Official Freewing JAS 39 Gripen 80mm EDF Jet

[Airguardian]

Having it only in pitch also helped with the roll stability in high alphas and landing. The small adjustments to aileron in these situations seemed to make the nose drop and the plane to roll a little making it feel "loose."

Yikes!
How could we have possibly had forseen that before we got our hands on the jet, right?

Don't want to say 'I told you', but... actually, YES I DO!
To the nay-sayers, take that one!

[kallend]

Sidewinders to fit the wingtip rails. It's in 4 parts for ease of printing on smaller printers.

https://www.thingiverse.com/thing:4653284

You're welcome.

[Colorc]

Yikes!
How could we have possibly had forseen that before we got our hands on the jet, right?

Don't want to say 'I told you', but... actually, YES I DO!
To the nay-sayers, take that one!

haha, i expected as much too. One of those things i had to do to give a personal detailed account to end the "what should i set my canards to do" debate. It wasnt hard for me as i am running a 8ch rx. I had the mixes set up and just turned the aileron to canard mixes off in a second to experience both with two batteries. If for some reason you can not program the canards for just elevator only, it wont be catastrophic.

[Warbirdfan29]

Maiden Flight today!

The Gripen flies nice without any problems setting by the book (low rates) and the CG at 130mm. No gyro. Battery: TURNIGY 6s 4.000mAh 60C Heavy Duty with 685g / no additional weight needed / as far back as possible. I f you want to fly a bigger battery trim weight will be needed in the back.
I´ve added an ACL flash and white position lights in the back, landing lights on the main landing gear and an LED-Centerburner from "the lightburner". Looks cool!!! :-)

[kallend]

Sidewinders to fit the wingtip rails. It's in 4 parts for ease of printing on smaller printers.

https://www.thingiverse.com/thing:4653284

You're welcome.

Photo

[HaroldAnderson]

Go vote for the Gripen 2021 calendar images and while you are there download some of the high resolution images for your desktop! They are too large to post here and may be copyrighted so I didn't include one but they are nice.

https://www.saab.com/sites/content/gripen-calendar-shootout-2021

[Reaper911]

Sidewinders to fit the wingtip rails. It's in 4 parts for ease of printing on smaller printers.

https://www.thingiverse.com/thing:4653284

You're welcome.

Thx Kallend !

[Airguardian]

Ok, my previous vids were only the warm-up, the serious stuff begins now!
Fasten your seatbelts, curves ahead!

This is AFTER boosting jet throws.

Also think some were complaining that I was not doing much music-video stuff as of late (not sure if here or on RCG?), well... rest assured, this one's for you! And the band is swedish again! ;)

[kallend]

I figure the pitot tube is very exposed, and based on past experience I expect it to succumb to hangar rash or grass damage before long.

So I made and posted a replacement against such time as this happens.

https://www.thingiverse.com/thing:4654706

(For some reason Thingiverse is rather slow bringing up pictures right now)

[Evan D]

Graphics on. After yesterday’s flights I added another 30g in the tail for a total of 80g.

*Please don’t use those numbers for your own builds since mine is very non stock.

[Mizer67]

How'd it fly for you on 8S Evan D ? I'm waiting on the TV unit to fly mine on 8S...no way I could balance it with 863 grams of batteries vs. ~600 unless I had a kallend nozzle.

Mine seems particularly nose heavy. I've got 81 grams in the tail after removing the metal shrouded fan I was using and that's just enough for 600 gram 4000's but it's still nose heavy.

[Evan D]

I maidened two yesterday. Both JF/ HET. Mine with the HK Plush 120HV his with a CC. Mine with 6+2 Hobby Star 5200 45C (850g), his with a Powerhobby 8S 5000 100C (765g). Mine with a Orange 12ch (using 10ch now waiting for the TVs), his with a Spektrum 9ch with AS3X off. Slightly different programing.

I got a maiden +2 more on mine. 2 clicks of aileron and flew absolutely great. Balanced on the wing marks (took 50g) felt nose heavy. Two other flights were flawless. Only thing to note was I have the canards doing both pitch and roll. Interesting with the canards off for roll the roll rate is the same, good roll rate on high rates.

First flight of his needed a lot of roll and a lot of pitch trim. He had added weight to balance at 130-133, I forget which. On the ground looking at surfaces the first thing I saw was he had canards trimming with the elevons, we turned that off and centered them. We re subtrimmed the elevons straight. Second flight he took it off and it immediately hung a right over the pilots stations. Trying to retrimmed while flying he kept losing orientation especially away from the sun, it was inverted more than right side up. I took over and got it trimmed and flew the rest of the pack. I have to say I have excellent eye sight and spatial awareness and was having a hard time away from the sun. I have zero problems with any other plane but the stock colors on this are difficult, my repaint wasn't at all... After the flight comparing trim and throws we couldn't see anything that would cause the panes to fly differently. My only thought is balance but I can't think 122 vs 130-133 would make that much of a difference. I seemed like AS3X was messing with the flight but he is sure it's both off and not set up.

