tail enable it now also, setting all values to +/- 50%. Wiggle sticks, and turn flap knob small amounts (it's sensitive); and reverse any channel for any throw that is backwards. Note, the flap knob is turned clockwise to lower flaps.
Mechanical setup
Note, for trailing edge usage, ATV's will be adjusted to make the flap and aileron responses even, and then the mixes (like aileron differential) will be used to get normal response to control inputs. The mixes are limited to 100%, but ATV values can go up to 140%. This setup has a limitation: total mechanical flap throw cannot exceed total mechanical aileron throw (before differential is applied) by more than 40%. Use kit recommended values, except if the flap thows exceed the ratios listed below. If you don't have recommended values, use the throws listed below for setup.
Mechanically center and adjust linkages so that throws exceed recommended values, preferably just slightly, with ATV values at 100%. Don't adjust the ATV values yet; leave them at 100%. The ATV values will be "tweaked" later on in order to get equal trailing edge movements, and later still, other mixes will be used to set the actual throws. For now all that's needed is to set the throws so that they exceed (just a bit if possible) the desired throws.Avoid exceeding mechanical limitations with too much stick or knob movement. Excessive mechanical throw can be compensated for, but there will be some loss of precision and servo leverage (strength).
The term chord is used here to mean the distance from front to back of the control surface being setup (aileron, flap, etc).
Ailerons: thermal models up/down 25% chord (15 degrees) to
up/down 34% chord (20 degrees)
sport models up/down 40% chord (25 degrees)
For now, leave the ailerons with equal up/down throws. If the ailerons mechanically can't go down as far as up, then adjust aileron differential "down" percentages to 50%, so that you can move the stick enough to set the up throws without bottoming out the opposing aileron. After throws are verified adjust all aileron differential values back to +/- 100%.
Flaps: up = 0.5 times the aileron up throw
down = 2.3 times the aileron up throw
To get this much differential in the flap throw, set the servo control horns so they're angled towards the flaps (assuming servos mounted under wing). Use the flap (CH6, left) knob (carefully) to check flap throw.
Elevator: +/- 25% chord (15 degrees)
Rudder: +/- 25% chord to +/-50% chord (hard to have too much rudder).
With vtail, +/- 25% chord (same as elevator).
Set ATV values for tail surfaces.
Adjust the ATV values for elevator and rudder to get desired throws. Use the values from above as a guide if you don't have recommended values available.
Set ATV values for ailerons and flaps.
Aileron and flap ATV values will be set (tweaked) to equalize trailing edge control (flap knob, elevator->flap, camber) throw response of flaps and ailerons. The other mixes will then be used to set the actual desired throws for ailerons and flaps. The reason for this is that the Futaba's FLP->AIL mix (trailing edge mix) doesn't allow values greater than 100%. Normally this would result in less aileron than flap response to trailing edge controls. So the idea here is to use the ATV values to get these throws even for trailing edge controls, and use the other mixes later on to set actual desired throws. Don't worry, there's enough "programmability" left in the other mixes to compensate for these "tweaked" ATV values to set desired aileron and flap throws, even if you need to adjust the aileron ATV values 1.4 times as much as the flap values to get them equal.
Enable FLP->AIL mix, set left value to +100%, select right value, and with the flap (CH6) knob set so the flaps are centered, press both + and - keys to set flap knob offset for this mix. Carefully twist the flap knob small amounts, so that the flaps move up and down half the desired aileron up throw distance. The ailerons will probably move less than the flaps. If this is the case, increase ATV values for the ailerons up to 140%. If this isn't enough, you'll need to reduce the flap ATV values, which will reduce total flap throw somewhat. Adjust the ATV values until entire trailing edge, both flaps and ailerons, all move equally in response to twisting the flap knob enough to move all of them up and down half the desired aileron up throw distance. Again, avoid twisting the flap knob too much.
Set aileron differential
Adjust both up and down values for each aileron to get desired throw response from the ailerons. Typical up/down differntial ratios range from 2:1 to 4:1.
Set butterfly flap mix(es)
Caution, on some models, flaps can sometimes droop below the fuselage. Skegs can be mounted on bottom of fuselage to prevent this. If this is the first model you fly where the flaps can snag during landings, you may consider reducing the amount of droop on butterfly mode to prevent this until you get use to retracting flaps a bit during landing.
Flip Switch A down, and set offset to near top of throttle stick throw (suggest 85%). Adjust flap throw value, usually a large negative percentage, to get desired droop. Do not adjust the ATV values. It may be that you can only get 40 to 45 degrees of down flap with this setup. This is OK, since the model also has spoilers to slow it down.
At this point all the standard control throws should be set. The tweaked aileron and flap values have been compensated for with the mixing procedure above.
Switch F retract gear / release toggle
Turn CH8 knob to the stop so gear and release are deployed.
Pmix2: CH8->CH8 -100% -100%,
press +/- keys to set offset (+/-100%), SWF down.
Turn CH8 knob to the other stop and leave it there.
Toggle switch F to make sure gear/release are working.
Switch B spoilers toggle
Pmix6: ABK->ABK pos1 -100% pos2 -50% pos3 0% pos4 +50% pos5 +100%
This "disables" throttle stick from affecting channel 3.
Turn CH7 knob all the way clockwise.
Pmix3: CH7->ABK -100% -100%,
press +/- keys to set offset (+/-100%), SWB down.
Turn CH7 knob to the other stop and leave it there.
Toggle switch B to make sure spoilers are working.
Set butterfly elevator mix
bfly: try initial value of -10%, adjust during initial flights.
Set up Camber mix:
pmix4: ABK->FLP 0% -10% link on trim off ofst 85% SWA up
Adjust % so that trailing edge droops about 5 degrees (9% chord).
pmix5: ABK->ELE 0% +5% link on trim off ofst 85% SWA up
Adjust elevator trim during initial flights for level glide.
Pmix5 only needs link on for vtails.
(note entire trailing edge will move).
Set up ELE->FLP mix:
try an initial values of -15% / -15% readjust on initial flights.
(note entire trailing edge will move).
Set up Pmix1: AIL->RUD mix:
Pilot preference here, some prefer none, others 50%.
Readjust during initial flights.
Set up AIL->FLP mix:
+50% +50% (pilot preference, improves roll response).
Start
Droop flaps a bit more than ailerons, possibly raise elevator a tad.
Be conservative on first few launches while adjusting this.
Speed (reflex)
Raise flaps and ailerons a bit (1/16 inch or so).
Adjust elevator during initial flights.
Reduce flap knob sensitivity
Enable FLPTRM and reduce percentage to minimal value that still allows
the flaps to be centered. Go to FLP->AIL mix, and set the offset again.
That's it, ready for first flight. When trimming, avoid modifying ATV values (only if throws get unequal). Use the mix values instead. Typically you'll be adjusting aileron differential, rudder mixing, elevator setting for various modes, start and speed modes during the initial flights.