Twin edf SU-27

[Flitedesign 3d]

Welcome to follow another project of mine, a twin 70 mm edf su-27. Its one of the many planes I have always wanted to make. I have been working on the cad model and the sheets for the past two weeks. Its 9 sheets of foam, it has a wingspan of 1010 mm and a total lenght of 1460 mm. Im going as simple as possible with the controls, it will get only all moving stabs so only two servos. Here are a couple of renders, so thats how its supposed to look like. Now lets see what kind of pile of foam I will glue together.

 

[Merv]

Great looking plane

 

[GrizWiz]

Welcome to follow another project of mine, a twin 70 mm edf su-27. Its one of the many planes I have always wanted to make. I have been working on the cad model and the sheets for the past two weeks. Its 9 sheets of foam, it has a wingspan of 1010 mm and a total lenght of 1460 mm. Im going as simple as possible with the controls, it will get only all moving stabs so only two servos. Here are a couple of renders, so thats how its supposed to look like. Now lets see what kind of pile of foam I will glue together.

Amazing as always! 😊

 

[Monte.C]

Welcome to follow another project of mine, a twin 70 mm edf su-27. Its one of the many planes I have always wanted to make. I have been working on the cad model and the sheets for the past two weeks. Its 9 sheets of foam, it has a wingspan of 1010 mm and a total lenght of 1460 mm. Im going as simple as possible with the controls, it will get only all moving stabs so only two servos. Here are a couple of renders, so thats how its supposed to look like. Now lets see what kind of pile of foam I will glue together.

That looks fantastic. Amazing.

 

[Flitedesign 3d]

Slowly begins to take its shape, got the most boring job done which is the nose and the canopy, getting now to the more difficult part which is the engine ducts, they are a bit challenging because there are no formers inside to support the shape, Im overcoming that by removing the paper only on the curved areas near the intake.

 

[The Hangar]

Welcome to follow another project of mine, a twin 70 mm edf su-27. Its one of the many planes I have always wanted to make. I have been working on the cad model and the sheets for the past two weeks. Its 9 sheets of foam, it has a wingspan of 1010 mm and a total lenght of 1460 mm. Im going as simple as possible with the controls, it will get only all moving stabs so only two servos. Here are a couple of renders, so thats how its supposed to look like. Now lets see what kind of pile of foam I will glue together.

Awesome project!! Will there be plans? I've been wanting to make an su-30, but this is pretty close.

 

[Oldrover TJ]

Oh man...

My unmaidened Mirage may never fly if there are plans for this. Ever since @Mid7night released his F18 plans I've been itching to get a matching set of EDFs and now this.

Definitely looking forward to this build.

 

[AussieBison]

Amazing work man!
I might make a scaled down version with pusher props if that's feasible.

 

[AussieBison]

Please do keep the thread posted with more updates.. and pictures, and videos.
I have seen several places that offer F 14 / 15 / 16 / 18 plans. But SU / MIG, not as many!

 

[Flitedesign 3d]

I have done some great progress, only the tail and the leading edge extensions are missing. There are some 3d printed parts like the custom fan intake ramps, missile rails, tailcone and the stabilator- and servomounts. If everything goes well there will be a maiden tomorrow, the weather should be perfect like it has been lately. Its getting serious now!

 

[Monte.C]

I have done some great progress, only the tail and the leading edge extensions are missing. There are some 3d printed parts like the custom fan intake ramps, missile rails, tailcone and the stabilator- and servomounts. If everything goes well there will be a maiden tomorrow, the weather should be perfect like it has been lately. Its getting serious now!

It really is a masterpiece.

 

[Flitedesign 3d]

Awesome project!! Will there be plans? I've been wanting to make an su-30, but this is pretty close.

Yea the su-30 is really close, just slightly modify the leading edge extensions and and slap canards on it and thats it. A thrust vectored twin would be so cool wouldnt it? For the plans, there is this perpetual designers dilemma, after every iteration I want to make changes to the plans but if I do the reference pictures I take while building gets outdated. I guess cad model is the next best thing. But I will figure something out, luckily I have a lot more time now on summer

 

[Flitedesign 3d]

Im happy to announce that we have a successful maiden! I finished the build today by adding the tail and the leading edge extensions. I also added these extra intakes on the front, the real su-27 and most of the derived versions of it had these foldable intake grills to prevent stuff from getting sucked in on taxing, so sure enough Im using those as my advantage. Static thrust got increased by 200g. I planned to use 4 4s drone batteries at once since I have a lot of them but I kinda messed up the cg so Im using only 3. At least the wing loading is lower. Should have placed the fans 50 mm or so further back. Anyways, it flew really beautifully, feels really gentle in the air and it has a lot of power. A bummer it has only a flight time of about 2-2,5 minutes. I was supposed to fly two flights but unfortunately on the landing one of the pushrods got ripped out by the grass. Really easy fix though. Now the next step is to throw some paint and decals on this thing.

