Originally posted by kallend
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Official Freewing JAS 39 Gripen 80mm EDF Jet
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Freewing A-10 turbine conversion: http://fb.me/FreewingA10TurbineConversion
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Originally posted by janmb View PostFirst of all, this is very well flown by Justin. I will definitely give you that.
An optimal setup would first of all be a far more neutral CG, slight DOWN pitch on canards, and slight up pitch on elevons. With correct CG, that setup will high alpha hands off. And without preventing the canards from doing their main job.
I made some modifications for flights 4&5: 2mm "down" on the canards, added more throw all around - max high rates, lowered the Expo to 30% to get rid of that "mushy" feeling. My CG is pushed back to the recommended area (as it was for maiden).
My thoughts:
This is one of the easiest jets to fly from Freewing...maybe the Avanti is easier, but for a military jet, it sure flies like a pattern ship! Locked in, on rails, and I think the little bit of down trim on the canards removed the tail-wag.
I also fly in the afternoon, and we normally have E to W winds here (right down the runway)....it sometimes gets funky on my eyes in that "3rd" turn to line up with the runway. I was trying to see the paint for orientation, but with a bright sun behind it, you come to realize that it looks like an "arrow" and is very easy to see what it is doing and of course the direction it is flying. (so zoom back mentally if you get disoriented - let it fly without trying to do radical corrections - ie. push down the nerves - and a little rocking of the wings tells you everything!)
I love the vertical of the stock system...of course I would trade off vertical for a little more speed for low passes...but hey, don't fly right after a turbine, and you won't feel the need to go faster! (But wouldn't this be awesome with the tiny jet turbine in there???? Buying lotto tickets this weekend!)
All I can say is that in 5 short flights, this is one of my all-time favorite jets! If you're thinking about one, get it, you will not be sorry!
Thanks to all for the tips, pointers, printed tail cone, etc. You guys are great! :)
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Originally posted by JLambCWU View Post
4th flight LIVE High Alpha/Slow flight demo.
This is my 4th flight on the model that I did LIVE on FB demonstrating the slow flight/High Alpha capabilities of the model at the stock CG location.
I also demonstrate the “flap” function I have set up on my canards using only 6 channels.
With almost 4000 views on FB already, I took the time to upload it to YouTube to be able to share it. UNFORTUNATELY this means there is a pretty low quality/frame rate off the live feed recording.
This is rocking the 4400mah 70C Roaring Top from RCJetWerx that allow for balancing on the factory CG marks on the jet, while also giving great power into the vertical out of High Alpha passes.
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Originally posted by Pogo View PostI had some time in the shop this weekend and began the planned modifications. Landing lights were added to the main gear (as the full size has) by bonding aluminum tubing to the struts with KB weld into which the LED's slide. Plastic tubing was used to hide the springs.
The silly nose light was removed and a bulb fitted to a door made from 'glass sheet to sort of replicate the real Gripen. After some trial and error I used pinned hinges and a spring from the Venom nose door to close it and then cut back the existing doors.
The struts and insides of the doors were painted white and the wheels got a bit of detailing, as did the exhaust nozzle with some weathering and a flat coat applied. The inside was covered with aluminum tape to enhance the LED 'afterburner" and the last inch or so painted to simulate a jet pipe. The 'burner is one of Gooniac's (thanks Ray!) and although not installed for the first 2 flights it's in there and working now and I think it's going to look great in flight.
Tom
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Originally posted by JLambCWU View Post
My own plan is to use more channels to try and combine down elevons with up canard and get it even closer to scale behaviour and looks, not because it's necessary, but because it's fun to try and see if it works, since it is a hobby.
The full size Gripen canards do a lot of things, they alter the airflow over the wing and they also work together with the elevons in pitch at subsonic speed. Could it be that the reason the canards are mostly pointing downwards on the full size machine is not only to help with airflow, but also to keep the aircraft from pitching up due to its unstable tail heavy configuration? Since it is a good design it is probably doing both.
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Originally posted by TangoVector View PostCould it be that the reason the canards are mostly pointing downwards on the full size machine is not only to help with airflow, but also to keep the aircraft from pitching up due to its unstable tail heavy configuration?
Freewing A-10 turbine conversion: http://fb.me/FreewingA10TurbineConversion
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Originally posted by JLambCWU View Post[URL=filedata/fetch?id=289331&d=1607378897]Being also as the REAL aircraft ALSO lands this way with canards deflected up, I HIGHLY recommend people try my setup with the MODEL.
You seem intent on keeping to miss the point.
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Well, you are claiming to have made the 'ultimate high alpha demo' which uses a CG setup that is not optimal as the canards need to be pitched up for the jet to hold there.
Mine still has that problem too as I couldn't shift CG far aft enough (now that I have a Jetfan, that is going to change).
Since you mixed the 'canard pitch-up trim' with the high alpha demo video, I think it is worth addressing so as not to cause confusion. ;)
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As the ring in front of the exhaust nozzle was omitted by Freewing I made one from a Red Solo Cup (there may be a song). Lines were scribed in the plastic and I sprayed it with a metallic finish although most photos show it the fuselage colour. The circumference was a little small so an additional piece was needed in the bottom. The silver blocks in the photo are the 34 grams of lead I added for the first flights.
Tom
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Originally posted by Pogo View PostAs the ring in front of the exhaust nozzle was omitted by Freewing I made one from a Red Solo Cup (there may be a song). Lines were scribed in the plastic and I sprayed it with a metallic finish although most photos show it the fuselage colour. The circumference was a little small so an additional piece was needed in the bottom. The silver blocks in the photo are the 34 grams of lead I added for the first flights.
Tom
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Full flight at high alpha. Well, pretty much.. This flight was with the gyro switched off because of the light wind this evening. I wanted to see how it did without stabilization. CG at 13 mm behind the factory CG. Gens Ace 5000 45C. This was flight number 42 on the Gripen. My other planes are feeling neglected...
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Originally posted by HaroldAnderson View PostFull flight at high alpha. Well, pretty much.. This flight was with the gyro switched off because of the light wind this evening. I wanted to see how it did without stabilization. CG at 13 mm behind the factory CG. Gens Ace 5000 45C. This was flight number 42 on the Gripen. My other planes are feeling neglected...
Freewing A-10 turbine conversion: http://fb.me/FreewingA10TurbineConversion
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