Official Freewing 70mm F-35 V3 (2019 Version) Thread

[rsunleaded]

Well the maiden was an absolute disaster strip had been mowed on Friday and Saturday morningthe breeze was at 15klm/hr straight down the strip couldn't get any better.
so powered up and down the strip it went got a little hop ( have to put in a bit of Expo on the rudder) took off and I was in a mile of hurt, struggling to maintain control flicked to low rates ele and ail still not much better decided to go around and land but didn't make it,
set up was CG 4mm in front of the plastic plate, control throws etc as per manual but I have three positions switch so set up a third low rate as well in case but that didn't help.
Model is repairable and is almost ready to try again, I will order a new fuse and some of the wheel well covers as nose one was completely destroyed but will wait till I can get it sorted before fitting new parts

[xviper]

Well the maiden was an absolute disaster strip had been mowed on Friday and Saturday morningthe breeze was at 15klm/hr straight down the strip couldn't get any better.
so powered up and down the strip it went got a little hop ( have to put in a bit of Expo on the rudder) took off and I was in a mile of hurt, struggling to maintain control flicked to low rates ele and ail still not much better decided to go around and land but didn't make it,
set up was CG 4mm in front of the plastic plate, control throws etc as per manual but I have three positions switch so set up a third low rate as well in case but that didn't help.
Model is repairable and is almost ready to try again, I will order a new fuse and some of the wheel well covers as nose one was completely destroyed but will wait till I can get it sorted before fitting new parts

That's a bummer, man. I know exactly how yours acted. Mine was extremely sensitive to control inputs on the maiden. It would have ended up looking like yours but I remembered a post that says the rates had to be dialed down a lot. My low rate was 35% with lots of expo. I started the maiden on mid rates (45% - 50%) and with the gyro on lowish gain, the flight was manageable. It was still a bit of a roller coaster ride and it rolled like a drill bit. Second flight was on low rates and it was almost like flying a "normal" jet. That was on a GeoTex runway.
The next day was on grass and I believe it was the low rate on the elevator that hampered the plane's ability to rotate and get airborne, so I increased the ELE rate to 80% - still wasn't enough. No more grass attempts with this one. Next time out, will be back to the smooth runway and I'll be changing the control rod to different holes to get back the lower throws but with better resolution and control (ie, rod to a lower hole on the servo arm end and rod to a higher hole on the control surface end.) I think it would have flown much better with rates down to as low as 25% but the resolution would be bad if the rod wasn't relocated. Should also keep a higher mid to high rate just in case. Gyro for sure till I get more used to it.

[rsunleaded]

OK the repairs are done lucky there was no damage to the flight surfaces and fixings for the next time I will set the CG a little bit more forward and of course reduce the travel throws but high rates on the elv will be there so I can get it off out grass strip I will also up the Expo it doesn't look too bad but certainly not pristine

[DaFlyingSnek]

That's a bummer, man. I know exactly how yours acted. Mine was extremely sensitive to control inputs on the maiden. It would have ended up looking like yours but I remembered a post that says the rates had to be dialed down a lot. My low rate was 35% with lots of expo. I started the maiden on mid rates (45% - 50%) and with the gyro on lowish gain, the flight was manageable. It was still a bit of a roller coaster ride and it rolled like a drill bit. Second flight was on low rates and it was almost like flying a "normal" jet. That was on a GeoTex runway.
The next day was on grass and I believe it was the low rate on the elevator that hampered the plane's ability to rotate and get airborne, so I increased the ELE rate to 80% - still wasn't enough. No more grass attempts with this one. Next time out, will be back to the smooth runway and I'll be changing the control rod to different holes to get back the lower throws but with better resolution and control (ie, rod to a lower hole on the servo arm end and rod to a higher hole on the control surface end.) I think it would have flown much better with rates down to as low as 25% but the resolution would be bad if the rod wasn't relocated. Should also keep a higher mid to high rate just in case. Gyro for sure till I get more used to it.

So I keep seeing everyone talk about D/R in percents. What is that in reference to? The total movement of the servo such as it coming straight out of the box, or to the 100% rates the manual states? Such as with ailerons, stock it is up/down around 20 mm but the manual says to have 100% be 15 (or 13, I dont remember) mm.

[xviper]

So I keep seeing everyone talk about D/R in percents. What is that in reference to? The total movement of the servo such as it coming straight out of the box, or to the 100% rates the manual states? Such as with ailerons, stock it is up/down around 20 mm but the manual says to have 100% be 15 (or 13, I dont remember) mm.