Along with getting my graphics done today I added 30g under the vertical to balance at 132. That makes 80g total added to the tail which I assume will be close to the TV tail section.

Both had pretty much unlimited vertical and very good speed.

How'd it fly for you on 8S Evan D ? I'm waiting on the TV unit to fly mine on 8S...no way I could balance it with 863 grams of batteries vs. ~600 unless I had a kallend nozzle.

Mine seems particularly nose heavy. I've got 81 grams in the tail after removing the metal shrouded fan I was using and that's just enough for 600 gram 4000's but it's still nose heavy.

[KevinMar]

+1 for it being easy to lose orientation due to the paint scheme and design of the jet.
On another note, I had to butt my 5000mah pack right up to the back of the compartment even with a 100g 3D printed nozzle. Still feels nose heavy so I’ll have to make some other tweaks before I go fly it again.
3 flights on mine with full canards for the pitch and only about 20% throw for the roll. Roll rate isn’t the issue, roll authority is. I think it could use more canard on the roll to increase the authority at lower speeds.

[Airguardian]

The white missiles on wingtips help with orientation on mine but overall I find this jet much easier to see than the lighter-grey Freewing Hornet.
Now that one is difficult indeed!
With the Gripen I had no real problems so far other than landing way after the sun is gone and getting blinded out by the landing light, lol.

[SanExup]

Evan, pardon my lack of knowledge, but what is a JF/HET with an HK plush 120HV? I assume it's the fan and esc? I don't think I would go 8s yet, though unlimited vertical and speed sounds fun. But I am thinking of pulling the stock edf and replacing it with something with more power. I don't know what to look at, other than what others are using.

And are you settling on keeping the canards on pitch only? I know you are going with the TV but was wondering if you ultimately prefer the canards on pitch only with the fixed nozzle.

Congratulations on the maiden and your Gripen looks amazing!

I maidened two yesterday. Both JF/ HET. Mine with the HK Plush 120HV his with a CC. Mine with 6+2 Hobby Star 5200 45C (850g), his with a Powerhobby 8S 5000 100C (765g). Mine with a Orange 12ch (using 10ch now waiting for the TVs), his with a Spektrum 9ch with AS3X off. Slightly different programing.

[Evan D]

Thank you!

i will keep the canards in both pitch and roll, it’s soooo locked in that way.

JF is Jet Fan, a brand of fan and housing which, in my opinion, are the best value in fans, work well and not too crazy expensive. HET is a brand of motor that works really well with the JF units. HK is Hobby King and they have a really nice 120A 8S capable ESC for about $50 on sale.

I do a lot of 8S, have a lot of batteries for it, love the amount of power at a lower amperage. If you are keeping the Gripen stock, no TVs I think you’ll be happy. TVS are typically less efficient so 8S makes a bit more sense.

Evan, pardon my lack of knowledge, but what is a JF/HET with an HK plush 120HV? I assume it's the fan and esc? I don't think I would go 8s yet, though unlimited vertical and speed sounds fun. But I am thinking of pulling the stock edf and replacing it with something with more power. I don't know what to look at, other than what others are using.

And are you settling on keeping the canards on pitch only? I know you are going with the TV but was wondering if you ultimately prefer the canards on pitch only with the fixed nozzle.

Congratulations on the maiden and your Gripen looks amazing!

[SanExup]

Nice, thanks! So that fan and motor would be worthy on 6s as well? Or not a huge jump in performance from the stock unit? Thinking of pulling the stock unit and using it as an excuse to throw in an ARF. But of course want the boost in performance with the Gripen. All I'm going on is other people's remarks of it being light in thrust in stock form. It might be spring before I can fly mine, 20i nches of snow in two days. And the Gripen would look goofy with floats.

[Evan D]

The stock unit is a newer inrunner setup... not a bad unit all...

[Airguardian]

It's not bad, but it's not great either.

Plane destabilizes and drifts in yaw at the top of wide loops due to the lack of thrust making it lose too much speed, which is annoying.
Acceleration after maneuvers that bleed a lot of energy (such as high alpha) is painfully slow.
It flies and you can do stuff with it, but if you want to do things other than circle flying, I'd say get the ARF version and drop in a better combo from the get-go.

Plus you get to use the extra weight of better, more powerful and heavier EDFs instead of needing to add useless ballast to get a decent CG. ;)

[Husafreak]

Hey thanks for the feedback! I'll start asking around and hopefully find out one of my friends has a 3D printer :) As for the question of whether to use the canards in pitch and roll that was also a good discussion. Obviously it can go either way but I find that Airguardian's videos are very close to how I hope mine would fly, very scale like, but still nimble. This will be my first canard equipped aircraft and I see that it is a bit different than an aileron + taileron set up as the canards affect airflow over the wings. The roll rate looks adequate without them (not for rifle rolls though) and the stability in high alpha is probably enhanced without them. Anyway cool aerodynamic stuff. BTW nice last video Airguardian, nice flying, although I only watched the first two flights I'll probably watch the rest because of the music! Therion is already on my Spotify download "theatrical progressive metal". I'm looking forward to a deeper dive, most excellent ;)