Official Freewing JAS 39 Gripen 80mm EDF Jet

[xviper]

you are correct I do only want pitch control on the canards, but was under the impression I couldn't get that on my DX8G2 with stabilization, so just to mess around I thought about trying James' setup to see if I liked it.

regarding flaps - forgive me but for some reason I thought it was possible to do something like flaps if I offset the pitching down of the elevons with some pitching up on the canards. maybe that's too risky.

also, your response just made me realize what mistake I probably made- I think I probably plugged the first canard into aux1 and the second into aux2 which is why one isn't responding. I feel dumb. I'm going to go take a look to confirm my shame.

When I first got this plane, I had all control surfaces working together (pitch and roll on the canards) and all going through a gyro. I didn't feel it was needed (it also looked "too busy"), so I took some of it off. This is on a DX8G2.

[Cfreuen20]

That's smart. I like the exacto knife idea. :)

Well, anyway... time for some more ass-kickin' Gripen rippin'!

where do you get those missiles?

[Cfreuen20]

I thought you only wanted elevator (pitch control) on the canards? Next, why are you "deploying flaps"? There are no flaps on this plane, thus, the default flap switch needs to be INH. Also, flaps is usually defaulted to AUX1. He's got nothing plugged into AUX1. Somehow, you've got "flaps" and a switch coming into play in your TX. There shouldn't be any flaps or a switch to control them.

you are correct I do only want pitch control on the canards, but was under the impression I couldn't get that on my DX8G2 with stabilization, so just to mess around I thought about trying James' setup to see if I liked it.

regarding flaps - forgive me but for some reason I thought it was possible to do something like flaps if I offset the pitching down of the elevons with some pitching up on the canards. maybe that's too risky.

also, your response just made me realize what mistake I probably made- I think I probably plugged the first canard into aux1 and the second into aux2 which is why one isn't responding. I feel dumb. I'm going to go take a look to confirm my shame.

[Airguardian]

That's smart. I like the exacto knife idea. :)

Well, anyway... time for some more ass-kickin' Gripen rippin'!

[HockeyMac!]

Nicely done!
What strategy did you go with to pull the thing out in the end?

I took an exacto and cut the foam out around the plastic mount. I would then wiggle the mount to find where there was still glue and cut/remove until it wiggled out. As for the reinstallation, I used a dremel to shave down the sides so it could fit flush in the rear of the bay. Glue was applied to the wood tray and foam. It seems quite sturdy but we'll find out once the landings start happening lol. In the meantime, it seems like every gray I find is too dark a match for the Swedish colors :(

[xviper]

First, James has full aileron and elevator function on the canards with that mix. I thought you only wanted elevator (pitch control) on the canards? Next, why are you "deploying flaps"? There are no flaps on this plane, thus, the default flap switch needs to be INH. Also, flaps is usually defaulted to AUX1. He's got nothing plugged into AUX1. Somehow, you've got "flaps" and a switch coming into play in your TX. There shouldn't be any flaps or a switch to control them.
You can still do the ELE only on the canards if you use just the mix for ELE>AUX2 and ELE>AUX3, but then, you wanted gyro control on the canards and this will NOT allow that. You need to pick which one you want ........................... ELE on the canards or gyro control on them. You can't do can't do both with the RX you've chosen.

[Cfreuen20]

Hey guys, here is the Spektrum mixing on mine.

First, I have model setup for elevon in aircraft type:



then,
I have my left elevon in the ail port,
right elevon in the elevator port
right canard in aux 2
left canard in aux 3



It shouldn't truly matter which elevon is plugged into which AIL/ELE port or which canard is in which AUX port as the mixing will be similar as long as your 2 elevons are in the ail/ele ports and your 2 canards are in 2 aux ports. Once your there it's just playing within the mix as to going 100% or -100% and watching what happens.

So, you see my 4 mixes, 2 for ail, 2 for ele landed as such...



Again, I have the canards in aux2 and aux 3. I have mixed 1 elevon (from the ail port) mixed into both canards separately to control the roll, and 1 elevon (from the ele port) mixed into both canards separately to control the pitch. Here are each mix page:






I hope this helps, its really not hard at all. Within each mix all I did was set (elevon) > (canard) and move the rates to either full 100% or -100%. Took no more than 5 minutes.

