Just wondered what people who have been flying it for awhile have done with their radios.....and what "mixes" they are using....

I've been flying the 16x4W APC on my YS91FZ, but I think there's a better prop out there. I'm going to get a 16x6 Bambula and reduce the diameter as needed to get around 9200 RPM static.

David

I'm running a program mix to get some up elevator with rudder in either direction. It seems that 10% is about right for low to medium rudder deflections, but at full throw the tuck overpowers the mix and it goes toward the belly strongly and rolls in the direction of rudder input.

My plane is fairly nose-heavy at the moment, I've just moved the tank back to the CG, and I'm moving the CG from 4.75" back to 6.25". I've been hearing that getting the CG back reduces the tuck issue. We'll see this weekend.

David

Pugsley,
I set up programmable mixes for elevator and aileron with Rudder as the Master for straight point rolls at full throttle. I run low pitch props so full throttle isn't all that fast, especially in knife edge flight. I use full throttle so I'm always near a constant speed so that the mix is always pretty close to perfect. If I knife edge at a lower speed, or knife edge loop, I just leave the mix on and fly the rest of the coupling out of it.

Marc,

Terrific job on the review!

David

I don't think any mix is necessary, except maybe flapperon and spoileron with up and down elevator. When doing knife edge, flipping to a real low rate elevator helps to calm it down. I usually don't, so when it tucks a bit, I have to be really sensitive with the elevator, or it is all ov the sky. Mine is a bit tail heavy/happy, she pitches up when inverted, so how do I mix that out ha ha.
DKjens

well after about 3 weeks of down time, i finally got my UCD in the air again yesterday. if everyone will remember, i was the first guy to have the horizontial stab/elevator break off in flight. my stab is now solid balsa with two spruce strips for spars, it won't break again!! and i needed some weight back there anyone to get my cg back some. i'm around 5.125 now with no cowl or wheel pants. will move the battery back some more when i put the cowl on and try it around 5.25 back.
as for the flights, i had one of our more experienced guys fly it for me (just in case) and with a little trim input it flew fine. he flew it 2 flights, loops were very light using only elevator input on medium and high rates with no snapping. ailerons were a little too low on low rates but great on medium and high rates. knife edge on low rate rudder was easy with little or no coupling. went to high rate rudder (only two rates on rudder) and it did a snap roll. i think i'm going to make low rate even lower and bring down high rate some too. i've got around 70 to 75 degrees deflection on rudder for high rates. landings were slower than my students trainers. actually i thought landings were a little hard, its a HUGE difference than my AW 90 size edge.
vertical with my 91fx was good, i'm running an apc 14x6 and the engine still has a long way to go to get broken in, so hopefully that will improve. if not, i will probably go with a ys 91fz or maybe the ys 110 will come out!!
will try much more this weekend, only got 4 flights last night before it got dark.
tony

With all the talk about Harrier Landings no one
has mentioned (I think) the inadequate tail
wheel that comes with this A.R.F. It is not the
right design and puts alot of stress on the rudder.
On mine I installed a Sig tail wheel same as
used on their Rascal with spring coupling to the
rudder. It is Sigs part number; SIGSH756. It
costs all of $16.99! It will require a ply plate
mounted on the bottom of the tail, but y'all
are looking for more tail weight anyway.

What do we know about an up comming YS 110 ??

Can I ask what is the idea engine for the UCD 3D? , for me it will be the most powerful yet lightest that can be possible to put the fuel tank close to the CG so which one would that be.

I was thing ing the YS 91 but someone said it could use a little more power?

I am going to get the UCD 3D as a 3rd to 4th plane.

Thanks, Dennis

Tailwheel,
I believe I mentioned it at some point. I hate tailwheels which has a direct connection and possibility of transfer of force to rudder. I like the Klett tailwheels, but have been told they are not made any more, so I have a Du-Bro on mine.

Engine,
I just went from a YS120NC to a YS120SC, which has made the plane balistic. My uplines from hover is faster than some planes' down lines ha ha, and my tail is still attached. YS120 is what I say for power, or an OS160FX would be fun as well.
DKjens

I just flew my UCD3D today (3 flights) and it flew great! I have an OS 91 pumper in it with a 14x6 prop. (will try a 15x5 once broken in a little more) This is what they (GP) recommmends so I went with it. It balances out excellent,... about 5" (4.75-5 recommended). Even with this new 91 pumper (ran three tanks through for break-in), it has PLENTY of verticle power. If you want to send it to the moon, use something bigger. Hovers excellent with plenty of pull-out power. I flew this plane mostly at 1/3 throttle and it is a ball! It is not a fast plane by any means (as designed). Nice slow landings too... Plenty of reaction time, even more than my Falcon 56 trainer! Can't wait to fly it again as I still need to iron out a few coupling issues (mainly with KE,... it tend to pull to belly of plane). The fuel tank is installed as per the instructions. I might move it above CG to see what that does.

A VERY FUN plane nevertheless !

I personally cannot recommed the YS line of motors...

They are indeed powerful for their "size" but can be VERY finicky in srtting up and running. They PREFER according to YS Performance 20/20 blend fuel. We have seen them to be even finicky about brand of fuel.

I have 3 (2 91's and a 120) and I'll NEVER buy another... EVER.

I had on eon the nose of my U3D and it had plenty of power... next day? The momo decided not to run at all... FOR NO REASON!

I went out and bought my first Saito... the 100.... Absolutely the BEST engine for this plane... GOBS of power, lightweight, runs perfect (and it's not even broke in yet).