As I understand it, what I see in the manual is in terms of control throw measured in mm from neutral. What the TX D/R page tells you is measured in %. If you start at 100%, that’s the maximum throw for that control surface. It may or may not give you the stated throw in mm. Usually, it doesn’t. You can play with various parameters like servo travel in the servo menu, adjust the % rate in the D/R and expo page or change the rod placement on the servo arm and/or control arm holes. For example, I had to dial down the rate to 35% in order to get the stated low rate. I don’t like going that low on the % as this may not give good resolution for the servo movement. That’s why I’m going to change the rod placement to a different hole. This will allow me to get the same deflection of the control surface at a higher % rate, allowing the servo arm to move through a greater arc while maintaining a similar amount of defection in the control surface.

[rsunleaded]

Pics

[rsunleaded]

[rsunleaded]

Oops posted twice

[Lcacing]

So I keep seeing everyone talk about D/R in percents. What is that in reference to? The total movement of the servo such as it coming straight out of the box, or to the 100% rates the manual states? Such as with ailerons, stock it is up/down around 20 mm but the manual says to have 100% be 15 (or 13, I dont remember) mm.

When rates are described by % is misleading because mechanical set up and differences in transmitters translate to different travel. Travel movement by measurements (mm) it’s the same across all variables. Maybe this misunderstanding has caused some crashes, for maiden flight, I found 12mm on high rate for aileron to be plenty, Low rates 10mm.
Elevator travel was initially set by the book.
I do use 25% expo and even that can be confusing. Futaba is a negative number but spectrum is a positive number to achieve same feeling

[DaFlyingSnek]

So currently I have my rates set to Ailerons: 14, 12 and 10mm, Expo: 40% . Elevators: 15 then 13mm, Expo: 37%. Rudders: 22mm, Expo: 45%. People who've flown the plane, does that look ok?

[Lcacing]

So currently I have my rates set to Ailerons: 14, 12 and 10mm, Expo: 40% . Elevators: 15 then 13mm, Expo: 37%. Rudders: 22mm, Expo: 45%. People who've flown the plane, does that look ok?

My CG is at about 8mm aft of the forward edge of the plastic plate. Ailerons are set to 12mm, elevators around 20mm measured at the trailing edge.
Rudders are very effective so I’m down to about 12mm. 25% expo all around.
More importantly make sure you are happy with the CG. I would say start at the fwd edge of the plastic plate the work your way back.
Good luck on your next maiden!!!

[DaFlyingSnek]

My CG is at about 8mm aft of the forward edge of the plastic plate. Ailerons are set to 12mm, elevators around 20mm measured at the trailing edge.
Rudders are very effective so I’m down to about 12mm. 25% expo all around.
More importantly make sure you are happy with the CG. I would say start at the fwd edge of the plastic plate the work your way back.
Good luck on your next maiden!!!

THanks a bunch! I'll be upping the elevator throw to 18mm and 15mm (to be safe) and ill lower the rudder rates as well. Thanks again, happy flying!

[RichJ53]

THanks a bunch! I'll be upping the elevator throw to 18mm and 15mm (to be safe) and ill lower the rudder rates as well. Thanks again, happy flying!

everyone is going to have flight preferences. I found the elevator needs to be at 100% of the available throw. You can always use a lower rate if you find it to much flip your rate switch. . At least you will have plenty of control in the beginning.

Rich

[DaFlyingSnek]

everyone is going to have flight preferences. I found the elevator needs to be at 100% of the available throw. You can always use a lower rate if you find it to much flip your rate switch. . At least you will have plenty of control in the beginning.

Rich

I saw GBlynden's video and he had D/R set to 100% as well. I think for the maiden ill have it to maybe 95% at most.

[RichJ53]

I saw GBlynden's video and he had D/R set to 100% as well. I think for the maiden ill have it to maybe 95% at most.

You should be okay with that.

On my Maiden flight, I took off with low rates (manual settings) from a paved runway. I realized right after take off, the elevator needed more throw. I flipped my rate switch to 100% and never looked back. Also, I have 25% expo for both the ailerons and elevators.
All the best for your first flight

Rich

[EDF_Lover]

I’ve been reading a lot about how to dial in the V3 F35 and have a couple observations after a few dial/fly cycles.

First, the model is heavy so it needs a lot of rolling speed to get in the air. This is relevant because our field is grass and there is a limit to how fast a plane can roll on it. And, I’ve had several takeoff rolls that I had to abort. I’ll note that one time I hit a bump with the nose gear and the nose popped up and the plane was off the ground and climbing at a 30 degree angle a second later. This made me want to know more about the CG and elevator.

