Freewing A-10 1.7M Turbine Conversion 2 x P20-SX
08-06-2017, 09:32 PM
#26
Henke Torphammar has produced tons of conversion kits for hab.se for various freewing EDFs. I'm sure he would love to get onto this model as well.
89mm CG is getting close to being a bit aggressive, but probably should work just fine. I assume you don't plan to drain it below 25% tank anyway.
What is that weird sound on the video? I hope that is something from the camera/audio recording and not an actual sound from the turbine lol
As for heat while cooling, definitely be sure to park nose into the wind before stopping. Other than that I'm sure it should be just fine. If necessary, you could obviously also arrange to have an extra fan for it after parking. The clue is to have airflow through the nacelles so heat isn't allowed to build up and stay in one place.
89mm CG is getting close to being a bit aggressive, but probably should work just fine. I assume you don't plan to drain it below 25% tank anyway.
What is that weird sound on the video? I hope that is something from the camera/audio recording and not an actual sound from the turbine lol
As for heat while cooling, definitely be sure to park nose into the wind before stopping. Other than that I'm sure it should be just fine. If necessary, you could obviously also arrange to have an extra fan for it after parking. The clue is to have airflow through the nacelles so heat isn't allowed to build up and stay in one place.
the Sound is the audio of the phone , dont worry they sound great.
did some tests yesterday , if i shut down at 40% throttle the heat is gone fast.
i can use the old edf motors to cool them down :-)
08-13-2017, 07:36 AM
#28
Cool project. I have had my eyes on this one for a long time, but it takes forever until we can get kits here without spending $1000.I have not dug in to this one yet but my first aim would be doing it with no thrust tubes and fuel at CG. Looks promising with the weight numbers and twin P20's. I just posted in another thread that you can never get too much power.... but twin T35's in this one would be.....hm too much fun. I have two of those and only one T25 and one T15. Maybe will opt for another of the smaller ones for this twin as I really like my T35's sitting each in one plane. And I still have the FB Eurofighter 95% ready for twin Kolibri. hm.....
Looking forward to flight video. :-)
(I bet the 1050cc of fuel will be plenty, doing 9min in my 5kg Super Viper with 1100cc)
Looking forward to flight video. :-)
(I bet the 1050cc of fuel will be plenty, doing 9min in my 5kg Super Viper with 1100cc)
08-13-2017, 07:46 AM
#29
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Henke, what are your thoughts on idle thrust? In my experience, getting enough drag to slow down for landing tends to be a challenge - and a twin setup should be even more prone to such problems.
As for flight time, the avanti (let's call a spade a spade lol) is a lot less draggy, and is single engine.
I would guess max 4 minutes for this build.
Why would you build without thrust tubes? A-10s in general require dead weight in the nose. Pushing the turbines back is adding to the CG challenge I would think.
As for flight time, the avanti (let's call a spade a spade lol) is a lot less draggy, and is single engine.
I would guess max 4 minutes for this build.
Why would you build without thrust tubes? A-10s in general require dead weight in the nose. Pushing the turbines back is adding to the CG challenge I would think.
08-13-2017, 07:53 AM
#30
Might sound fun but $$$. If pipe needed I will add those but the initial aim would be without. But again thats only a guesstimate
08-13-2017, 08:08 AM
#31
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Pretty sure tubes are necessary. Without, the turbins must be very far back to allow for enough thrust angle.
A P20 build is really tempting, but outside budget atm
A kolibri build is out of the question for me - I like to fly, not spend half the time swearing 😂
A P20 build is really tempting, but outside budget atm
A kolibri build is out of the question for me - I like to fly, not spend half the time swearing 😂
08-15-2017, 08:21 AM
#32
First flight and landing
Well she fly,s
needed about 6 clicks up trim
in landing butterfly ailerons 10 mm up
comes very slow
take off in about 60 meters no flaps.
when flying full throttle it still wants to nose down a little so i am upping the pipes about 2 degrees more.
enough power at 50% throttle to fly around.
when going to full throttle she climbs away with good power.
landing was very slow amd impressive .
gear is exellent
3 minute flight incl startup 450ml on both engines
Take off
https://youtu.be/4cSDoio2_hw
landing
https://youtu.be/_VbaNHCKmmI
needed about 6 clicks up trim
in landing butterfly ailerons 10 mm up
comes very slow
take off in about 60 meters no flaps.
when flying full throttle it still wants to nose down a little so i am upping the pipes about 2 degrees more.
enough power at 50% throttle to fly around.
when going to full throttle she climbs away with good power.
landing was very slow amd impressive .
gear is exellent
3 minute flight incl startup 450ml on both engines
Take off
https://youtu.be/4cSDoio2_hw
landing
https://youtu.be/_VbaNHCKmmI
08-15-2017, 08:30 AM
#34
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Awesome - congrats 
And yes, you probably want another few degrees up thrust angle.
