Freewing 90mm F-22 Raptor - Official Thread

[dsmithwc04]

Have many of you set your CG aft of the recommended 150mm mark? I was thinking of going with 160mm perhaps?

[HornDogg]

Well, I'm late to the 8s F-22 party but I've done my homework! Done pretty much all the recommended mods structurally and beefed up the elevator servos... after getting it programmed enough for a maiden. Then I had to "fix" the right Elevator by reversing it to function properly... forgetting about my flaps>Elev mix. Between no rifgt elevator working, working opposite direction, not working at all with flaps but would work by itself, and insult to injury about 3 hours of YouTube videos and troubleshooting to figure it out (add in I'm setting this all up on my new iX20 radio... literally second plane on the thing). WHAT A LEARNING CURVE. But... it now functions properly. Should be confident enough for a maiden flight on Thursday. We'll see how it goes. Been flying the last 15 years pretty much all helis, drones and planes. Fun sized, aerobatic, 3D, scale and giant scale. All disciplines. This is the first official EDF/Jet. Game on!

Well... that didn't go good. Maiden was SUPER SQUIRELLY. ALMOST crashed it trying to get it stable. Did get it back in one piece. Second flight with adjustments... didn't get it back in one piece. 😕

Kinda got lucky... it rolled hard in a landing approach turn and spiraled down. Pancaked way out in the desert. Ripped one rear gear out and sheered the front one almost off. Gonna join the wait list for a new fuse and reevaluate this setup. I think my receiver and all that SAFE/AS3X stuff didn't help me much. Especially SAFE. It Turned so wide I barely could see it first flight. Sucks... but a part of the process. Also tweaking a HS-85MG shutter issue on the one reversed servo (elevator). Where do I even begin? 😳

[Luke89]

Nose gear steering - HELP PLEASE :)

Can anyone provide an exploded diagram of the 90mm nose gear servo steering linkage set up, had an incident & doing a main fuselage swap but no clue how the front nose gear all stitches together as I've lost half the pieces. Bought the screw set etc but not sure what horns and extras I need.

The manual does not actually show an exploded view. If anyone could provide up close pics or a link to some views I would be forever grateful :)

Also door linkage is it just the one at the front or does the nose steering also link to the doors at the rear side too?

Thanks :)

[xviper]

Well... that didn't go good. Maiden was SUPER SQUIRELLY. ALMOST crashed it trying to get it stable. Did get it back in one piece. Second flight with adjustments... didn't get it back in one piece. 😕

Kinda got lucky... it rolled hard in a landing approach turn and spiraled down. Pancaked way out in the desert. Ripped one rear gear out and sheered the front one almost off. Gonna join the wait list for a new fuse and reevaluate this setup. I think my receiver and all that SAFE/AS3X stuff didn't help me much. Especially SAFE. It Turned so wide I barely could see it first flight. Sucks... but a part of the process. Also tweaking a HS-85MG shutter issue on the one reversed servo (elevator). Where do I even begin? 😳

Please explain "SUPER SQUIRELLY".
Where to begin? I think if you are going to fix it, maybe you should begin at the beginning and keep it simple. Just because you have an IX20 doesn't mean you have to do the stuff an IX20 will allow you to do. Perhaps you were trying to do too much in terms of programming, SAFE, etc. This is not a hard plane to fly, nor is it a complex plane to set up. Maybe just set it up as a simple 6-ch plane, give yourself 3 different rates and some expo on all control surfaces. Don't worry so much about ELE to flap compensation. Slowing down the flap deployment to 2 seconds makes for less quirkiness. SAFE can be a real problem if you fly too fast (really big, wide turns) or too slow (weird stall characteristics) and particularly if the plane isn't trimmed properly when NOT in SAFE (make sure it's trimmed to fly "hands off" before activating SAFE). My 8s F-22 has no structural mods, no beefed up servos anywhere, basic 6-ch functionality, no ELE to flap comp, simple gyro set up. The maiden was like flying a slow trainer. Landing was like coming down on a marshmallow. The only "fancy" thing I've got on it, is reverse thrust to stop shorter.
Once you get a good maiden out of the way, then start doing "fancy" stuff with your IX. Perhaps those "beefed up" servos were not the ones to use. The stock ones don't shutter and no reversing is required. An 8s F-22 has more thrust but it really doesn't fly that much faster.