Second, this forum makes it clear that the manual is wrong on the CG. 4mm back from the edge they mention is WRONG. The pictures showing the leading edge of the plastic wing fitting are CORRECT. Thank you Hobby Squawk members! Note that the difference between the manual’s position and the correct position. Is probably 20-30 mm. So, it’s a testament to the wide flight envelop of this jet that it ever got off the ground.

Third, ability to get off the ground and “flys well” are not the same. I had to hold a lot of back elevator the entire 90 seconds it took to get it back on the ground. This means it’s not a trim problem. I moved the battery back to the new CG position and reduced elevator throws to 60% because once in the air, 100% is too much. I think people who say 100% is right probably should differentiate between takeoff and flying.

Fourth, :-) 60% wouldn’t get me off the ground. I couldn’t rotate the nose up during grass takeoffs. 75% did the trick. But 75% seems like too much for flying. So I settled on 75% for takeoff and 60% for cruising and landing.

Fifth,I know some guys can roll like crazy and not lose it. Not me. 60% aileron travel is where I started and, with the forward CG issue requiring back elevator, the roll was almost too much to handle at the same time. Long story short, I set roll for 30% for takeoff and landing and 40% for cruising. It rolls plenty fast at 40%.

Sixth, in my opinion, new owners of this jet should start at these kinds of settings until they learn how to take off, fly the pattern, and land confidently. Otherwise it’s amazing ability to pick up speed (!!!!) will amplify every control issue you have with your set up.

Finally, I’m lucky to have a couple members at the field who really know “trim” - mostly Boeing employees- and they watched me fly this pretty closely on the last flight, including the aborted takeoff roll. The consensus was that the nose gear should be a little longer. So my next mod will be the nose gear pin position suggested in other posts. I also plan to trying moving my admiral 60C 4000 batteries back another .5 inch. No more.

Editorial comment: I think there is confusion in this discussion over “travel” “rate” and “expo”. Travel is how far the control surface moves when the servo arm moves from one side of full deflection to the other side of full deflection, noting that servo setup menus allow for this full deflection to be adjusted up a little and down a lot. Then, “rates” are the percentage of full travel that full movement of the stick will produce. And, expo is the “linearity” of how stick movements translate to travel. High expo means initial stick movements from center will yield less movement than when the stick is near its limits. High expo tends to make the center less twitchy but full deflection (to the limit of the rate percentage) will still occur when the stick is fully to the limits. So high expo can seem like you are during sensitivity, but many people over correct when they don’t see a reaction to slight stick movements and slam the stick - producing the full deflection unexpectedly. I can’t tell what people mean when they talk about their expo settings as the key adjustment. I suspect they either mean, or should be focused, on rates.

[Aussie1]

Waiting for our terrible winter weather to clear so that I can maiden my F35. Came in just under 3kgs with full fuel, enough for a 6-7 minute flight. I have reduced the power of the X45 from 11lbs to 7lbs, so will see how it goes.

[EDF_Lover]

Wow. I never thought a turbine mod. Have you flown the airframe with the electric fan? If I had to guess, you are going to get about 200 kph with that thrust. And, the ailerons are so large and effective, roll rates are going to be crazy high. So my advice, not that you are asking, would be to have high elevator rates for takeoff (80%?) but keep the aileron rates in the 40% range. Be prepared for a decent roll, but extreme nose high climb the second it lifts off.

I also learned a lot about its high alpha characteristics by spending by spending time at about 25 meters of altitude trying to simply fly as slow as I could. That’s very important for landing. It rolls more than it stalls, of course until it stalls! Ie it remains controllable longer than you think it will, but when it does break, it’s heavy and takes a lot of altitude to recover.

[RichJ53]

Waiting for our terrible winter weather to clear so that I can maiden my F35. Came in just under 3kgs with full fuel, enough for a 6-7 minute flight. I have reduced the power of the X45 from 11lbs to 7lbs, so will see how it goes.

Wow that's awesome! I hope you put some better servos on the elevators....Maybe you can show us some more build photos plus some videos showing this running.

Thanks for sharing
Rich

[RichJ53]

I remounted my Admiral 600SP receiver and set up the gyro. I have about 30 flights without using it. I set this up in mode C on a 2 position switch to let me turn it off. Hope to fly tomorrow and check out some high alpha’s :)