She is all ready to fly tomorrow (had rain today). So excited to let you guys know how she goes and obviously videos will come soon afterwards.

I just can't seem to get this to work right, everything except the left canard seems to be functioning correctly. the left canard is not working for any pitch or roll functions, but it does function when I deploy flaps. however, the right canard doesn't function during the flap function. this confusing.

has anyone else experienced this?

[Airguardian]

I did quite a bit of work to keep the weight down, but also shift the CG further back. As you can see below, I flipped the nose gear around, ty airguardian for walking me through this

Nicely done!
What strategy did you go with to pull the thing out in the end?

[xviper]

I have an AR8360T and a DX8g2, and would prefer to have my canards set to pitch only. From what I've read in here, I can't stabilize the canards with the 8360 and that many people are adding a second gyro to control the canards. At the moment, I have a spare FT Aura 5 light sitting around, could this work for canard stabilization? could someone walk me through this setup?

otherwise, I'll just start things out with the setup James outlined early in the thread and I'm sure it'll work ok.

If you are wanting the canards to act in pitch only, you should just Y them together (use a servo reverser if necessary and I'm not sure you need to), plug them into an empty channel and do a mix (something like ELE>canard channel). Then put the gyro between the RX and the servos on that line. I use the Aura 5 lite for my flying wings, so it's set for "elevon" while the TX is set for "normal" wing. If you use the Aura, it's going to have to be set for "normal" wing and have the Y plugged into the empty port you use for the canards, however, since your RX is set to "elevon", this could create an undesirable situation. You'll need to test this out thoroughly. The Aura also has to get power somehow and it usually gets power from the throttle plug, so not sure how you'd do that as I'm not sure that the canard servos will provide the necessary power to the Aura. Additionally, the Aura, being a flight controller that uses a RX signal (either a normal RX or serial RX), I'm not sure how you would get that signal to it.
You would be far better off to keep the Aura for some other future plane and get a cheap, basic gyro like the HobbyEagle A3-L (20 bucks) and put that between the RX and the canard Y.

[Cfreuen20]

I have an AR8360T and a DX8g2, and would prefer to have my canards set to pitch only. From what I've read in here, I can't stabilize the canards with the 8360 and that many people are adding a second gyro to control the canards. At the moment, I have a spare FT Aura 5 light sitting around, could this work for canard stabilization? could someone walk me through this setup?

otherwise, I'll just start things out with the setup James outlined early in the thread and I'm sure it'll work ok.

[HockeyMac!]

I did quite a bit of work to keep the weight down, but also shift the CG further back. As you can see below, I flipped the nose gear around, ty airguardian for walking me through this, added the light burner, cut two holes in the battery compartment so the battery sits further aft, and finally moved the ESC about 1 inch back from its present position. The ESC was by far the easiest here to do.

It's got 6 coats of minwax and I'm waiting for the paint to arrive and then will add the ordinance.

[PawPaw]

Found my solution with Futaba: My Gripen now has canard/aileron, canard/elevator, TV mixing, and A3L gyro on elevons only with my T10J. Took all 10 channels with the gyro mode switch, 9 without. Used all 6 mixes available in the T10J and a SBD-1 SBus decoder added to my R3008SB but it all worked out. Just need some decent maiden weather!

[Airguardian]

Avanti is a good recommendation.

[kallend]

Thanks for all your comments and suggestions. For the moment I will scrap the idea completely. I thought as the Gripen is labeled as "intermediate" it would be a good EDF to start with and to go with a custom EDF initially to slowly increase the flying abilities and skill. In reality I would most likely just brutalize it very quickly. I will come back to this once I feel save flying EDFs.

Apart from that I found some videos testing the thrust with varying results. Whats interesting about the FMS EDFs, if you look closely the 3.5kg thrust is for 7S (They just write 25v) which is not even in the recommended specs of the system.
https://www.fmsmodel.com/product/fms...-motor-pro/41/
One the other hand this test comes to exactly 3.5 kg with just 6S

https://www.youtube.com/watch?v=0Fz0lQG1lFs

This test only gets up to 3.1 kg thrust

https://www.youtube.com/watch?v=-1WqIuzTf-k

and another one come sto 3.35kg thrust

https://www.youtube.com/watch?v=0GZmPr904_w

Here is an interesting comparison of FMS and Freewing EDFs. So the timing seems seems to change a lot in terms of thrust.
https://www.rcgroups.com/forums/show...its-comparison

From your original post it was not clear that this is your first EDF.

