Roban - World Class Scale Helicopters

Official Freewing Twin 80mm F-14D Tomcat Thread

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  • rifleman_btx
    me

    • Dec 2016
    • 5246
    • West Point TX
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    #1341
    I'm guessing I'll need to run the ailerons on a Y on a different channel. I can't get it to turn worth a crap swept.

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    • kallend
      -----

      • Nov 2016
      • 1871
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      #1342
      Originally posted by rifleman_btx
      I'm guessing I'll need to run the ailerons on a Y on a different channel. I can't get it to turn worth a crap swept.
      What is your current channel configuration?

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      • xviper
        Hobby Squawk Regular

        • Jan 2014
        • 8766
        • Calgary, Canada
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        #1343
        Originally posted by rifleman_btx
        I'm guessing I'll need to run the ailerons on a Y on a different channel. I can't get it to turn worth a crap swept.
        Do you have tailerons? In swept mode, this thing needs tailerons on high rates to bank and turn.

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        • rifleman_btx
          me

          • Dec 2016
          • 5246
          • West Point TX
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          #1344
          Yes I have those but I have it setup completely stock and when I try to bank it doesn't do a thing until I'm at almost full bank defection. Then it just whips over uncontrollably. I'm feeling like the ailerons are canceling out the tailerons until the deflection is enough to get beyond the ailerons. Seems weird but that is what it feels like is happening now

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          • xviper
            Hobby Squawk Regular

            • Jan 2014
            • 8766
            • Calgary, Canada
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            #1345
            Originally posted by rifleman_btx
            Yes I have those but I have it setup completely stock and when I try to bank it doesn't do a thing until I'm at almost full bank defection. Then it just whips over uncontrollably. I'm feeling like the ailerons are canceling out the tailerons until the deflection is enough to get beyond the ailerons. Seems weird but that is what it feels like is happening now
            Each of the ailerons on mine only go UP, not down (unless they are being used as flaps) and they go up very little, maybe a few mm max. This is the same when the wings are swept, even though I haven't flown mine swept yet. You may be right about the ailerons blanking out the tailerons. With either open or swept wings, my tailerons do most of the work for banking.

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            • rifleman_btx
              me

              • Dec 2016
              • 5246
              • West Point TX
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              #1346
              Yeah thats what I was thinking as well, I would shut them down on sweep, that's my plan anyway, I'll let you know how it works out for me when I get it back out next week.

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              • kallend
                -----

                • Nov 2016
                • 1871
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                #1347
                The forecast finally was OK yesterday so I took it out to maiden it but by the time I got to the field the vis. had dropped to 1/2 mile and the ceiling to 600ft and it was starting to drizzle, so I just flew my trusty old (Dynam) Meteor instead and came home.

                Questions for those who have disabled the ailerons when the wings are swept - what did you do with the aileron rates? Also is it worth implementing full span flaps?

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                • pullupnow
                  Pilot

                  • Feb 2018
                  • 70
                  • Long Island NY
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                  #1348
                  Originally posted by kallend
                  The forecast finally was OK yesterday so I took it out to maiden it but by the time I got to the field the vis. had dropped to 1/2 mile and the ceiling to 600ft and it was starting to drizzle, so I just flew my trusty old (Dynam) Meteor instead and came home.

                  Questions for those who have disabled the ailerons when the wings are swept - what did you do with the aileron rates? Also is it worth implementing full span flaps?
                  Most of the guys flying the tomcat are locking out the ailerons during swept wing flight. About 60% rate on roll and 100% pitch for swept. On mine that gives a pretty decent roll rate and not too sensitive. Make sure you leave full pitch travel as it tucks the nose in a steep turn with the wings swept. As far as the full span flaps, They look cool but you lose quite a bit of roll authority on the approach and there is quite a lot of nose down pitch moment with the ailerons drooped as flaps. I personally had some pretty heinous landings in that configuration. Its much more predictable and docile with the factory flap configuration. Probably the best upgrade I did was replacing the stab servos with hitec d 85's and 440 hardware. Much more positive feel. It's fine in the meantime stock.
                  You will love this plane! It's like your own personal airshow.