[xviper]

Nose gear steering - HELP PLEASE :)

Can anyone provide an exploded diagram of the 90mm nose gear servo steering linkage set up, had an incident & doing a main fuselage swap but no clue how the front nose gear all stitches together as I've lost half the pieces. Bought the screw set etc but not sure what horns and extras I need.

The manual does not actually show an exploded view. If anyone could provide up close pics or a link to some views I would be forever grateful :)

Also door linkage is it just the one at the front or does the nose steering also link to the doors at the rear side too?

Thanks :)

Mine is put away for winter. Try looking at this threads photos. Go to top of page and click on "photos". There might be something there that shows you what you need.

[Evan D]

I agree 100%. When rebuilt make it simple. The plane flies great with no stabilization at all. It also flies great set up 6ch with no fancy mixing and with standard flaps needs no elevator compensation. And book CG works for the first flights. It's an excellent first EDF.

Just because others have all the fancy mixing doesn't mean it's a good thing on a first EDF on it's first flights.

The only thing I would suggest is MAYBE a steering gyro as the F-22 has an odd knuckle in the main gear suspension. I suggest this Assan AG61 Anti-sideslip Front Steering Wheel Gyro (rc-castle.com)

Please explain "SUPER SQUIRELLY".
Where to begin? I think if you are going to fix it, maybe you should begin at the beginning and keep it simple. Just because you have an IX20 doesn't mean you have to do the stuff an IX20 will allow you to do. Perhaps you were trying to do too much in terms of programming, SAFE, etc. This is not a hard plane to fly, nor is it a complex plane to set up. Maybe just set it up as a simple 6-ch plane, give yourself 3 different rates and some expo on all control surfaces. Don't worry so much about ELE to flap compensation. Slowing down the flap deployment to 2 seconds makes for less quirkiness. SAFE can be a real problem if you fly too fast (really big, wide turns) or too slow (weird stall characteristics) and particularly if the plane isn't trimmed properly when NOT in SAFE (make sure it's trimmed to fly "hands off" before activating SAFE). My 8s F-22 has no structural mods, no beefed up servos anywhere, basic 6-ch functionality, no ELE to flap comp, simple gyro set up. The maiden was like flying a slow trainer. Landing was like coming down on a marshmallow. The only "fancy" thing I've got on it, is reverse thrust to stop shorter.
Once you get a good maiden out of the way, then start doing "fancy" stuff with your IX. Perhaps those "beefed up" servos were not the ones to use. The stock ones don't shutter and no reversing is required. An 8s F-22 has more thrust but it really doesn't fly that much faster.

[Evan D]

I'm sure mine is but... How you check your CG makes a difference, gear up, gear down, plane right side up etc. And how I like mine to fly may not be how you do. My suggestion is to balance it more or less by the book (more or less since the F-22 is not sensitive to CG at all) and then fly it and adjust to your preference.

Have many of you set your CG aft of the recommended 150mm mark? I was thinking of going with 160mm perhaps?

[HornDogg]

I agree 100%. When rebuilt make it simple. The plane flies great with no stabilization at all. It also flies great set up 6ch with no fancy mixing and with standard flaps needs no elevator compensation. And book CG works for the first flights. It's an excellent first EDF.

Just because others have all the fancy mixing doesn't mean it's a good thing on a first EDF on it's first flights.

