Official Freewing JAS 39 Gripen 80mm EDF Jet

[Airguardian]

I'd argue advanced pilots would prefer the canards to work in pitch alone, ideally operated through a gyro but will work fine without it too.

[Mizer67]

I thought I needed two gyros to get canards and elevons stabilized but perhaps with an A3 Super I can use the A2 channel pass through and Y-ed canards to work in pitch only while having one gyro handle everything. That would certainly help simplify the setup.

[janmb]

I thought I needed two gyros to get canards and elevons stabilized but perhaps with an A3 Super I can use the A2 channel pass through and Y-ed canards to work in pitch only while having one gyro handle everything. That would certainly help simplify the setup.

Without having any direct experience with the A3 super, based on the spec I would assume that to be possible indeed.

Otherwise, the Aura 8 might be a good alternative - a bit more pricey, but very capable.

[Reaper911]

You can also use Spektrum rx with AS3X it will apply gyro settings to mixed channels. That’s how I’m doing mine however only using canards for pitch control. I don’t like scale airplanes that roll like drill bits lol

[xviper]

I thought I needed two gyros to get canards and elevons stabilized but perhaps with an A3 Super I can use the A2 channel pass through and Y-ed canards to work in pitch only while having one gyro handle everything. That would certainly help simplify the setup.

That's one way to do it. That's how the SebArt Mig29's do it but they have TV nozzles as well.

[Reaper911]

Going to use the new Spektrum AR8360T with forward programming and have Canards set for pitch only. This will give me AS3X on all surfaces including TV.

[Robert Belluomini]

Going to use the new Spektrum AR8360T with forward programming and have Canards set for pitch only. This will give me AS3X on all surfaces including TV.

Please post video.

[Reaper911]

Please post video.

AR8360T not out until December. Also will wait for the TV unit to build model.

[kallend]

Going to use the new Spektrum AR8360T with forward programming and have Canards set for pitch only. This will give me AS3X on all surfaces including TV.

Same here. I'm willing to wait now the weather is getting iffy.

Also, roll input to the canards is not a good idea.

[RudyD54]

Same here. I'm willing to wait now the weather is getting iffy.

Also, roll input to the canards is not a good idea.

I was also planning to do the same but I’m coming across a possible issue with this setup. These forward programming AS3X receivers require setting up the wing and tail types in the transmitter in order to have gyro function on the flight surfaces. As per the documentation I’ve read, custom mixes are not supported for gyro stabilization. According to the Spektrum transmitter comparison chart I’ve linked below, the only current radios that support canards with elevons as a tail type are the IX12 and IX20; the difference being that the IX12 supports a single canard servo, and the IX20 supports dual canard servos. I have an IX20 so I thought I was all good and planned on setting up both canards on a Y for pitch to one of the canard outputs and then the TV nozzle on the other canard output, but it turns out that the canard with dual servo tail type does not actually exist in the transmitter. I opened a ticket with Spektrum to get some clarification because their feature chart clearly says this is supported. ( They also state origin mixing is available on both IX radios, but I can’t seem to locate that option either. )

My plan B is setting up the normal flight surfaces (elevons, canards, rudder) with the built in receiver gyro and using custom mixing for the TV nozzle. I’d then have to pass those outputs through a second independent gyro that would be strictly for the thrust vectoring but I’d much rather use a single gyro in the receiver if I can figure it out.

https://www.horizonhobby.com/on/dema...iter_Chart.pdf

[Quickstop]

I thought I needed two gyros to get canards and elevons stabilized but perhaps with an A3 Super I can use the A2 channel pass through and Y-ed canards to work in pitch only while having one gyro handle everything. That would certainly help simplify the setup.

Have you seen the new video of James flying with one simple gyro only operating on the elervons? Looked great and certainly didn’t look like it needed two gyros.

[xviper]

Have you seen the new video of James flying with one simple gyro only operating on the elervons? Looked great and certainly didn’t look like it needed two gyros.

I have to agree with this assessment. I don't think a gyro on the canards will add anything that a gyro on the elevons alone can do. A second gyro may be helpful if the VT nozzle were to be added but even then, it would only be beneficial if the Gripen has enough thrust to weight to actually hover with near zero airspeed and I'm not sure that it has that much power. Even if it did, with just one outlet, there would be no roll capability when hovering - can lead to a dangerous situation.

[kallend]

Have you seen the new video of James flying with one simple gyro only operating on the elervons? Looked great and certainly didn’t look like it needed two gyros.

I have a gyro on the elevons and VT nozzles on my Eurofighters, but not on the canards. Works well. Canards are pitch only, too.

[Mizer67]

Have you seen the new video of James flying with one simple gyro only operating on the elervons? Looked great and certainly didn’t look like it needed two gyros.

Yes, I saw it.

There wasn't any high AoA flying in the video that I recall, which is where I believe the jet would benefit most from a gyro on the canards and part of what's fun about the Mirage, Mig, etc.

I hope to be able to test this soon in flight as we're running out of "late October" next week.

I'm all for K.I.S.S. setups, so if there's no benefit, I'll remove the extra gyro/connection, but I've not flown a canard'ed delta and want to experiment to see what's a "best of" setup.

[Airguardian]

Have you seen the new video of James flying with one simple gyro only operating on the elervons? Looked great and certainly didn’t look like it needed two gyros.

It's not a matter of 'need'.
The jet does not 'need' even a single gyro so to speak.
But you can do extra stuff with them. One is cool. Two will be better if set up properly. ;)

I have to agree with this assessment. I don't think a gyro on the canards will add anything that a gyro on the elevons alone can do. A second gyro may be helpful if the VT nozzle were to be added but even then, it would only be beneficial if the Gripen has enough thrust to weight to actually hover with near zero airspeed and I'm not sure that it has that much power. Even if it did, with just one outlet, there would be no roll capability when hovering - can lead to a dangerous situation.