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                  • pullupnow
                    Pilot

                    • Feb 2018
                    • 70
                    • Long Island NY
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                    #1349


                    have fun
                     

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                    • kallend
                      -----

                      • Nov 2016
                      • 1871
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                      #1350
                      Originally posted by pullupnow

                      Most of the guys flying the tomcat are locking out the ailerons during swept wing flight. About 60% rate on roll and 100% pitch for swept. On mine that gives a pretty decent roll rate and not too sensitive. Make sure you leave full pitch travel as it tucks the nose in a steep turn with the wings swept. As far as the full span flaps, They look cool but you lose quite a bit of roll authority on the approach and there is quite a lot of nose down pitch moment with the ailerons drooped as flaps. I personally had some pretty heinous landings in that configuration. Its much more predictable and docile with the factory flap configuration. Probably the best upgrade I did was replacing the stab servos with hitec d 85's and 440 hardware. Much more positive feel. It's fine in the meantime stock.
                      You will love this plane! It's like your own personal airshow.
                      Thanks. Good to know.

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                      • Evan D
                        I'll fly anything

                        • Jan 2016
                        • 5392
                        • Charlotte
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                        #1351
                        Agree with disabling ailerons when swept and I kept normal flaps. I tried full span and liked the feel of the normal ones better.

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                        • kallend
                          -----

                          • Nov 2016
                          • 1871
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                          #1352
                          Looks like my maiden is going to have to wait for spring. 6" of snow today, and freezing temperatures all next week, then off to Costa Rica for 5 weeks.

                          At least the long delay has given me plenty of time to program the radio (iX20 + AR10360T) and make ordnance and "afterburners".

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                          • Gvasiloff
                            Member

                            • Aug 2019
                            • 42
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                            #1353
                            Originally posted by kallend
                            The forecast finally was OK yesterday so I took it out to maiden it but by the time I got to the field the vis. had dropped to 1/2 mile and the ceiling to 600ft and it was starting to drizzle, so I just flew my trusty old (Dynam) Meteor instead and came home.

                            Questions for those who have disabled the ailerons when the wings are swept - what did you do with the aileron rates? Also is it worth implementing full span flaps?
                            Full-span flaps definitely slow this jet down even more and look more scale, but it is a double edged sword. It does make the jet more prone to tip-stalling if you let the angle of attack creep up or try to flare too much, especially with a crosswind. I've found that making the aircraft roll with tailerons only and about 15% rudder mix with full span flaps down controls it nicely in the landing configuration and reduces the tendency of tip stall. She also needs a lot more power in the turns due to the extra drag and a lot of extra up elevator mix with the full span flaps, so keep that in mind. I have an "emergency" normal flap mix on a separate switch that I can use to go back to normal inboard flaps only if the crosswinds pick up while flying. She is much more forgiving in that configuration, but she comes in a lot hotter. Watch how Rich Baker (RCInfromer) and the RC Geek land this jet in their youtube videos. It's not a nose-high approach, but rather a flatter almost nose-down attitude with power off. Almost like landing a trainer. Feeding in a little power at the flare to help cushion the landing is a good thing and also helps reduce the tip stall tendency.

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                            • SanExup
                              Member

                              • May 2020
                              • 912
                              • Western Wy.
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                              #1354
                              Gvasiloff Is your rudder mix the same direction as your flaperon input or opposite?

                              I reread your post and I guess you're using fullspan flaps as just flaps and tailerons for bank? So is your rudder mix yawning in the same direction as the tailerons or opposing?