Oh and btw those mosquitoes really sucked...

Here are some numbers:
mass 1950g
thrust static 2350g at 120a about
wingspan:1010 mm (scale 1:14,5)
length: 1450 mm
edfs:12 blade
Batteries: 3x 4s 1,4ah 45c
esc: 2x hobbywing 80a
Servos: 2x emax es09md

 

[AussieBison]

Im happy to announce that we have a successful maiden! I finished the build today by adding the tail and the leading edge extensions. I also added these extra intakes on the front, the real su-27 and most of the derived versions of it had these foldable intake grills to prevent stuff from getting sucked in on taxing, so sure enough Im using those as my advantage. Static thrust got increased by 200g. I planned to use 4 4s drone batteries at once since I have a lot of them but I kinda messed up the cg so Im using only 3. At least the wing loading is lower. Should have placed the fans 50 mm or so further back. Anyways, it flew really beautifully, feels really gentle in the air and it has a lot of power. A bummer it has only a flight time of about 2-2,5 minutes. I was supposed to fly two flights but unfortunately on the landing one of the pushrods got ripped out by the grass. Really easy fix though. Now the next step is to throw some paint and decals on this thing.

Oh and btw those mosquitoes really sucked...

Here are some numbers:
mass 1950g
thrust static 2350g at 120a about
wingspan:1010 mm (scale 1:14,5)
length: 1450 mm
edfs:12 blade
Batteries: 3x 4s 1,4ah 45c
esc: 2x hobbywing 80a
Servos: 2x emax es09md

Good Job man! Absolute beast..
What paint scheme are you going for?

 

[Monte.C]

Im happy to announce that we have a successful maiden! I finished the build today by adding the tail and the leading edge extensions. I also added these extra intakes on the front, the real su-27 and most of the derived versions of it had these foldable intake grills to prevent stuff from getting sucked in on taxing, so sure enough Im using those as my advantage. Static thrust got increased by 200g. I planned to use 4 4s drone batteries at once since I have a lot of them but I kinda messed up the cg so Im using only 3. At least the wing loading is lower. Should have placed the fans 50 mm or so further back. Anyways, it flew really beautifully, feels really gentle in the air and it has a lot of power. A bummer it has only a flight time of about 2-2,5 minutes. I was supposed to fly two flights but unfortunately on the landing one of the pushrods got ripped out by the grass. Really easy fix though. Now the next step is to throw some paint and decals on this thing.

Oh and btw those mosquitoes really sucked...

Here are some numbers:
mass 1950g
thrust static 2350g at 120a about
wingspan:1010 mm (scale 1:14,5)
length: 1450 mm
edfs:12 blade
Batteries: 3x 4s 1,4ah 45c
esc: 2x hobbywing 80a
Servos: 2x emax es09md

 

[christ98406]

amazing

 

[TinymakerJackie]

Did you get bored with the f-14? for real I've been trying to mash the f-14 and su-27 together for a while now and here you built both!

 

[Oldrover TJ]

She flies beautifully, stable and yet maneuverable. You'd probably go faster if it wasn't for all the bugs!

 

[Flitedesign 3d]

Did you get bored with the f-14?

Yes the tomcat, let me just give some behind the scenes info here. Basically its just lacking its wingbox, it needs to be redesigned. There are three main problems with the current wooden version which are the material, the geometry and the hinge. The geometry is such that it is weak against torsion created by the center of lift far back in the swept postition. This makes the wings bend upwards in the swept position. This was a designflaw of mine. The problem with using wood as the material is that its youngs- and shear modulus (which basically determines the strain caused by stress and torsion) are 10-20 x weaker than carbon fibers, which is the perfect material for this application. But the density of cf is only about twice the birch plywoods. You see why wood isnt used in mechanical structures. This being said I just recently ordered a 2 mm carbon fiber sheet (hurt my wallet) and I will mill the parts out of that. The problem with the hinge is that in the current design the friction increases as force is applied to the wing. This is a problem because Im just using ordinary servos for the sweep, a linear actuator would be better but thats another story. Im trying to overcome this by using thin single groove ball bearings on the hinge, I have no idea if they will survive, the forces on them are quite significant even on a few g-forces.

So no, definitely not bored with the f-14, but since I have currently another very mechanical project, redesigning my custom corexy 3d printer, I wanted to make something that is mechanically very simple, like this su-27

 

[xinyue722]

That is awesome!!!!