The only thing I would suggest is MAYBE a steering gyro as the F-22 has an odd knuckle in the main gear suspension. I suggest this Assan AG61 Anti-sideslip Front Steering Wheel Gyro (rc-castle.com)

Will do. I did a TON of research on this frame and setup and I think I got too much info to start by doing so. No fuselage in stock so this one will sit for a bit until I can fix it. I'll be back to my gassers I guess. Had hoped to use this for the winter. Thanks for the info guys. I did put the right Elevator on a separate channel for future setup but outside of that, the only big adjustment was the AS3X/SAFE stuff. Will scrub the Co fig top to bottom. And recommendations on rates/expo?

[dsmithwc04]

I'm sure mine is but... How you check your CG makes a difference, gear up, gear down, plane right side up etc. And how I like mine to fly may not be how you do. My suggestion is to balance it more or less by the book (more or less since the F-22 is not sensitive to CG at all) and then fly it and adjust to your preference.

Good call on CG method.

I actually think I had it WAY nose heavy. I decided to try inverting the plane in my CG stand which allows much easier measurements. With gear down I had to move the batteries back 1 full inch to get it to CG @ 150mm. My CG stand does not like the shape of the underside apparently because I got pretty consistent results albeit none of them were accurate until I inverted her on the CH stand.

[Evan D]

The book rates were good for me to start. Expo is personal preference but I use a template on new models with 20/30/40 or 20/40/60 on elevator and aileron and no expo usually on rudder (that's a leftover from hovering 3D planes). I do have 20/30/40 on pitch, 20/40/60 on aileron and no expo on rudder.

Some say this has good pitch and roll authority but I found I wanted a bit more (I also have both tailerons and full span ailerons on high rate but with the bit more expo). I absolutely agree that the rudders are super effective so be careful with them, if you typically use expo on rudders use the 20/30/40.

Will do. I did a TON of research on this frame and setup and I think I got too much info to start by doing so. No fuselage in stock so this one will sit for a bit until I can fix it. I'll be back to my gassers I guess. Had hoped to use this for the winter. Thanks for the info guys. I did put the right Elevator on a separate channel for future setup but outside of that, the only big adjustment was the AS3X/SAFE stuff. Will scrub the Co fig top to bottom. And recommendations on rates/expo?

[Evan D]

Let me add that I have a ton of planes (over 100 planes ready to go that I cycle through) so I make it easy on myself. Once I figure out where I like the balance I figure out a very easy way to check it with it sitting on a bench on its wheels and upright. For example on this I have a specific panel on the leading edge I know to pick it up with index finger tips to check it. Then I write and/ or draw a picture of exactly where that is on the underside of the canopy. Again, for this plane it's a drawing to that panel on the wing.

On other planes it may be a tail sit test or some other easy way to check it. On some planes I also put a piece of scotch tape with a line and battery size and stick it on the side of the battery compartment, some planes have multiples if I use different size or weight packs. On this I have two such markings as I use a 5200 set of batteries and sometimes a 6000 set (in addition to the panel spot to do a quick CG check). What I don't want is to need a ruler to make an actual measurement since I don't carry one to the field.

Hope that makes sense.

Good call on CG method.

I actually think I had it WAY nose heavy. I decided to try inverting the plane in my CG stand which allows much easier measurements. With gear down I had to move the batteries back 1 full inch to get it to CG @ 150mm. My CG stand does not like the shape of the underside apparently because I got pretty consistent results albeit none of them were accurate until I inverted her on the CH stand.

[HornDogg]

The book rates were good for me to start. Expo is personal preference but I use a template on new models with 20/30/40 or 20/40/60 on elevator and aileron and no expo usually on rudder (that's a leftover from hovering 3D planes). I do have 20/30/40 on pitch, 20/40/60 on aileron and no expo on rudder.

Some say this has good pitch and roll authority but I found I wanted a bit more (I also have both tailerons and full span ailerons on high rate but with the bit more expo). I absolutely agree that the rudders are super effective so be careful with them, if you typically use expo on rudders use the 20/30/40.