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                              • xviper
                                Hobby Squawk Regular

                                • Jan 2014
                                • 8766
                                • Calgary, Canada
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                                #1355
                                Unlike many of my planes that "balloon" when flaps are deployed, this F-14 nose dives like a whale going deep. It has some of the most severe UP elevator compensation that I've seen on any of my planes. I also use full span flaps and on "full" flap deployment, the nose dive is very pronounced. Elevator compensation is quite astonishing and I was worried I might run out of elevator for pitch control when landing, but there is plenty left for the job. I don't hit full flaps till I'm on final. I keep some throttle as it descends and my last few landings were very greasy. I've also noticed that rudder input seems to augment the roll. Right rudder, right roll. I try not to use too much rudder when near the ground at landing. This can can cause a severe roll and cause a wingtip to drop suddenly. I lower gear and go 1/2 flaps on the downwind, then turn for final. Best is to get it lined up with the runway long before getting close to the threshold, hit full flaps on the straight and true, keep adequate throttle all the way to about 5 feet off the deck. If it goes crooked, lift flaps, go around and try again. Using rudder to straighten out is still too dangerous for me.
                                PS. I may have mentioned this before. My ailerons only go UP on the side that's needed and only a few mm (less than 5mm), even when fullspan flaps are deployed.

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                                • rifleman_btx
                                  me

                                  • Dec 2016
                                  • 5246
                                  • West Point TX
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                                  #1356
                                  My seems to float when I use my flaps, I'm not sure what I have different but it really doesn't seem to sink. As per my video I posted.

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                                  • xviper
                                    Hobby Squawk Regular

                                    • Jan 2014
                                    • 8766
                                    • Calgary, Canada
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                                    #1357
                                    My initial expectation was for it to "float" when flaps came down. I was quite surprised when it took a dive. Both my batteries are as far back as they can go and I believe the plane is balanced as per the book.
                                    I just checked my TX. On full flaps, I've got 20% elevator UP compensation. In contrast, my OV-10 has 18% DOWN elevator comp.

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                                    • Gvasiloff
                                      Member

                                      • Aug 2019
                                      • 42
                                      • Send PM

                                      #1358
                                      Originally posted by SanExup
                                      Gvasiloff Is your rudder mix the same direction as your flaperon input or opposite?

                                      I reread your post and I guess you're using fullspan flaps as just flaps and tailerons for bank? So is your rudder mix yawning in the same direction as the tailerons or opposing?
                                      Yes, the rudder is in the same direction as the turn. It helps the nose track around the turn and keeps the banking more coordinated with the flaps down. Another tip is to make them deploy over 3-4 seconds vice instantly. That gives your elevator mix time to cancel it out. If you do it with the aircraft nice and slow, the transition should be seamless and the nose shouldn't dive like others have stated bellow. It may take a few flights to get the amount of elevator trim just right. The way I do it, is I make my flap positions different flight modes and manually trim the elevator in flight to where I want it with the different flap settings. After I land, I go to the servo page of the transmitter and right down the position of the elevator servos at each flight mode and then zero them out. Then, I dial in elevator to flap mixes for each flap position until the servo position matches what i had written down from the trim positions of each flight mode.

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                                      • rifleman_btx
                                        me

                                        • Dec 2016
                                        • 5246
                                        • West Point TX
                                        • Send PM

                                        #1359
                                        Originally posted by xviper
                                        My initial expectation was for it to "float" when flaps came down. I was quite surprised when it took a dive. Both my batteries are as far back as they can go and I believe the plane is balanced as per the book.
                                        I just checked my TX. On full flaps, I've got 20% elevator UP compensation. In contrast, my OV-10 has 18% DOWN elevator comp.
                                        Indeed, I can say that I do things when I fly I'm not even aware I am doing for correction when I fly. So I may be totally off base with my assumption of floating as I may be subconsciously adding up elevator without even thinking I'm moving anything. I don't know, but I'll find out tomorrow when I take her out again.

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                                        • SanExup
                                          Member

                                          • May 2020
                                          • 912
                                          • Western Wy.
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                                          #1360
                                          I guess I have assumed that holding rudder with bank will create a skidded turn and potentially stall the inside wing. And wouldn't full span flaps exacerbate that by creating more drag? I'm wondering what effect tailerons only has on creating or relieving adverse yaw? I thought with coordinated turns that you use rudder to initiate the turn but are looking to neutralize it once in the turn. I'm not claiming to know but simply trying to understand. I have yet to use full span flaps on any of my planes yet. Or mix in rudder control for coordinated turns. Again, I'm just trying to understand, to avoid the turn, stall, spin maneuver.

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