Official Freewing JAS 39 Gripen 80mm EDF Jet

[Radar-Guy]

Is the 200m maximum height you're referencing for the Gripen taken from a full speed straight and level pass pulled into a fully vertical climb out?

My Mig-21 on 6S with the FMS 2100kv fan will do about 200m climbs before stalling, so for me that'd be a good reference point.

Yes, it is. I have that FMS fan in my MiG-21 as well, the 8s Gripen gives a more agile feeling IMO.

[Evan D]

Somethings not right then. I have a JF with a HET 700-60-1738 that makes 98A and 2766 and I peter out at about 400ft. The other one I have flown has the HET 700-60-1865 making 119A and 3260W and it goes farther than I can see not slowing down.

When I do climbs I come across at about 2/3 throttle and then go full full throttle just before the pull to vertical.

[radfordc]

Been put off the Gripen by the post about it's alleged lack of power.

Just need someone to reassure me this Gripen is worth buying and not a white elephant

It's the most fun I've had with my pants on for some time!

[Skosh25]

Been put off the Gripen by the post about it's alleged lack of power. I just want to fly it scale like I am not that interested in tearing up the sky but if it is underpowered I might give it a miss, which is a shame because I have always like this model. I am not going to buy a model then buy a different motor to put in it. I am sure Alpha knows more then most about what motor wlll suit this model and he has been right on all the other Freewing models I own. Just need someone to reassure me this Gripen is worth buying and not a white elephant

I love my Gripen. Using a ~4000 pack or less is really the sweet spot on stock setup. If you can handle the shorter flight times it's a great jet.

[Mizer67]

Yes, it is. I have that FMS fan in my MiG-21 as well, the 8s Gripen gives a more agile feeling IMO.

Thanks Radar-Guy. Love fast and agile.

That Wemo setup looks perfect for me as I hate cutting foam and prefer to do as little modification to the airframe as possible.

I would be curious what thrust numbers you're seeing installed though if you have any. I agree with Evan D that I'd expect the 1865kv HET w/3300W on the Wemo to give closer to 1:1+ T/W settled.

[Evan D]

3.2kg thrust with a fish scale with the JF/ HET 1865kv.

[Radar-Guy]

Thanks Radar-Guy. Love fast and agile.

That Wemo setup looks perfect for me as I hate cutting foam and prefer to do as little modification to the airframe as possible.

I would be curious what thrust numbers you're seeing installed though if you have any. I agree with Evan D that I'd expect the 1865kv HET w/3300W on the Wemo to give closer to 1:1+ T/W settled.

Wemotec claim 3,75N bench thrust (serious tests at 3,7V). I stopped measuring static thrust with fish or kitchen scales a while ago after seeing too many doubtful results. My Gripen weighs in at about 3,5kg and I’m quite happy with the performance, but there’s no unlimited vertical performance (at least not with 8 deg C outside).

[Evan D]

Understood, all the numbers I’ve posted are ones we’ve taken. With the system installed in the plane on freshly charged everyday batteries.

[Captain Moron]

Never had a model with cannards before. Is it still possible to install a Hobby Eagle L 3 gyro to the Gripen or do the cannards pose a problem with fitting a gyro like the Hobby Eagle to the Gripen?

[Mizer67]

Never had a model with cannards before. Is it still possible to install a Hobby Eagle L 3 gyro to the Gripen or do the cannards pose a problem with fitting a gyro like the Hobby Eagle to the Gripen?

No problem with the canards in fitting a gyro. I think most have settled on a gyro only on the elevons and rudder.

I have an A3 Super 3 on mine. I couldn't get canard stabilization as well as stabilization on the elevons and rudders using just the A3 Super. I tried a few solutions on the canards only, but none I was satisfied with. It flies fine just like a normal delta w/o canards on the gyro.

[kallend]

Never had a model with cannards before. Is it still possible to install a Hobby Eagle L 3 gyro to the Gripen or do the cannards pose a problem with fitting a gyro like the Hobby Eagle to the Gripen?

A3L handles deltas just fine. Just use it on the elevons. The canards won't be a problem.

(I'm not using it on this Gripen, but I've used it on other deltas with canards.)

[Airguardian]

More Gripen fun!

[xviper]

No problem with the canards in fitting a gyro. I think most have settled on a gyro only on the elevons and rudder.

I have an A3 Super 3 on mine. I couldn't get canard stabilization as well as stabilization on the elevons and rudders using just the A3 Super. I tried a few solutions on the canards only, but none I was satisfied with. It flies fine just like a normal delta w/o canards on the gyro.

Did you try to X-link them to the elevons like Fred and I did?