Thanks. I'll copy my current setup, wipe out all the SAFE (OXYMORON) crap and setup basic configuration and wait for a fuse. Thanks! I did setup the book throws then expo but also setup 3 flight modes... maybe they had too much throw? I'll dial em back some...

[HornDogg]

Please explain "SUPER SQUIRELLY".
Where to begin? I think if you are going to fix it, maybe you should begin at the beginning and keep it simple. Just because you have an IX20 doesn't mean you have to do the stuff an IX20 will allow you to do. Perhaps you were trying to do too much in terms of programming, SAFE, etc. This is not a hard plane to fly, nor is it a complex plane to set up. Maybe just set it up as a simple 6-ch plane, give yourself 3 different rates and some expo on all control surfaces. Don't worry so much about ELE to flap compensation. Slowing down the flap deployment to 2 seconds makes for less quirkiness. SAFE can be a real problem if you fly too fast (really big, wide turns) or too slow (weird stall characteristics) and particularly if the plane isn't trimmed properly when NOT in SAFE (make sure it's trimmed to fly "hands off" before activating SAFE). My 8s F-22 has no structural mods, no beefed up servos anywhere, basic 6-ch functionality, no ELE to flap comp, simple gyro set up. The maiden was like flying a slow trainer. Landing was like coming down on a marshmallow. The only "fancy" thing I've got on it, is reverse thrust to stop shorter.
Once you get a good maiden out of the way, then start doing "fancy" stuff with your IX. Perhaps those "beefed up" servos were not the ones to use. The stock ones don't shutter and no reversing is required. An 8s F-22 has more thrust but it really doesn't fly that much faster.

From takeoff and the first roll to climb and get into pattern, the plane rolled very aggressively... had to quickly adjust. While tweaking trim it was decent in forward flight, barely, but elevator was a little off. Couldn't get it tweaked well enough for fighting to keep it steady in turns. Tried lower rates, SAFE.. no real improvement. SAFE numbed aileron so much my turn was humongous. We'd have a new president by the time it completed a 180. So I disabled SAFE and opted to manually fight it back to the ground. Took work. But it was safely landed. Made some SAFE adjustments, tweaked expo, and tried a flight again. Nothing crazy. Just basic steady flying. Was worse than before. Extreme hard turns and rolls. Full battle start to finish. Thanks for the recommendations. Only the elevator servos were swapped for MG and stiffer push rods used that I made. Other than that, it's all programming

[xviper]

From takeoff and the first roll to climb and get into pattern, the plane rolled very aggressively... had to quickly adjust. While tweaking trim it was decent in forward flight, barely, but elevator was a little off.

Was this roll all by itself or overly sensitive aileron stick? I'll consider that it did it all by itself. To me at least, that would suggest one of several things - a loose control surface, something going on with another control surface (like flap or one of the elevators), wing warpage or poor alignment, something going on with the gyro. I had a plane years ago that had a very difficult aileron trim. Turned out one of the flap control horns came unglued. You also said that one of the elevator servos was shuttering. That may have had an effect in flight. The AS3X/SAFE gains, priorities, direction may have been a bit "off". (Additionally, when the gyro is acting on one control surface such as your elevator, having one normal and one with a reverse on it, could be problematic or peculiar.) Trimming when in SAFE is not very effective, if at all. Also, when trimming is done in AS3X, you must go "hands off" for a "3 count" for the trim to take effect. In your situation, it sounds like you didn't have 3 seconds to go hands off, so trimming likely had to be excessive and probably didn't work too well.
As said, when you start again with this plane, go the KISS principle at the beginning.

[xviper]

wipe out all the SAFE (OXYMORON) crap

I got a grin out of that one. I fly with a fellow who only flies in SAFE. On the most part, this has worked out for him but once in a while, it has bit him in the butt. He finds it easy because there's little need for trimming as SAFE flies the plane for him within a certain trim envelope. He doesn't really modulate his stick movements to speak of, just jambs his sticks to each limit. So long as his plane is set up out of the box within that "trim envelope", it flies to his satisfaction. BUT, along comes a plane that isn't set up within that trim envelope and a crash is virtually guaranteed. 10% to 15% of his planes go from box to ground within 10 seconds from throttle up. Nevertheless, he is getting better over time and numbers of planes.