In that case I retract my Sukhoi 35 suggestion and agree with Evan. Get a simple sport jet first, preferably an inexpensive one.

[kallend]

Thanks for all your comments and suggestions. For the moment I will scrap the idea completely. I thought as the Gripen is labeled as "intermediate" it would be a good EDF to start with and to go with a custom EDF initially to slowly increase the flying abilities and skill. In reality I would most likely just brutalize it very quickly. I will come back to this once I feel save flying EDFs.

Apart from that I found some videos testing the thrust with varying results. Whats interesting about the FMS EDFs, if you look closely the 3.5kg thrust is for 7S (They just write 25v) which is not even in the recommended specs of the system.

1. The "official" thrust values are generally obtained with bench power supplies, not battery packs, so there is no voltage sag.

2. The "official" thrust values are on open test stands, so there are no losses associated with ducting, turbulence from cheaters, etc.

3. So the only values that really matter are installed values in your specific plane, which may be as much as 15% (or even more) below the "official" values.

4. When comparing thrust values from different sources, it is important to know things like the brand, capacity and age of the battery pack, the air temperature (this makes a difference), the pack temperature (makes a huge difference).

5. I hesitate to specify "C" values of the pack, since these are mostly mythical numbers anyway.

6. The links to tests that you provided were not using laboratory grade measuring equipment - so take their accuracy with a small grain of salt.

[Evan D]

Welcome to the world of EDFs. I suggest a good flying sport jet first and then work your way up. Something like an Avanti. Use it out of the box and figure out where you want to go from there.

Usually jumping into a higher performing EDF leads to "future disappointment and regret".

[Sam78EDMO]

Thanks for all your comments and suggestions. For the moment I will scrap the idea completely. I thought as the Gripen is labeled as "intermediate" it would be a good EDF to start with and to go with a custom EDF initially to slowly increase the flying abilities and skill. In reality I would most likely just brutalize it very quickly. I will come back to this once I feel save flying EDFs.

Apart from that I found some videos testing the thrust with varying results. Whats interesting about the FMS EDFs, if you look closely the 3.5kg thrust is for 7S (They just write 25v) which is not even in the recommended specs of the system.
https://www.fmsmodel.com/product/fms...-motor-pro/41/
One the other hand this test comes to exactly 3.5 kg with just 6S

https://www.youtube.com/watch?v=0Fz0lQG1lFs

This test only gets up to 3.1 kg thrust

https://www.youtube.com/watch?v=-1WqIuzTf-k

and another one come sto 3.35kg thrust

https://www.youtube.com/watch?v=0GZmPr904_w

Here is an interesting comparison of FMS and Freewing EDFs. So the timing seems seems to change a lot in terms of thrust.
https://www.rcgroups.com/forums/show...its-comparison

[PawPaw]

Just curious…anyone flying the Gripen with canards and TV programmed with Futaba? I watched the canard mixing video for Futaba but I’m thinking adding the TV would exceed the allowable 6 mixes in the T10J? Thanks for your input!

[kallend]

The Su35 is one of those planes I find myself hovering over the buy button. It haunts me in a way, I've seen the model fly in person and it looks so good. And it seems really fun to fly once you grok the flight characteristics. I also have a few projects going already. Hopefully they will keep offering it for some time and I can eventually add it to my collection. For now I'll have to settle for Airguardian's entertaining flying.

So many other planes are announced, sold for a year or two, and then discontinued.

There's a good reason this Sukhoi is still selling after what, ten years?

[SanExup]

The Su35 is one of those planes I find myself hovering over the buy button. It haunts me in a way, I've seen the model fly in person and it looks so good. And it seems really fun to fly once you grok the flight characteristics. I also have a few projects going already. Hopefully they will keep offering it for some time and I can eventually add it to my collection. For now I'll have to settle for Airguardian's entertaining flying.