J1 Trainer (Cub inspired)

Andre

Fly yes... land no.
Admin
My son is slowing moving into rc flying.

So it was time to put my knowledge to work and build a high wing trainer.

Meet the J1.

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Details:
2" at the widest (nose)
5" at the tallest point
36" from spinner to elevator end.

Will do. 50" wing (fits in the trunk).

1000 KVM D2830 Turnigy
35A HK ESC
10x6 Prop
Skis

Should fly well but won't know till the weekend.
I am closely following the Cub design but taking some creative twists.
Narrow, but double walled in sections, poster board on the section sections (top and bottom)
Used the FT Spitfire tail section but modified to have a full elevator.
Right now all the servos will be setup with slow #2 throws since it is a trainer.

Hoping this works out and I also get a nice winter plane as well ;)

A.
 

Flynn

Member
Nice work Andre! skis? That should be cool. Are you doing ailerons? Keep us posted with your progress
 

Andre

Fly yes... land no.
Admin
IMG_4273.JPG

I am going to do the coverings, min wax and test drive this puppy tonight.
 

Foam Addict

Squirrel member
Looks great!
It really has some nice lines, and it looks great on skis.
A word of caution though, from experience, those 2830 motors can only handle a 9x6 or 10x4 prop in the summer, but for the winter, that's a great prop you are using.
 

Andre

Fly yes... land no.
Admin
Just doing some test slides on the carpet this is going to be fun.

I run these motors with 10x7 on the twin/YC-14 all summer long with no issues.
Heck the two on the twin plane are flying with bent shafts. I thought about repairing them but for less them 10$ I simple bought new ones.

Minwax and then test drive outside on the snow.
I'll bring out the go pro and put some lights on the plane!
 

Andre

Fly yes... land no.
Admin
No flying tonight just "driving" around on skis to check the handling.

I will start building the wing later this evening.

Minwax is done.
 

Andre

Fly yes... land no.
Admin
HK Skis mounted on light weight posts.
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Piece of wood, velcro and rubberbands are used to secure it.
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Tail skid.
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Ready to do my test.
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Video is rendering… I'll post it once it is online.
 

Andre

Fly yes... land no.
Admin
Wing. Well half. Will do the other half on Friday.
I wanted a 50" span but that wouldn't fit in the trunk of the car so 48"x10 it is.

Based off the FT Spitifire wing but rounded edge, 24" long and 10" wide sections.
I used the FT Spitfire's wing because it is a great design.
The AJR-48 has crashed a few times (HARD!) and David's wing can take a beating.

Super impressed so I hope this works!

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NewZee

Member
looks great! I also wanted a "Cub" type trainer, and came up with this! need to copy your ski idea, its going to be a long winter!
cub 5(4).JPG cub 4 (2).JPG
please post a video of the maiden flight!
 

Andre

Fly yes... land no.
Admin
Oh that is great looking.

I am not sure if I will need to add the wing struts.

Those HK skis are nice but looks like they are on back order again.

Weather permitting we will try for a first flight.

Lots and lots of snow is expected.

I may have to build a 2nd one of these if it flies well enough. ;)
 

Andre

Fly yes... land no.
Admin
BTW what rates/servo arm holes are you using?

On the rudder and elevator I went with #2 (from the screw) since it is a trainer.
 

Andre

Fly yes... land no.
Admin
Had a decent evening.
Finished off the wing.

I can't test the plane for a while due to weather but I'm looking forward to it.

Sub 900g which is respectable.

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NewZee

Member
BTW what rates/servo arm holes are you using?

On the rudder and elevator I went with #2 (from the screw) since it is a trainer.

I'm using the 3rd hole out from the center screw, but I have the throws set low, and use a fair amount of "Expo" Since this is a trainer I purposely made my alerions small I wanted the plane to be very docile in the air, and it is!

I don't think I really needed the wing struts since this is not an aerobatic type plane, and I used the construction technique of the spitfire on the wings, I just did it for looks. They are a PITA and sometimes I fly without them.

Your plane looks great! good luck on the maiden flight!
 

Andre

Fly yes... land no.
Admin
Maiden was amazing. Checking the video now.
Have to paint the plane before the next flight. Very difficult to see a white bird on an overcast sky.

Super happy. May need to build a few of these for my Dad, friend and myself ;)

Video shortly.