Official Freewing JAS 39 Gripen 80mm EDF Jet

[Gary S.]

RCMC the Gripen model is one that challenges one to think about flight dynamics a bit differently and inspires creativity in those that love it. Also Airguardian is a great resource for everyone.

[Airguardian]

I will blush!


I agree with the assessment of pitch-down trim on canards helping stability so we are on the same page, I was just being picky! ;)

[Airguardian]

There goes some more raw footage of the smokey Gripen, including that time I crashed due to abusing high alpha... :D

For the music video, watch this one instead (shared some time ago):

[Captain Moron]

Waiting for the lockdown to ease so I can maiden my Gripen. I have the cannards only set in pitch only. Is there any advantage to having the cannards set in roll has well or is it best to just have the cannards set in pitch only?

[Evan D]

There will be opinions... I like the quality of my roll better with some roll canards added.

[Skosh25]

Had a successful re-maiden today of the Gripen on 8S (JF/HET 700-60-1865). Had to battle 18mph winds and some snow piles on the runway, but noticeable difference in performance, both in vertical and overall speed. This really should have been a stock 8S jet IMO. My field elevation is 5400' and it performed beautifully. Packs came down quite warm @ 3.77 after 3 minutes (RT 4500 45C 4S). I was happy with the CG about 5mm behind the marks with the packs back as far as I could get them. Now time for paint.

[Swedraptor]

Hi,

I'm balancing my Gripen and I have read in this thread that many of you have a CG that are 10-20 mm behind recommended CG. The instruction manual says the CG should be 122 mm from the wing root but when I measure the molded markings they are actually 90 mm? What CG are you guys counting from? Shall I use for example 90+10 mm or 122+10mm? It is quite big difference.

Thanks! /Daniel

[Airguardian]

Forget about what the manual says, use the marks on the wings as reference ang go aft from there. The more aft the better.

It's super hard to move CG back on this jet, so chances that you end up being tail heavy are almost non-existent, lol

[kallend]

Forget about what the manual says, use the marks on the wings as reference ang go aft from there. The more aft the better.

It's super hard to move CG back on this jet, so chances that you end up being tail heavy are almost non-existent, lol

Heavy nozzle to help with CG adjustment:

https://www.hobbysquawk.com/forum/rc...348#post285348

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

[xviper]

Hi,

I'm balancing my Gripen and I have read in this thread that many of you have a CG that are 10-20 mm behind recommended CG. The instruction manual says the CG should be 122 mm from the wing root but when I measure the molded markings they are actually 90 mm? What CG are you guys counting from? Shall I use for example 90+10 mm or 122+10mm? It is quite big difference.

Thanks! /Daniel

That's probably because you are measuring from the wrong place. You are measuring from the front of the wing root where it attaches to the plane. The actual "wing root" they are talking about is where the molded part is on the fuselage. Just shoving a ruler up there while the plane is hanging, the mark on the wing is something like between 120 and 125mm from the fixed wing root. If I had the plane on the bench and I used a right angle triangle, it may very well be at the 130mm like it says on page 4 of the manual. Mine is balanced about 10mm behind the mark.
PS. I don't see anywhere in the manual about it saying "122mm". Where do you see that?

[Radar-Guy]

PS. I don't see anywhere in the manual about it saying "122mm". Where do you see that?

The silently revised manual...

https://www.hobbysquawk.com/forum/rc...335#post284335

[xviper]

The silently revised manual...

https://www.hobbysquawk.com/forum/rc...335#post284335

Hehe! Priceless! Then I measured it pretty close (120 - 125mm). Just gotta know where to measure from.

[Airguardian]

The mark under the wings is the same for all, thus why I insist to refer everything to that one.
Less chance of causing a misunderstanding.

[Hugh Wiedman]

RudyD54 with another flight on his Gripen on a windy, gusty day.

[BaltimoreBomber]

Just wanted to thank everyone in this thread for all the technical advice. I went nuts over this model, as its one of my top 3 favorite fighters. I ordered it, and everything else I could find for it!!!
So far I just got the Gripen in, I ordered Strobon V2's to upgrade all the lighting including adding the whit markers back by the tail cone, I ordered the F-22 Formation light kit to make these working as well, I found a company on aliexpress that had 6 thrust vectoring units left (already cleared customs will be here by the weekend), I ordered an RC Geek centerburner, and for my biggest change I just sent payment to Callie for 2 sets of graphics - one for splinter camo and the second which is going right on, the Aggressor graphics with Thor on the tail!
Cant wait to get this done... with some tricks you guys have come up with added in with my own. Looks like Ill be getting started next week.

one question for you all, what gyro/flight controller are you using with canards? I have a Jumper T18pro 5n1 so any receiver/controller combo is possible. I will prob use a Flysky IA-10B as Id like telemetry and 10 channels and Ive got a couple, unless you all recommend some better combo for stability.

[Evan D]

Very cool scheme. Welcome to the groups.

no recommendation on gyros, I don’t use them.

[janmb]

It's super hard to move CG back on this jet

No idea what you are talking about 😇

[kallend]

Just wanted to thank everyone in this thread for all the technical advice. I went nuts over this model, as its one of my top 3 favorite fighters. I ordered it, and everything else I could find for it!!!
So far I just got the Gripen in, I ordered Strobon V2's to upgrade all the lighting including adding the whit markers back by the tail cone, I ordered the F-22 Formation light kit to make these working as well, I found a company on aliexpress that had 6 thrust vectoring units left (already cleared customs will be here by the weekend), I ordered an RC Geek centerburner, and for my biggest change I just sent payment to Callie for 2 sets of graphics - one for splinter camo and the second which is going right on, the Aggressor graphics with Thor on the tail!
Cant wait to get this done... with some tricks you guys have come up with added in with my own. Looks like Ill be getting started next week.

one question for you all, what gyro/flight controller are you using with canards? I have a Jumper T18pro 5n1 so any receiver/controller combo is possible. I will prob use a Flysky IA-10B as Id like telemetry and 10 channels and Ive got a couple, unless you all recommend some better combo for stability.

I'm using an AR8360T which, with an iX20 and some finagling of the programming, allows built-in stabilization on all surfaces and the TV nozzles, with independent trims .

[Airguardian]

Gyros: I am using S8R (stabilized Rx) and GWS PG-03 but I wouldn't quite recommend these to you. PG-03 is not even manufactured anymore and S8R is mediochre to put it lightly.

No idea what you are talking about 😇

rofl

[radfordc]

No idea what you are talking about 😇

As Ricky said to Lucy...."esplain yourself!"