Quote "The original concept of the Ugly Stik was to design a radio controlled aircraft which could be built in an absolute minimum of time. Its purpose was towards a flying test bed for new proportional control ... which could be considered as expendable." Phil Kraft, the designer of what started as a plan in RCM magazine.

Another commentary:
This plane must be the most flown ever in RC. It comes in all sizes from two to ten feet in span. And all the variations that I have flown have been excellent. The original drawing by Phil Kraft does not seem to have been published. Perhaps he had no more than a few rigging lines and sketches when he started building. I expect he placed his radio control gear on the balsa sheets and installed bulkheads around them. The plans were drawn up for publication in Grid Leaks, I believe, and Jensen supplied kits. Dozens of variant drawings have appeared over the decades, not many of which improved on the original. Very shortly after the 60 inch span Ugly Stik came the 48 inch span Liddle Stik, and I still have the RC Modeler magazine from 1968 in which it was introduced. Graupner produced a kit for the 54 inch span Middle Stick which was beautifully prefabricated, and flew very well. I had one with an Enya 45, and can still remember the delight in finding that it grooved well in turns. It was my first aileron aircraft. I still fly a Stik, a version with 36 inch span, a 200 watt motor, and the exact same flying characteristics as the bigger versions. This design was right from the very start, and through Phil Krafts skill in aerobatics, nothing was overlooked. The cuteness and simplicity of the design allowed it to be taken up by many people who not have felt confident with the typical pattern model of the day. But this flew just as well, and still does.

My version is adapted from the plans in Spad to the Bone. I have (of course used Electric) modified only the Fuselage, leaving the Wings and Tailfeathers as per the original.

Having got some confidence in 2 mm Corro fuses after building & flying the Avispad, I used 2 mm for the fuse. Instead of ply reinforcement, I used 4 mm corro doublers, ply only being used for 2 formers under the wing, the Firewall, and the L/G platform. And yes, no yardsticks for the wing spar, 5 mm Corro doubled with a hefty Corro joiner brace. There is no Dihedral.

Specs:

48" span, 14" chord, 40" OAL, Turnigy 3542 1250 KV motor, 10*7 Prop, 3300 mAh Turnigy Lipo.

All-up weight is 1.8 Kg.

Wing top : 2 mm Corro
Spar : 2 X 5 mm Corro
Fuse : 2 mm Corro
Tail and Wing Bottom: 4 mm Corro
Formers and Landing Gear plate: 4 mm Ply
Firewall: 12 mm Ply

The wing is straightforward, STTB gives a very clear idea on it's build.

I wanted a Trike Gear set-up, having broken a lot of props on tail draggers recently but am unable to get a 4 mm nose wire   (any help here is appreciated )

So I used something I bought from HK in my very first purchase from them, last year, when I just got into electrics. It's actually meant for a low winger, probably a jet, but I used the nose gear only.

The "plug" is for the plug-in wings. One side will be plugged in, the other side bolted

Made a "nut sandwich" with 2 nylon nuts and some wood, for the bolts to go into

Wing bolt-down

Two major challenges: the CG was designed for a 40 size glow. Despite my using a 2 mm fuse against the original 4 mm, and reducing the fuse to 2 1/4" square against the original 2 3/4, was still tail heavy.

Second was the motor....would the Turnigy 3542 1250KV be enough?

Nice build Sanjay sir! The bolt on wing is nicely done. Always wanted to try one but never got inspired enough. Will try it in my next build.

Keeping all the calculations aside, and since you already have the power setup in place, if the plane is raring to take off from your hand at full throttle, then you are fine with the power setup

Thanks Vishal 

Actually I maidened it this morning, and all my fears about power were groundless: it flies at half throttle!

I did do some corrective action on the CG though

Video follows later in this post

The bolt-down wing does indeed make life easier - no more rubber bands 

You could also put a balsa block shaped to match the aerofoil in the wing, between the spar and the LE, drill and glue in dowels. But I used a 4 mm ply plate in front because the balsa was soft, and I had doubts whether it would hold the dowels under strain.

Fuse glued up.

Nose wheel bolted, main undercarriage bolted.

Hatch uses a standard corro hinge and a canopy lock.

Calvin's views on Balsa are on all my Spads    > >

To somewhat alleviate the CG issue, I changed the firewall and put on an extension motor mount

Decor with Sign Vinyl

Testing the motor: using a digital 'springless' spring balance & wattmeter

The moment of truth has come! Maiden time.

I am too nervous to maiden my own builds, plus Girish Sarwal is a far better flyer than I. So he is the official Test Pilot 

http://www.youtube.com/watch?list=UUQhf5Pkzb8t7lzTwN0AIYEw&feature=player_detailpage&v=JNwPKMweT9A

Many thanks to Maahin Beri fo taking the video

Need to reduce Aileron & Elevator throws. Otherwise she flies good - very sporty, as is supposed to be.

CG & Power were non-issues  

very nice build ! Sanjayji. 

Again another great build from sanjay sir...
And this looks really awesome...
I felt a bit tail heavy in that video? Is it?
But really a superb build with perfection... hats off...:

Sent from my Canvas using tapatalk 2

Thank you "bmblb"

Arun 

Re. tail heavy, it was a maiden, and the trims are being set.

On take-off, we gave high throttle - not sure how much is needed.

You may well be right, but we will only know after the next flying session. Could only manage one flight because of the rain

Sir,
Since she flew, the theory is irrelevant.
But this is what i was working on before i got sidetracked by visitors.
Minimum requirement
Wing loading about 16 oz/sqft
Stall speed sqrt of wing loading into 3.7, say 4x4 or 16 mph.
Cruise say 2.5 times stall say 40 mph or say 60 fps.
Or say 3600 fpm
Or 7200 rpm on a 6 in pitch prop.
On a 1250 kv this needs only 5 volts!

Another angle
Your motor is rated for max 45 amps, 665 watts, 1350 gms thrust.
Say 2 gms per watt.
For an 1800 gm plane you need say 900 gms thrust.
Or say 450 watts.
Or say 40 amps
Can your battery cope?

If you have checked power consumption and thrust, request you let me know,
As a test check on my estimates.
My guess was you need an 11 x 5.5
What did you use? 10 x6?

Regards to the only guy INTERESTED in really old stuff

Still another angle
Need say 75 watts per pound of Ugly Stick.
Or say 300 watts.
Only 25 amps!

Thats why she flies!!!

Iyer sir  

But, your second calculation destroys the first  

In fact, she flies at about 200 W! And my battery is 3300 mAh. ie 3.3 X 11 = 36 W-hr, or 2160 W-min

If I indulge in extra hot flying, I will get about 7 minutes flying, normal flying about 9~10 minutes

As I mentioned in the beginning, I'm using a 10*7 prop