Update: latest video

SU 37 another flight (1 min 58 sec)

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Hi there,

Sharing my latest project: a prop-in-slot conversion of the great SU-37 Flanker by Steve Shumate.
For details (plans, construction guides, etc), please refer to the original thread: https://www.rcgroups.com/forums/show...anker-Park-Jet

I will use this build log to document my conversion only, and hopefully arrive to a great flying jet

Here are the specs:
- Wingspan 760mm (as per original plans 100% size)
- AUW: estimated in about 1kg
- Motor: Turnigy Propdrive 3530 1400kv
- Propeller: 8x4.5-8x6
- Battery: 4S 2200mAh

Material: styrofoam boards cut at 12mm thick.

I'm also planning to put my 3D printer to good use and printout a few nice and scale details.

The power train should pull between 1.9-2.4kg and make the jet fly at about 150km/h (according to ecalc), which should make it for a nice fast and furious little jet. I also expect it to be quite noisy with the prop-in-slot mod.

Wish me luck!

Here are some photos to start with...

This is how I reinforced the nacelles for the prop-in-slot configuration.
Also reinforced the nose with carbon fibre.

And here is how the nose looks like after gluing and sanding

Here's how she looks with all the parts sanded and presented in place.
Looking good!

Testing all the parts and electronics in place.
I did this to make sure she will balance ok with the battery in the back/mid nose.
In any case, I will leave cutting the prop slot as the last thing after painting and scale details so I can place the motor in the right position for balance.

Paint job is done. Next step will be panel lines and decals.

Panel lines and decals complete.
Time for electronics and remaining plastic parts.

Wow, it looks way too nice to cut a big slot in it!

Beautiful work!!

... and here is how she looks like now.
OMG, the noise she makes!!!

Your slot is too narrow -- it needs to be extended towards the nose of the plane to help reduce the noise.

https://www.rcgroups.com/forums/show...sign-and-Tests

Thanks for the link. Will definitely look into it.
I did some tests yesterday and I had to put my ear plugs in as the noise inside my garage was unbearable...
(it's my first prop-in-slot plane as you can probably tell)

Prop in slot designs are typically VERY noisy.

Personally, I think you would have been better off to leave the motor(s) at the rear of the plane -aka- pusher instead of prop-in-slot.

I tend to agree with you, Sammy.

This is my first prop jet (all the others I built were EDF) and I thought the prop at the rear would be more of a pain for take offs and landings.
I'll go with this plan for now:
- Follow the guidelines in the link to see if that makes the noise more bearable
- If not, I'll move the motor to the rear and re-glue the cut out parts in the slot (I think I saved them just in case)

I definitely want to keep this one as a prop jet as I'm sick of EDFs with their low thrust and high battery consumption. I wanted this jet to be a rocket and based on the bench tests she will be! (the powertrain delivered nearly 800W on the bench)

Good plan.

Good luck!

I went through the thread and cut a bowtie slot on my SU-37.
The result was.... disappointing
The new slot looks uglier (much bigger) and the noise is just the same but with a higher pitch.
I'll maiden her like this but I reckon I'll just glue the parts back and keep the smaller slot...