I can't imagine ANYONE putting an O.S. 160fx or a YS 120 in this plane... WHY would you want to burn that much extra fuel when unlimited vertical is available in a smaller package (and less money)


Again... in my experience, the Saito 100 is an "overpowering power plant" for this plane without "feeling" like it's too much motor....

Why do they have 3 to 1 or better thrust to weight ratio on the 40-50% aerobatic planes, that would seem like a lot of unnecessary extra power - NOT. You fly the plane on a very small throttle setting, but you often 3D it on as much as you have available, and for some maneuvers, you need alot to do it well. I know a YS91 will hover this plane, but will it put enough air over the elevator to bring it around fast enough in a waterfall for my taste? NO. I bet my plane, with the YS120SC, and tail weight will fly as slow as somebody elses with an OS91 4-stoker or 2-stroker. Yes, I do advocate that every ounce saved on a 3D plane makes it a better 3D plane, but in this case, the load per area is so small, even with a YS120/140, that it'll still "float", or have a light feeling.
DKjens

I agree. I mainly fly funfly. Where they weight about 3.5-4.25lbs. and put a .45 w/ a moose can on them. With that much power it will easily hover a 5.5lb plane.

As w/ a fun fly and other hovering airplanes, you don't want to pull out of a hover, you want the ability if you need to to shoot out of a hover. Why else would DA-150, 3W 150, that put out approx 85lbs of torgue on a 35lb plane. I have talked to and ready about 35-40% airplanes hover around 1/4 throttle. My UCD hover over 1/2 throttle. The next Gaint scale you see hovering. Listen to the motor in a hover, it sounds like its at a high idle. then listen to it doing a knife edge loop, it sounds like it working 3 times as hard. In my opinion to 3d you need all the power a plane can handle. I have heard that if you fly a 40% aerobatic plane w/ a DA150 or 3W150 at full throttle on a horizontal straight line you will rip the wings off. And I do believe a UCD can handle more power than a 91 has to offer. You just have to know when to use the power.

I have experimented w/ my UCD w/ Saito 91. With a lot of props. I have figured out that it hovers better w/ a 15x4w, ( I am sure a 16x4W hovers even better) but it pulls out better w/ a 14x4w. I am going to keep playing w/ more nitro and see it it helps. since I already own a Saito 91, I am not going to spend the $270 on a Saito 100 or YS91. Because even the YS91 owners are still wanting just a little more power. I will probably swap over to a ST90 w/ moosecan. That combo w/ swing a 15x4W prop about 1000 more RPM than a Saito91.

I fly mine with a Saito 100....it pulls out of a hover fine.....does it jet out? No. Does it pull out like a 35 % Edge with a DA 100??? Yes. I believe power to spare is awesome....but so is a light plane....A OS 1.60 on this plane would just be silly. It is not worth the weight that it would add......but like I said. To each his own.

This plane is awesome with the Saito 100. It flies, to me, like a 35 % Edge......low wing loading, all around great flying plane.

Yes, it does have SERIOUS roll issue with the massive rudder. I'm not use to a rudder this powerful....I'll figure it out though.....

Pug

My plane waterfalls with the YS91FZ. It may not rocket out of a hover but will pull verticle.

My ST 90 powered UCD is nearly ready to fly. I would really like to put a mousse can pipe on the ST 90, but I don't know what size can to use. Has anybody done any testing to see what size can, and what and size stinger tube works best?

If someone else has already done this, there's no sense reinventing the wheel.

If i were to go with the saito 100 would I not need a Pump to put the fuel tank over CG?

What pump would you reccomend and where can I get one?

What details would you give about using a pump?

Do you think the Saito is more powerful than the YS 91?

Thanks Dennis

I have the Saito 100 on my UCD. It turns 15x6 @ 9,500. I was informed that YS 91 can do over 10,000 with the same prop. If you are concerned about putting the fuel tank at the CG, then get the YS. Just be ready to put your battery pack under the stab before glueing it in place.

Dave,
I have talked to a guy w/ a 91FX w/ moosecan on his UCD. His flight performance was unbelievable. I think he said he is turning a 14x6 at almost 11,000. He said his pipe was around 7 1/2" centerline. And it looks like he is using a 6oz. moosecan w/ 1/4" Diameter stinger.

Also Dave, I am fixing to start building me a moosecan for my 40fp. I have read in other post that you love your 40fp w/ moosecan. Can you tell me what your pipe length and can size is. For my ST45 I have it at 4 3/4" and 6oz can. Since the 40FP is a smaller motor, I didn't know if I need to look for smaller can, or run a shorter pipe.

Thanks,

How do you get the long moose can to work when the exhaust is inline with the wing

RHD,
w/ the UCD the motor is inverted thus on normal motor putting the exhaust on the left side of fuselage, that is if your standing behind it.

If your using a rear exhaust motor, then the UCD has a channel the the front part of fuselage for tuned pipes. My brother has a YS61 and tuned pipe on his. The only thing is that he has to detach the tuned pipe when he takes the wing off. But its not problem.

I saw pictures of the bottom part of fuselage somewhere here on RCU. and that shows the channel in fuselage.

Simply rotate the engine mount so the MCP clears the wing.

Here's a photo of a MCP on a Q500 with the engine rotated so the MCP is directly underneath the plane. This is what I have in mind on my UCD, but I don't have the ST 90 header yet.

Thanks guys,
I saw the channel, it is like on the Balsa Nova. I was too lazy to rotate the engine since the had all the holes drilled and blind nuts inserted. You would have to rotate it to put the pipe or a moose can on.

Dave,

You'd need a long exhaust extension between the engine and the header, to clear the bottom of the fuse. The engine centerline is quite high on the fire wall.
DKjens