[rms]

Bought a Gripen 2 weeks ago. Flies incredible good. Nice topspeed 194kmh slightly downwards. 180kmh level. Good controllable in high alpha. Nice and easy to land. Can do incredible short-field landings , use not to high alpha, but higer sink-rate and flair in the last 2sec.
- the CG is to far forward, wish the battery compartment more backwards.
- The power is ok, but may me to little for thrust vectoring, may be thats why its not available?
Did measure the trust to 2,4kg with a fish weight with a SLS 6s 3500 30c, took of the inspection "lid" under got 2,7kg. As long as it have speed it goes good. Doing som test and plan do modify for more thrust. Realy like this plane, wish I could get this in 12s with high performance.

Very much good info in this tread.

Video doing high speed and hige alpha landing.

Wish i could fly it more, but we hav got 20cm snow..so winter is on its way now.

[rms]

I have the Gripen in the box, waiting for TV-unit and my painting-skills to improve since it needs a Swedish livery. I have the Tigermeet M2000 and just love the option to power out of bad judgement at low altitude and I would really like the Gripen to be able to do the same and to accelerate in the vertical.
There seem to be a lot of knowledge and experience in this thread, so what do you suggest? Is it even possible? If 8S, any specific combos you think are good? Is 90mm an option or is the inlet or outlet area not large enough? Any ideas are welcome, except turbine, I'm not there yet

The Cg might be a problem with the 8s, you should get it in the air, it flys very good. And with the right mods it vill be a incredible plane.
90mm with TV might be the way to go. I did think of putting the fan unit more backwards id doing something like this. You will need more air into the fan.
Got from 2,4kg to 2,7kg thrust took of the box/ lid under the fan.

[kallend]

The Cg might be a problem with the 8s, you should get it in the air, it flys very good. And with the right mods it vill be a incredible plane.
90mm with TV might be the way to go. I did think of putting the fan unit more backwards id doing something like this. You will need more air into the fan.
Got from 2,4kg to 2,7kg thrust took of the box/ lid under the fan.

3D printed heavy nozzle can help with the CG. The one I posted can add up to an additional 60 to 120g of weight back there.

https://www.thingiverse.com/thing:4650359

[TangoVector]

Thank you all for more knowledge, this forum is great! After looking at different fan-combos, the HET 1865kv mated with a JF or Wemotec seems to be the most 80mm thrust available at the moment, as you guys already have found out. I'm looking at the FMS 90mm metal 1500kv, wondering how much thrust will be lost in the tight space in the Gripen after it has been shoehorned in there. It claims 4.9kg thrust at 29.6V/108A, equalling 3.2kW. That thrust will not happen with not enough airflow, but if it is capable of giving >4kg thrust, that would be interesting. But a lot depends on the airflow and how smooth surfaces that can be achieved and if it doesn't work, I have a perfect excuse to get myself an F22 ARF...

I know I will like it as it is, but future mods are always being planned. I have the Su35 and the M2000 and have visions of this one being the perfect mix of both. There's a good chance I just get the TV and be happy with that... or maybe not!

[Radar-Guy]

TangoVector I don’t think that it’s such a good idea to consider the FMS 90mm fan for the Gripen...

[Evan D]

Good morning is there any new word on the TVs James? I sent you a PM early last week but haven't heard. Hope this doesn't sound upset...

Hey guys, Happy Halloween. Just sitting down with a coffee and trying to catch up.

Evan D - You sound very upset and I hope all is well. But just send me a PM instead if you have a direct question. It's impossible for me to read through every thread looking for questions directed at me. I don't sit in front of the computer with the forums up and constantly refresh it. I bounce around.

I asked our warehouse manager about the Freewing container on Wednesday and all they said was it's looking like it should be here in early Nov now. That's all the info I have at the moment. I wish I could say it will definitely be here on Nov XX at 12:36pm CST but I can't. I have no idea if it is sitting in customs, if the train ran out of diesel or if the truck driver took a bad detour. It will be here as fast as possible.

"Late October" is an ETA, estimated time. If it shows up in early November, I am not sure that's cause for anger. I believe this to be the first Freewing pre-order container that we didn't come in early on since I have worked here. Either way, on Monday, I will surely call our web man Aros and have him update the website with whatever the latest info is at that time.

Now please, don't get upset if I don't respond here until Monday. It's the weekend and I have a big day of trick or treating and a night full of the wife and I eating our parent tax then a Sunday full of sick bellies and regret.

You will all be rippin your Gripen's soon enough. Have a great weekend everyone.

PS. I will also ask about the TV units, but spare parts don't get updated on pre-orders until the container arrives and all the new stock is sorted and checked in. The main reason we tell people who pre-order to not include parts is because it all arrives together, its quicker and more efficient to just ship the aircraft straight from the truck, but if they have to dig through all the parts then it that would cause more of a delay. Our warehouse also has to take all the pictures for the website of all those as well, just takes a bit of time when they also have all the other regular orders to be working through as well, but they do a pretty darn good job...I know I wouldn't want to do it.

[TangoVector]

TangoVector I don’t think that it’s such a good idea to consider the FMS 90mm fan for the Gripen...

Oh...

Thank you!