Scratch Built Su-35 Prop-jet

[philgabanski]

So I have wanted to build one of these prop-jets for a while. I see the FT-22 Raptor, the RcPowers series of parkjets, Josh trying to get an F-15 over 100mph and thought that looks awesome.

Where to start, so many great designs, which plane do I build? Which wing do I go with? KF, flat or airfoil? Ive wanted to do this for ages but where to start?

I decided on the Su-35 as I love the Russian art of high lift bodies and agility, they look unmistakable and menacing. I grabbed a 3 view off google and scaled it on graph paper making adjustments for the prop. I also decided to create a mild airfoil wing using 10mm Hobbyking xps foam as the base of the body/wings/LERX. It also gives some extra strength although at a cost of a ome weight. I also have 6mm depron so using this for all other areas.

I also used a 5mm carbon strip as a spar curved around to give some added strength.

Spec wise, it is a little smaller than what most other "semi profile" craft are:
Span 22inch
Length 32inch
Weight target <500g
Battery Nano tech 3s 1300mAh
Projected motor 28-22 1450kv
Prop 6x5
Possible switch to a fun fighter 1850kv later

Covering will be with Hobbyking wing tape as I like the strength it gives once heated!

So far so good!

 

[Jordan3367]

Cool! That looks good!
If you'd like some inspiration, here's an RC SU-37: https://www.rcgroups.com/forums/showthread.php?t=1070992
Not the same plane, but fairly close.

 

[RCman50]

This is cool! I've been in a prop-jet phase lately myself. My last 3 builds were prop-jets, SU-37(70%) an F-22 and the BluFO, all from MPF though. Can't wait to see this one! There so much fun to fly. Best of Luck.

 

[Fluburtur]

Russian jets are cool, especially the Sukhoi 27 familly.

I will be following this once closely!

 

[philgabanski]

Scored dome time so got stuck into the next section. Since I work too much, foam is great for getting models like this together quickly (relatively speaking)
I still remember building an F-16 pusher out of balsa only to write it off on the first hand launch. 3 months of building, you gotta have a sense of humour in this hobby!

 

[philgabanski]

Progress, hope it can fly! Reinforced the verticals with bbq skewers for some strength. Tape goes on, don't matter if there is a wrinkle or 2 as they come right out when hit with a heat gun!

 

[philgabanski]

Wow, new addiction I think!
These things track on rails, full spped low passes like 3 feet or lower and the speed is just blistering!!! The roll rate, although axial, was kinda rubbish. But given elevons only, to be expected. Could add ailerons but not really needed. Can some what do the cobra! Plenty of power from the foam fighters 1950kv motor, flying weight just on 430 grams.
This one isn't great at lower speeds , all be it in moderate gusts of wind, but super stable once you open up the throttle.
Need to build more of these!!! More, more I say!
Next time, build so speed controller is strapped externally for better cooling, move motor back about 20-30mm to allow balancing with slightly bigger battery. 1300 3s performed well although flights I limited to 4 to 5 mins to keep within range (I never discharge bellow 30% if i can help it)
The wing design worked, just 10mm hobbyking foam slightly aerofoiled.
Just need to finish the body work and give it a good clean up. (Rushed to finish and fly)

 

[Fluburtur]

Very nice! You need to show us videos of that beast!

 

[philgabanski]

https://www.youtube.com/watch?v=Y_gmXnc5ku8

Here is a video of the Sukhoi, One of my first vids so it's not great but gives an idea of how this thing goes.
It's hard to see because it's so small compared to other "parkjets"

 

[philgabanski]

So after the success of the small Su-35, I decided to build a bigger one, sort of. I decided to build an SU-34, scaled from 22" to 27" wing span.





Funny how quick you can bang one of these together after the first one.

 

[JimCR120]

I've built a couple prop-slot F-18's and boy are they fun. They turn heads too.

 

[philgabanski]

Video of the SU-34. I need to get a better camera for this.

 

[JimCR120]

Nice flying. Did you have someone with you recording or a hat cam?

 

[philgabanski]

Hat cam, need to get a better camera for it though, the foxeer does great on board recording (but with the agility of the SU-34, worried I'll spend all day up the paddock hunting for it) Once I get a better strapping system, I'll get some on board footage, should look good. With 160 degree view, it's too wide for hat cam but all I have at the minute.
Any how next project:


This is a balsa project I completed 6 years ago with limited success. With limited access to foam, I decided to build out of balsa. It lasted half dozen flights but was always hard to balance with the motor at one end and the battery at the other.
Enter my foam attempt at the Mig-31 Foxhound!



Su-34 was agile, this one is intended for speed!!!

 

[JimCR120]

There's an oldy we don't see much.

 

[philgabanski]

SU-34 On board camera, gives an idea of just what this thing is capable of!

Later that day, I cracked the fuselage during a very hard pull up from a high speed pass. Made one hell of a noise but the plane kept flying pretty darn good!



Hopefully more videos to come!

 

[Fluburtur]

Oh man I like you, I love those planes!
I hope you will release the plans for that MiG-31, I don't usually fly EDF but I will sure put two tiny edf units in this!

 

[RCman50]

Very nice work. I just read through the thread again, what kind of foam are you using? Just curious? I see your from Australia and didnt know if your using something like dtfb or something more like MPF (model plane foam) with no paper?

 

[philgabanski]

These are the foams I use. A combination of them. The Sukhoi planes are made out of 10mm Hobbyking foam, the rest I use depron I purchased several years ago. Hobby king do have 5mm foam as well, it may not be quite as good as depron but for the price I like it. I like using the 10mm for the wings as you can aerofoil it and have a relatively strong wing. The 10mm I bought was about $70 for 20 large sheets. 5mm are cheeper again, they also do smaller sizes.
The xps from bunnings is good for shaping fuselage parts and wire cutting or as I do sanding wings.
Next project below


Daiso also do foam but not as good quality or as cheep per sheet.

Oh and another su-34 video

 

[philgabanski]

The Mig 31 is prop slot, just hadn't cut it out yet as there is not much in the way of plans....yet.