And I disagree with everything you said there.
Do as you please of course, I'll likely be dropping 3 gyros in mine.

[xviper]

There wasn't any high AoA flying in the video that I recall, which is where I believe the jet would benefit most from a gyro on the canards and part of what's fun about the Mirage, Mig, etc.

If I recall correctly my readings about canards from the Burt Rutan days of the Long EZ, canards were originally put on his planes to help prevent stalling when the AoA and airspeed got too excessive (high AoA, low airspeed). The canards would stall first, thus bringing the nose back down, helping to prevent the whole plane from stalling.
If these canards on the Gripen serve a similar purpose (aside from more maneuverability at speed), the canards will stall before the plane will. That being the case, in low airspeed, high alpha flight, the canards really don't contribute much anymore, so putting them on a gyro may not be of any benefit. If you really want to do really slow high alpha, the VT nozzle is the way to go and adding the gyro to that may be more effective.

[Reaper911]

I was also planning to do the same but I’m coming across a possible issue with this setup. These forward programming AS3X receivers require setting up the wing and tail types in the transmitter in order to have gyro function on the flight surfaces. As per the documentation I’ve read, custom mixes are not supported for gyro stabilization. According to the Spektrum transmitter comparison chart I’ve linked below, the only current radios that support canards with elevons as a tail type are the IX12 and IX20; the difference being that the IX12 supports a single canard servo, and the IX20 supports dual canard servos. I have an IX20 so I thought I was all good and planned on setting up both canards on a Y for pitch to one of the canard outputs and then the TV nozzle on the other canard output, but it turns out that the canard with dual servo tail type does not actually exist in the transmitter. I opened a ticket with Spektrum to get some clarification because their feature chart clearly says this is supported. ( They also state origin mixing is available on both IX radios, but I can’t seem to locate that option either. )

My plan B is setting up the normal flight surfaces (elevons, canards, rudder) with the built in receiver gyro and using custom mixing for the TV nozzle. I’d then have to pass those outputs through a second independent gyro that would be strictly for the thrust vectoring but I’d much rather use a single gyro in the receiver if I can figure it out.

https://www.horizonhobby.com/on/dema...iter_Chart.pdf

That's concerning let us know what you discover. Using a DX9 with AR9350 on my Havoc and gyro function works fine with all the mixing (normal, full span ailerons and crow. Don't understand why forward programming would change that? Might have to revert back to using an AR9350 and loose forward programming.

[RudyD54]

That's concerning let us know what you discover. Using a DX9 with AR9350 on my Havoc and gyro function works fine with all the mixing (normal, full span ailerons and crow. Don't understand why forward programming would change that? Might have to revert back to using an AR9350 and loose forward programming.

Absolutely will do once I get an answer from Spektrum and I'll post my setup in case anyone wants to use it as a reference. In the case of the Havoc, I believe it would work with forward programming and the gyro since the functions you have setup are more basic flight surfaces which are supported as wing and tail types in all the transmitter models that support forward programming. It's once you get into TV nozzles and canards that Spektrum seems to have not thought it out fully. (Granted, there don't seem to be many jets with dual canards and a TV nozzle using Spektrum gyros).

I don't have any experience with the AR9350 and I could be wrong, but it seems like you can setup mixes directly in the receiver using the AS3X programmer and those should be gyro stabilized or at least thats what it looks like from the AS3X programmer app that comes on the IX20.

[kallend]

I have an IX20 so I thought I was all good and planned on setting up both canards on a Y for pitch to one of the canard outputs and then the TV nozzle on the other canard output, but it turns out that the canard with dual servo tail type does not actually exist in the transmitter.[/URL]

I confirm Rudy's observation - the only iX20 option showing up with an elevon wing is canard with 1 servo output (you can have more than one servo, of course, by Y-ing them).

I thought I could finesse this by selecting "tailerons" to substitute for canards (since tailerons take both pitch and roll inputs) but that just makes the elevon outputs go screwy.

[Airguardian]

If I recall correctly my readings about canards from the Burt Rutan days of the Long EZ, canards were originally put on his planes to help prevent stalling when the AoA and airspeed got too excessive (high AoA, low airspeed). The canards would stall first, thus bringing the nose back down, helping to prevent the whole plane from stalling.
If these canards on the Gripen serve a similar purpose (aside from more maneuverability at speed), the canards will stall before the plane will.

Your recall of Burt Rutan's designs is right, but what follows is not. A wrong premise, leading to a wrong conclusion.
Modern fighter aircraft with canards, for the most part, are designed with different requirements and ideas in mind.
Those canards are not meant to stall before the wing does in the same way that smaller general aviation aircraft are thought to work out.

That is, high alpha and extreme maneuverability are not really in the 'requirements' of a Long-EZ or Varieze, lol.

That being the case, in low airspeed, high alpha flight, the canards really don't contribute much anymore, so putting them on a gyro may not be of any benefit. If you really want to do really slow high alpha, the VT nozzle is the way to go and adding the gyro to that may be more effective.

Couldn't be further from the truth :)
Good use of the canards will precisely be effective at low speeds by virtue of allowing the wing to stall at a higher angle of attack by means of deflecting the airflow and creating stable vortices. But I agree that when getting to the limit-scenarios with basically no speed left, the aerodynamics drop their authority and TVC takes over, so yes, the gyro on the nozzle will be very handy in super-slow flight, more so than the canards. But by not using the gyro on canards you will be missing a lot of other 'relevant' stuff that makes such a jet behave as scale (and well) as possible.