And dial down rates a bit more, especially the ailerons looked twitchy as hell.
And yes, you probably want another few degrees up thrust angle.
And dial down rates a bit more, especially the ailerons looked twitchy as hell.
Last edited by janmb; 08-15-2017 at 08:34 AM.
08-15-2017, 08:48 AM
#35
yes thrust tubes come out at 5 degrees.
i used you recomended settings.
on landing the idle
thrust is no issue at all.
so Henke feel free to make kits for it.
it works.
i used 2 avanti kits for mine and 2 outer rings used to vortex the thrust out at 5 degrees.
08-15-2017, 08:53 AM
#36
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Goodies
Looks a bit twitchy to me, but could obviously be conditions as well as fuel shifting I guess. Pretty common on maidens too anyway. Only the pilot can really know how it feels and that's the most important obviously.
Looked like it slowed down just fine too.
Temping as hell to copy this config to be honest
Looks a bit twitchy to me, but could obviously be conditions as well as fuel shifting I guess. Pretty common on maidens too anyway. Only the pilot can really know how it feels and that's the most important obviously.
Looked like it slowed down just fine too.
Temping as hell to copy this config to be honest
08-15-2017, 10:42 AM
#37
we thought so to but we are flying between trees with a good wind shear.
yes thrust tubes come out at 5 degrees.
i used you recomended settings.
on landing the idle
thrust is no issue at all.
so Henke feel free to make kits for it.
it works.
i used 2 avanti kits for mine and 2 outer rings used to vortex the thrust out at 5 degrees.
yes thrust tubes come out at 5 degrees.
i used you recomended settings.
on landing the idle
thrust is no issue at all.
so Henke feel free to make kits for it.
it works.
i used 2 avanti kits for mine and 2 outer rings used to vortex the thrust out at 5 degrees.
Behzad
12-13-2017, 05:37 AM
#41
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Hi all.
I saw the great results with this airplane A10 and twin turbines.
I start build the same plane with JatCat P20. But I am not used the thrust tubes. The turbines are little back and the test show me that CG position will be still OK. I used this turbine position in F86 or F100 before and work well.
F100:
F86:
And start with A10......
I saw the great results with this airplane A10 and twin turbines.
I start build the same plane with JatCat P20. But I am not used the thrust tubes. The turbines are little back and the test show me that CG position will be still OK. I used this turbine position in F86 or F100 before and work well.
F100:
12-14-2017, 03:56 AM
#42
Testing is knowing now we se Sandors A10 with tubes and it does great so that's the route. I've been doing a lot of conversions. The key is always to get the engine as far forward as possible. This talk about I can get CG anyway... sure but with extra batteries or lead in the nose. It's common a normal slap in conversion gets you like 1.5lb more take off weight, and that's allot when the engine only makes like 5.25lb. (Also it's common the thrust tubes add a little oumpf too)
I'm sure it will fly anyway, but it all is so much nicer if keeping it light making it pleasant rather then just a knee rattling experience. Enough stress running two turbines at once, no need for more... hehe.
I'm sure it will fly anyway, but it all is so much nicer if keeping it light making it pleasant rather then just a knee rattling experience. Enough stress running two turbines at once, no need for more... hehe.
Last edited by Henke Torphammar; 12-21-2017 at 01:05 AM.
12-17-2017, 06:56 AM
#45
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The last few posts here revolved around someone planning a build with aft mounted turbines and no thrust tubes - which in my opinion will definitely lead to CG challenges.
You definitely made the right call for turbine location on yours.
Really tempted to go the same route, but double micro turbines is so darn expensive.
12-17-2017, 09:37 AM
#48
https://aerobertics.be/en_be/mini-av...version-seb270
use my pictures as references , dont forget to make 2 extra pieces of tube to make a upwards thrust
if you dont :
1 . you melt your elevators
2. if you apply throttle it goes nose down
no need for brakes , its really slow at landing.
if you MUST get some china wheels with brakes , dont forget weight goes up fast!.
also i DO NOT fly with all the rockets and bombs under thr wings , i had terrible drag and poor handling on landing (lot of elevator needed in landing)
Last edited by digitech; 12-17-2017 at 09:40 AM.
12-17-2017, 11:16 AM
#49
My Feedback: (3)
Thank you. I have ordered from aerobertics before, very happy with their service.
Unfortunately, brakes are required here in the USA on turbine jets. Just the rules. Maybe a lightweight nose brake might be able to fit and satisfy the requirements.
I would keep mine light ... no cockpit, nothing under wings ... I just like to fly.
Unfortunately, brakes are required here in the USA on turbine jets. Just the rules. Maybe a lightweight nose brake might be able to fit and satisfy the requirements.
I would keep mine light ... no cockpit, nothing under wings ... I just like to fly.
