Twin 50mm EDF Mig 29

SSgt Duramax

Junior Member
I'll just be glad to get one of my planes to actually fly. The B-17 is a store-bought plane, so it doesn't count. My Nieuport cowling is repaired & I will try again. I've gotten them to fly (somewhat) as a crude glider at least.
Perhaps that's what everyone is waiting for, to see one of my planes actually fly a decent distance.

:unsure::unsure::unsure::unsure::unsure:
You build WWI planes though, and those look pretty hard to build. They have never really been my thing, but I am thinking about building one. I think the Fokker D.VIII is cool, it was a plane I didn't really learn about until recently.

Looks like an easy fold/sculpt model.

I'll have to break out a photo of my first build.... 58" cardboard thing. That was before I discovered some of the methods used by FT, A-folds/B-folds, etc. It was a mess, but it was tough!

You should look into SPADs. They are neat!
 

Baron VonHelton

Elite member
You build WWI planes though, and those look pretty hard to build. They have never really been my thing, but I am thinking about building one. I think the Fokker D.VIII is cool, it was a plane I didn't really learn about until recently.

Looks like an easy fold/sculpt model.
You should look into SPADs. They are neat!

Leave it to me to pick the hardest planes on earth to get to fly.

:ROFLMAO:

The Sopwith Camel was so sensitive, more pilots died in training than in combat!

:oops:

Yes, the SPAD 7 & SPAD 11 & 16 ( a 2-seater!!) and the SPAD 13 are very stable platforms historically.

(y)

NASM-SI-2007-03435.jpg
 

SSgt Duramax

Junior Member

Beaver5150

Active member
Here's the cardboard thing I was talking about..... my first plane (ever), two years ago.
20201017_115601.jpg
....and a video. Elevator servo locked up during loops at end of flight, still nailed the landing! Turn volume down before viewing, its noisy!
 

SSgt Duramax

Junior Member
Update. Maiden completed. No matter what I did, I couldnt get the CG far enough back. I ended up taping a rock to the back and it flew at full up elevator ok.

I was only using 3S power as the battery was lighter. So good, I think I know where the CG is. Somewhere around where the V stabs start. I am obviously going to rebuild it, but I think this time with the motors in the rear of the plane. My propensity to avoid tail weight really bit me here.

I am going to update the plans with some minor changes and go from there.

20220416_140434.jpg
 

SSgt Duramax

Junior Member
I updated the plans by scaling them up and I also changed the entrance of the engine pods so that they don't suck in under power. They look less scale but I had to tear them off to fly it. The engines will be placed near the rear to help with CG.
 

newguy2012

Junior Member
Where were the motors to begin with? I am working over my F 15 and want to steal your design secrets! Sorry bout the maiden man. You will get there!
 

SSgt Duramax

Junior Member
Where were the motors to begin with? I am working over my F 15 and want to steal your design secrets! Sorry bout the maiden man. You will get there!
The back of them was even with the back of the wing or some where thereabouts.

I am guessing this is where the CG is. I was forward of there on the final flight, and I was able to keep it in the air long enough at mostly full elevator to determine it was a CG issue haunting me. You don't have a ton of aileron authority at max elevator when you do elevon mixing on a fighter come to find out.

mig29_01.gif
 

newguy2012

Junior Member
The back of them was even with the back of the wing or some where thereabouts.

I am guessing this is where the CG is. I was forward of there on the final flight, and I was able to keep it in the air long enough at mostly full elevator to determine it was a CG issue haunting me. You don't have a ton of aileron authority at max elevator when you do elevon mixing on a fighter come to find out.

View attachment 224188
In my limited experience the CG is always further forward on swept wings than you might think. On my 15 its barely behind the wing root. The version I released seems tail heavy testing in the garage. On yours I would bet your CG would be about a half inch further fwd than you think. Just my half a$$ opinion :)
 

SSgt Duramax

Junior Member
In my limited experience the CG is always further forward on swept wings than you might think. On my 15 its barely behind the wing root. The version I released seems tail heavy testing in the garage. On yours I would bet your CG would be about a half inch further fwd than you think. Just my half a$$ opinion :)
I would agree, but I've already tested and found that not to be the case. I was shocked it was so far back too. You have to remember the fuselage provides lift too. With the CG barely behind the wing root on this it just lawndarts.

