I decided to use 4-40 hdwe because of the size of the control surfaces, I didn't want them bending under load. The tank, wheels, and control horns work ok. I may try to mount a servo under the bottom and use pull-pull on the rudder (that thing is HUGE). Don't know if there's any weight diff between YS and OS, but I prefer the YS because it is stronger, and the pressurized fuel system would help with fuel delivery in nose high maneuvers like this plane will see a lot of. I also plan to use a tailwheel mount that attatches to the fuse instead of putting it between the rudder and fuse, they seem to not pull out when dragging the rudder like the one that comes with the kit.

The OS weighs about 23 oz ready to fly. The YS almost 27 oz, so there's about a 4 oz difference. The OS only has acceptable power for a 91 sized 4C, while the YS is the king of this size, being compared to some 120 4C rather than 91s.

How did everyone's planes balance? Was it tail heavy due to all those servos being located in the back of the plane (aka would a heavier motor actually balance the plane better)?

Thanks!

HEY GUYS
ALL THIS TALK ABOUT THIS AIRPLANE MADE ME GO BUY ONE!
I ALSO BOUGHT A SAITO 100 FOR IT AND I AM PLANNING ON RUNNING A 16X4 WIDE BLADE APC. DO YOU GUYS THINK THIS WILL BE PLENTY OF POWER? I WAS GOING TO GET AN OS 91 FX AND INSTEAD BOUGHT THE SAITO 100 BECAUSE IT WAS LIGHTER AND I THOUGHT I WOULD GET BETTER PERFORMANCE BY SWINGING A BIGGER PROP. ANY INFO WOULD BE HELFUL.
THANKS

After watching one fly this weekend with an OS91 4 cycle, I believe the Saito 100 will work well. The OS engine flew the plane great. It was definitely not underpowered.

But, FWIW, we are basically at sea level here (141 feet). I don't know what affect high altitude flying will do to the motor.

EXTRALONG,

i hope you get this thing done so I can see you Hoover it with Sean

Andrew

Come on guys

How about someone give a more complete report than "yes it will hover---no it wont hover".

No offenece, but some of us would like to know about things such as knife edge, flat spinns, elevators, harriers and the like.

Dave

Didn't get much of a chance to fly it due to the fact it didn't belong to me.

But.......

OS91 4 cycle. 7 lbs 10 oz Motor brand new and not broken in good yet.

Knife Edge: Pulled toward the belly. Definitely needs coupling
Waterfalls: Great! Wants to gain altitude in a Waterfall.
Knife Edge Loop: Yes it will. No Problems other than needs coupling.
Hover: Yes it will. And it has enough power to pull out well. Not blistering fast. But solid.

I did not try any flat spins or blenders due to it was not my airplane and the motor was brand new.

I just received my U can DO last night. Total components weight after unpacking was 4.71 lb.

This means that 7 - 7.5 lb is achievable, but not with the recommended equipment. 7.5 - 8 lb is what you'd get if you used standard size servos and a 600 mAh NiCD.

I've seen Sensai's plane fly with 8411's (heavy), an OS 91FX (heavy), and a 1500 mAH pack (heavy -- or was it a powerflight pack). He claims 7.8 lb. I'm curious whether his airframe components were lighter than mine...

I've found the following issues/problems so far :

1) The outboard ends of the aileron LE's were oversanded, causing a 3/16" assembly gap outboard of the last hinge.

2) Fuelproofing -- the firewall is fuelproofed on the outside, but there's no fuelproofing in the fuel compartment in the fuse.

3) The fuse former just behind the canopy was pulled away from the fuse side with glue in the slot. It looked like the fuse wasn't kept in the jig long enough for the glue to cure.



Overall comments :

o This ARF requires less user assembly than any other I've seen. You don't even have to join the wing halves!

o This thing is built strong. The average person won't have any problems with it.

o The monocote was applied over itself -- e.g. the wing bottom is entirely red with white squares monocoted on top. This will lead to bubbles eventually and makes the plane several ounces heaver than it otherwise would have been.

o This plane could be constructed at least a pound lighter than it is now. I'd love to pay extra for one of these that came in at 6.5 lb with a saito 100 and mini servos!

HOW HAS THE PLANE PERFORMED WITH THIS ENGINE? CAN YOU TRUELY GET GREAT EXCELLERATION OUT OF HOVER?