[HangarQueen]

Just my 2 cents here...
you didn't mention if you are using tailerons, or traditional elevator and ailerons configuration? Tailerons gives it more roll authority, so go easy on the aileron part in that mix.
If turns are too wide, are you using enough rudder in the turns?
Agree with the others that flap compensation is not necessary on this one. I have slowed down the flaps for 2 seconds to full, and have done around 60 flights without any flaps to elevator compensation. I can go from clean to full flaps without even touching the stick, it won't move.
To find out if you have correct CoG in flight, do a 45° dive test.
I started marking the CoG by inserting thumbnails (and gluing them in), which gives a great tactile feedback when picking up the model with your fingers. And I agree that this model isn't picky about CoG (or weight).
I just had to replace the elevator servos on mine, as the original ones started shuddering a bit too much to my liking, might be the potentiometers going bad. Don't know and don't care what it is, but not taking any risk with that. Replaced them with Hitec 85MG ones, but had to adjust programming for the right elevator (reverse). As I also moved to a new radio, I had to check all mixes and settings too, so that is a good incentive to do a thorough check of the model. No more shuddering on elevator servos, and a bit less play on them too.
Avoiding any discussion about using stabilization or not, to each his/her own, but if you do use it, do at least one trimming flight without stabilization (because it masks bad setups).
Regarding takeoff runs: beware that the landing gear is prone to the gear legs getting some play, and that will make you work to keep it on the centerline. Again, steering gyros might mask that, so make sure you check them regularly for any play, and apply threadlock or similar to those hex screws.

[Evan D]

"I did put the right Elevator on a separate channel for future setup..."


My recommendation to keep it simple and not use AS3X was for the first flights. To me it really sounded like his issue was radio set up or improper AS3X settings.

[HornDogg]

Just my 2 cents here...
you didn't mention if you are using tailerons, or traditional elevator and ailerons configuration? Tailerons gives it more roll authority, so go easy on the aileron part in that mix.
If turns are too wide, are you using enough rudder in the turns?
Agree with the others that flap compensation is not necessary on this one. I have slowed down the flaps for 2 seconds to full, and have done around 60 flights without any flaps to elevator compensation. I can go from clean to full flaps without even touching the stick, it won't move.
To find out if you have correct CoG in flight, do a 45° dive test.
I started marking the CoG by inserting thumbnails (and gluing them in), which gives a great tactile feedback when picking up the model with your fingers. And I agree that this model isn't picky about CoG (or weight).
I just had to replace the elevator servos on mine, as the original ones started shuddering a bit too much to my liking, might be the potentiometers going bad. Don't know and don't care what it is, but not taking any risk with that. Replaced them with Hitec 85MG ones, but had to adjust programming for the right elevator (reverse). As I also moved to a new radio, I had to check all mixes and settings too, so that is a good incentive to do a thorough check of the model. No more shuddering on elevator servos, and a bit less play on them too.
Avoiding any discussion about using stabilization or not, to each his/her own, but if you do use it, do at least one trimming flight without stabilization (because it masks bad setups).
Regarding takeoff runs: beware that the landing gear is prone to the gear legs getting some play, and that will make you work to keep it on the centerline. Again, steering gyros might mask that, so make sure you check them regularly for any play, and apply threadlock or similar to those hex screws.

Thanks! It was a basic elevator setup. Hadn't done tailerons yet. CG was close if not spot on. Using 6000mah dual 4s Admiral packs...

[TangoVector]

I just pulled the trigger on an ARF+ that will get my FMS 8S fan and 3D printed thrust vector nozzles. Now time to scroll through 200 pages for useful information.

[Evan D]

Good choice! There’s a lot of info. Ask questions.