Official Freewing JAS 39 Gripen 80mm EDF Jet

[Airguardian]

Yes I had to cut a bit of foam and also adapt the space aft of the EDF so the duct transition would be more or less smooth.

[HockeyMac!]

Before the TV upgrade I had added 130g of ballast in the tail.

I hid it inside the vertical stab, also on the foam right below the rudder, being careful not to protrude into the duct and also inside the nozzle on the aft end.

I would recommend considering moving the EDF unit aft as much as you can. I managed to shift mine 2.5cm and that helped a lot.

How did you move the unit back? Cutting some foam? Thx!

[Airguardian]

15 at a minimum. ( :
I'm happier more aft.

[Evan D]

About 15 for me. Balance is balance, what battery doesn’t change the balance point.

[Roy M]

I have read thru the forum. Looks like consensus is to move CG aft of molded markers on the bottom wing by 15 to 20mm ? I will be using roaring top lipos 4400mah.

[McDaniel]

Thank you guys, I will try something...🤷🏻♂️

[Airguardian]

Before the TV upgrade I had added 130g of ballast in the tail.

I hid it inside the vertical stab, also on the foam right below the rudder, being careful not to protrude into the duct and also inside the nozzle on the aft end.

I would recommend considering moving the EDF unit aft as much as you can. I managed to shift mine 2.5cm and that helped a lot.

[kallend]

Hey

to be honest I am a little pissed about this product, I bought it without due diligence, my fault. If you dont need the TV unit you are kind of screwed with the impossible CG...
SO what is the best way to add that stupid ballast weight? Thank you for any tips

My heavy nozzle not only looks better, it can add up to 120g of tailweight (it has slots for inserting up to 60g of lead, invisible once in place, in addition to the nozzle's own weight).

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

[Evan D]

sorry, I did so I knew where they were but deleted the pictures after adding the TV.


Here is a post by someone else that did the same. RC Groups - View Single Post - Freewing 80mm JAS-39 Gripen

And John created a 3D printed tail cone that has spot to add weight. RC Groups - View Single Post - Freewing 80mm JAS-39 Gripen

[McDaniel]

When I built my first one the TVs were not available yet. I knew I'd want them so in the joining area at the front of the rear half of the fuselage I made three or four 1/4" tunnels and put a few oz of lead in them. I tack glued the rear onto the fuselage and when the TV became available I gently pulled off the rear part and put the TV rear part on. It still needed a half ounce which I put under the vertical stab.

On #2 which I left non TV iI cut slots in the tail cone and glued lead in the slots.

Don't be pissed, just get it balanced (most have a balance further back than the book number) and fly it, It is a really good plane. By far my favorite one.



.

Thank you, do you have a picture of your tunnels, so I can have a Idea where to start? I am a bit rusty with craftmanship...lol

[Evan D]

When I built my first one the TVs were not available yet. I knew I'd want them so in the joining area at the front of the rear half of the fuselage I made three or four 1/4" tunnels and put a few oz of lead in them. I tack glued the rear onto the fuselage and when the TV became available I gently pulled off the rear part and put the TV rear part on. It still needed a half ounce which I put under the vertical stab.

On #2 which I left non TV iI cut slots in the tail cone and glued lead in the slots.

Don't be pissed, just get it balanced (most have a balance further back than the book number) and fly it, It is a really good plane. By far my favorite one.



.

[McDaniel]

Hey

to be honest I am a little pissed about this product, I bought it without due diligence, my fault. If you dont need the TV unit you are kind of screwed with the impossible CG...
SO what is the best way to add that stupid ballast weight? Thank you for any tips

[Airguardian]

Smoke wingtip trails in slow motion are way too cool!

[Airguardian]

Clips without music:

[Airguardian]

A couple of solo flights doing TV aerobatics with smoke and the ground footage of the 'aerial photo session' with the DJI FPV ;)

[Airguardian]

Plus some more...

[Airguardian]

Aaaaand... about damn time!!

[jaldendifer]

I discovered today my left gear not fully retracting. Had the problem before and found bind in the main gear (knee) joint which wouldn't allow full extension of gear. This time I discovered the plastic gear mount had about 2 mm of up and down play, as the factory glue is no longer holding it solid. Those who are having problems might check it.

[kallend]

IRIS-T for the Gripen: https://www.thingiverse.com/thing:4706132

Sidewinders for the Gripen: https://www.thingiverse.com/thing:4653284

Forgot to add:

Underwing pylons for the Gripen: https://www.thingiverse.com/thing:4713773

[T- Elbert]

Great fix
simple and functional