I have a UCD w/a 91 fx and I am not disapointed. It will definetly pull out of hover no problem. It won't rocket out of hover but It will pull out with athority. I've been having fun doing a tail slide in hover, then pulling up a little and do another tail slide. Put a tuned pipe on that 91 FX and I bet it would rocket out of hover.

I have a YS120NC that'll go in my U-Can-Do. Does the firewall come with right thrust, if so, how much? How much right thrust do You put in your engine, and do you add any down thrust?
I smacked my Extase/YS91AC into the runway weekend before last, waterfalls at 10' + a little slow pulling out right side up = pancaked in on runway and needs a bit of repairs.
DKjens

DKJens,

The only one I have seen did not have right thrust in the firewall. Right Thrust was added by using a few washers.

I hope this helps.

Anybody have problems with the inverted engine? Do you prime by plugging the muffler or....? How do the .91FX's run inverted? Thanks for any replies


Rein

Here's how I'm doing pull-pull rudder on my UCD. Just cut opening right in front of last former, glue a piece of lite ply to screw to, straight shot to the control horns.

Which engine does anybody think would be better at around 3000 ft of altitude,

a satio 100 or os 91. I want a engine that allows for max 3d performance

I can not make up my mind between the two

I DO NOT LIKE THE TAIL WHEEL ASSEMBLY. NEED SOMETHING LIGHTR TO ATTACH TO BOTTOM OF FUSE. THE SULLIVAN SYSTEMS ARE GOOD BUT HEAVY BY COMPARISON TO WHAT IS THERE? ANY SUGGESTIONS?

Hey Rob, you are lucky you beat me to Glens or I would have had that bird! Looks good. Now you have to try Jim's trick....lose ALL the tail surfaces and keep on flying and land!! I think I'll try an old ST 90 in mine.

os 91 four stroke!
WOO Hoo!

hey rick, please give us your flight evaluation. Still workiong on mine and waiting for my Satio 100 to come in.

Well, Great plane!
Very stable in hover/ TR
Os 91 has just enough power! saito 100 would 1 st choice if I had one! all thought I would not go out and buy a saito just for this plane!
Rudder is very powerful and will cause a wing to dip if to much is used.
I would also like to try some right thrust in mine I don't know why there wasn't any built in!!!
I ran a y on the elev and ran one servo arm up and the other down with no differential (Amazed me!) at all. Hitec 605's

YNOT,

Please tell me more about your OS 108 being too wide for the fuse. It's suppose to be only 6 mm wider than the .91. I was thinking about using a 108, but was told it would have too much torque. Hate to hear that it won't even fit.

OK guys...what do you think.. Best engine for this plane?

YS 91...Saito 100...OS 91FX??

Chris, about your avitar, I take it you LOVE Fords, Dodges, and Chevies??

Ok, flew mine today. 7 flights. It seems to lack pull-out power from a hover using a Saito .91. I'm using a 15x6 prop and that could be the problem. I ordered a 16x4W and we will see.

The BAD:
Flat spin sucks. Waterfall sucks, the plane does not stall and I have 45 degrees on the elevators. Harriers rocks the wing like crazy even with spoilerons. Inverted harriers are rock solid, maybe because the fuse is lower than the wing when it's inverted? don't know! 2-56 push rods sucks, it bent doing a blender, switching to 4-40 with carbon fiber. No built-in right thrust, had to add three washers to get 3 degrees of RT and now flies perfectly straight up.

The good:
The best thing about it is the freaking Knife Edge. The plane does high alpha knife edge with only 30% rudder input on high rates and does knife edge loops on full rudder on high rates.
But the very best thing this plane can do that I have never seen done on any plane to my knowledge is KNIFE EDGE WALL, that's right!!! KNIFE EDGE WALL. I switch to 3D rates and half throttle, bank the plane 80 degrees and BAMMM Jam the rudder to full and the plane just go verticle, this bends the hell out of those 2-56 push rods so becareful. Also the plane flies with just 3 clicks of throttle maybe just under 10mph. Lands slower than any trainers I've seen.

My current CG is 5-1/8", it feels nose heavy to me. I'm making it 6" and maybe the 3D problem mentioned above will perform better. We will see.

WILL HAVE 3D VIDEOS SOON!

Checkout 3d Gallery @

www.uaerc.com