I don't honestly know what is influencing where the center of lift is on this plane, but it is further back than it would seem logical. It would have been smart for me to make an unpowered glider and figure out on that. On Ben Harbers F-16 the CG is pretty far behind the LE of the wing as well.
 

newguy2012

Junior Member
I would agree, but I've already tested and found that not to be the case. I was shocked it was so far back too. You have to remember the fuselage provides lift too. With the CG barely behind the wing root on this it just lawndarts.

I don't honestly know what is influencing where the center of lift is on this plane, but it is further back than it would seem logical. It would have been smart for me to make an unpowered glider and figure out on that. On Ben Harbers F-16 the CG is pretty far behind the LE of the wing as well.
You will figure it out I am sure man. I made a glider version of the 15. Maybe take a step back? Just my 2 cents again.
 

Beaver5150

Active member
The back of them was even with the back of the wing or some where thereabouts.

I am guessing this is where the CG is. I was forward of there on the final flight, and I was able to keep it in the air long enough at mostly full elevator to determine it was a CG issue haunting me. You don't have a ton of aileron authority at max elevator when you do elevon mixing on a fighter come to find out.

View attachment 224188
I try to do a general CG mockup using just a rudimentary cut-out of the thing (same dimensions) on a piece of foamboard and checking aero-cg against actual CG by moving pack, motor, esc, and servos around to get a general idea of what to put where. Seems to be working so far. Then again, my airframes are much simpler.
 

SSgt Duramax

Junior Member
You will figure it out I am sure man. I made a glider version of the 15. Maybe take a step back? Just my 2 cents again.
I am pretty sure I am close, it flew (although still very nose heavy) about 3/4 inch forward from where I have it marked. I couldn't push the battery back anymore. My last crash was the day ender, so I wasn't able to tape anymore rocks to the back lol.

I try to do a general CG mockup using just a rudimentary cut-out of the thing (same dimensions) on a piece of foamboard and checking aero-cg against actual CG by moving pack, motor, esc, and servos around to get a general idea of what to put where. Seems to be working so far. Then again, my airframes are much simpler.

Yeah, i am going to finish putting the main plate together and toss it and see where it balances. I bet it is somewhere near where I think it is.
 
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Beaver5150

Active member
I am pretty sure I am close, it flew (although still very nose heavy) about 3/4 inch forward from where I have it marked. I couldn't push the battery back anymore. My last crash was the day ender, so I wasn't able to tape anymore rocks to the back lol.



Yeah, i am going to finish putting the main plate together and toss it and see where it balances. I bet it is somewhere near where I think it is.
Yeah, it took me a few builds to really get the hang of the "CG/ACG" balance.
First/last flying wing I built was a challenge. I actually ended up building forward of leading edge to get LiPo far enough forward to get things balanced. Was not what I intended, but it worked. (Stripped for parts/decommissioned)
 

SSgt Duramax

Junior Member
Yeah, it took me a few builds to really get the hang of the "CG/ACG" balance.
First/last flying wing I built was a challenge. I actually ended up building forward of leading edge to get LiPo far enough forward to get things balanced. Was not what I intended, but it worked. (Stripped for parts/decommissioned)
So just chucking around the base, i found the cg and marked it with a rock.

20220416_222546.jpg
 

SSgt Duramax

Junior Member
Nice. So I'm guessing, Edfs behind the spar, LiPo in the front near leading edge point above intake ducting? :unsure:
I'm scooting the engines back to the rear of the aircraft. the way the hatches work, construction, and where the battery needs to fit, it is pretty far forward. It is way easier to move the CG forward on this plane than back once it is all together.
 

SSgt Duramax

Junior Member
It flies spectacular. Turns out I was pretty dang close on my CG estimate. It is 7cm behind the leading edge of the wing, right in front of where the V Stabs start. I accidentally got a tail heavy flight in too, and the plane is still in one piece. It handles high alpha no problem. I am going to polish up the plans and submit it as a resource. This plane is the read deal now. With twin EDFs it goes vertical like a champ. Excess amounts of power, plenty of roll and pitch authority with the elevons. It doesn't need ailerons at all. Success!

Mostly finalized plans are updated here and submitted for a resource as well. Still don't have exhaust nozzles yet. We shall see what shakes out there.
 
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