KADET JUNIOR (future HEFA trainer)

[retiredVTT]

A few days ago we were given a plane that was built in the 80's but never flown. I thought it might make a suitable trainer when converted to electric power, so I passed it to Louie for removal of the engine and old radio gear. It appears to be a Sig Kadet Junior, three channel, with no ailerons.

I got it back today, minus all the nitro gear and large radio gear, and most of the grime that it had picked up sitting around for 30 odd years.

The first order of business was to cut a battery hatch in the front end, then install a battery tray, then come up with a suitable electric motor, and install it.

Since this afternoon we had a substantial rain fall, it was kind of nice to throw open the garage door and go to town on the Kadet Junior, while listening to the rain..!

The following pictures show the progress.


Bill

[retiredVTT]

The fuselage has plenty of depth to it at the front end so the ESC will be placed under the battery tray, still leaving lots of room for a 4S Lipo pack of up to 2650mah in size.

I came up with a Scorpion motor that should be ideal for this plane. It's capable of 1000 watts but should be perfect at the 600 watt level. The plane is not your typical lightweight electric model of today, but it also should survive some knocking about.

I'm thinking of propping for 37 amps at 16 volts for takeoff. Zoom zoom..! Hey, maybe it will take off at half throttle....that would be cool.

Motor is installed, and only required "standoffs" of 3/8" to get the prop clear of the front end.

A good day's effort..!

Bill

[retiredVTT]

..more progress,

..the original Kadet Junior had tricycle gear, with a steerable nose wheel. This one is now a tail dragger, with Carbon main gear, new foam wheels, and a non steerable tail-wheel.
..new control surface pushrods are in,
..ESC is in.

..servos are next, then balancing, and she's ready for her maiden flight, after thirty odd years of shelf life as a hangar queen..!

Bill

[yorcram]

Coming along nicely. Best part is that it will be able to handle more wind than a foamy trainer.
m

[retiredVTT]

Ready for the maiden flight on Friday night..

Bill

[retiredVTT]

..found these stats online, I'll weigh this one to see how close it is to the specs.

Bill

[retiredVTT]

The weight shown above in the nitro specs is 4.75 lbs or 76 ounces. The wing area is 2.98 sq. ft.

Now, with a 4S 1800 lipo pack it comes in at 50 ounces.

Wing loading should be 50/2.98 = 16.77852349 oz/sq ft which is a large improvement from 25.5033557 oz/sq.ft. with the nitro setup.

Should be interesting!

Bill

[Tom B T-28]

Nice Job Bill! Hope to get out to see the maiden!

[retiredVTT]

The maiden was interesting.....I learned that it's needs plenty of rudder to give you confidence that when you command it to turn...it actually turns! On my second flight which was brief I went with my high rate on rudder and things improved. However I lost the 3026 Scorpion motor (burnt out winding) so had to deadstick it.

Today I replaced it with a 3020-14 Scorpion which is a tad lighter which will help the balance. Still capable of 600 watts if needed. I put in some right thrust as well as down thrust this time (with washers behind the mount) as last night it tended to go left and climb.

Also, thanks to a reminder from Tom, I now have an exit hole, midway in the bottom, for ventilation. (I had forgot this step when converting to electric)

So ready for more experimentation on Sunday..!

Bill

[retiredVTT]

Now it flies much better, got the motor thrust angles set much better, opened up an "exit" hole for ventilation and dropped back to a 3S lipo pack and find it will cruise for nearly 10 minutes.

Now to put in an "orange" receiver and hook up the trainer cord and buddy box.

Bill