Are all you folks inverting your YS 91?
How much cowl are you removing to keep it cool?
I thought of turning mine out the side to help the cooling.
I just wonder if this will be enough engine at 5000 ft.?
I also have a Webra 120 to put in it if the YS won't work.

My question a few posts back regarding the 9C and the ailevators probably wasn't clear..I have it setup so I'm not hitting my mechanical limits as it is now when in ailevator mode but question is whether or not you can get maximum elevator throw at the same time ailevators are activated...I can get full throw out of either one but that is with the stick in one corner but just pulling back on elevator only gives just a portion of the total available throw...this of course makes the ailevators "proportional" I guess. In other words with ailevators activated can you have the full amount of throw with just full up elevator as it seems the remainder of the throw is reserved to allow for ailevator action. Hope this question makes more sense.

I'm at a CG of about 5.25" with an OS 91Surpass and my question is, are you guys getting pretty bad pitch and roll coupling with your UCDs? Is this a product of my CG? I have it programmed out for knife edge flight, but with extreme input for a knife edge loop, it gets pretty hard to make it look respectable.

Also, on knife edge spin, it'll do a slow spin, it really won't tighten up, is this a CG issue as well. I've got an 1800mah pack and receiver all the way to the back of the radio bay, I'm already marginally powered for knife edge loops, how are you guys getting your CG back without adding weight?

Also, I'm using a 15x4W and I've tried a 14*6, do you guys see any other options? It'll pull out of hover and all, I'm just looking for free power, overall I'm very pleased with this motor though, very consistent and user friendly. Thanks,
Eric

I have a YS 91 inverted in my UCD. No problems starting or running. I spin 15X6 APC well over 10,000. I put the engine 1/8" back from where they tell you because I knew I wanted to be tail heavy. I also mounted the tank over the CG. The YS91 is more than enough power. Even with several ounces of lead in the tail I hover with less than 1/2 throttle. If you use an inferior brand of 4 cycle, you will probably have to go bigger.... :devious:

Yes, the UCD has TONS of rudder coupling. It just takes some time with the radio to mix it out. I actually leave it on all the time, as it makes blenders and flat rudder turns better/easier too. Now knife edge loops are pretty easy.

Rick

I found a use for the stickers no one will put on their planes. Two of my students at the field today gave me a beautiful gift - a metal case for my transmitter. Better than on the plane....

Rick

I have a YS 91 on mine and it has plenty of power.
So Far I have not had any problems with the engine being mounted inverted. Starts easy and runs well. Prop 15X6 APC, 30% Cool power heli fuel. Mine hovers at a little over half throttle. I do not know where the C.G. is. I just kept adding tail weight unitl the plane would hover easy and waterfall.

Flooding: I have the OS 91 surpass 2 inverted, and yes I have to start the motor soon after fueling or the carb will flood. Priming is not needed to say the least.
What recevier batteries are you all using? I use a volt watch and my battery is a 4 cell nicad 1500 scr pack. I notice that after a single flight that I have full power available if 1 servo is used but hit a combo as say a snap spin and it goes down to almost to the unsafe level. Means I will only fly 2 flights per charge even though it shows full power with 1 servo being used.
I just picked up a 2000 mah nmh 5 cell pack thinking it might give added power to servos without drawing too much.
Not up too much on this, been flying since april and this is my acrobatic trainer. 7 flights so far using the medium settings, 3d is awhile off yet.

HEY GUYS! I am going to get one of these. ???
Would you go with the YS91 fz or the Saito 100. Which has more power? Please help so that I can start figuring out the setup and which engine to order.

I flew mine today, only got about 4 or 5 minutes in before my engine died{ anyone want to buy a YS 91 cheap } lol. When it was flying it was a very fun plane to fly. Think I'll scrap the YS & get a Saito. It'll allow me to move my CG further back without adding weight.

To add tail weight what about filling those 2 holes where the stab bolts are with some lead shot? Seems like an easy place to get an ounce or more way in the back.

By setting your ATV on both the Aileron and Elevator throws to 140%, and using 100% Elevator Dual Rates, pulling or pushing the stick for elevator only will let both elevator halves travel to the maximum deflection allowed by the transmitter.

Then if you start to move the stick sideways for ailevator mixing while maintaining full up or down elevator stick, you will see one elevator half start to travel back towards neutral, and the other elevator half will remain stationary since it was already at the maximum travel allowed by the transmitter.

Or am I still misunderstanding your question?

Archer: It sounds like you might have a bad cell in your battery pack. I'm no expert but the most decieving thing in batteries is how to tell whether you have a bad cell or not. Batteries act differently loaded and unloaded. Head over to the Radio section and ask a few questions.

Cured my flooding problem. I'm now running my TT FS 91 sidesways instead of inverted. I'd hate to cut the cowl up for this so I won't, I'll just fly it with out it for now and see how it flies.

I'm getting about 8 11 minute flights on my 1650mAh 5 cell pack. This is with all digital servos. A 4 cell pack would last even longer. I'd also guess that you have a shorted cell in the pack.

I've got about 30 flights on mine now and it's holding up great. It even survived a deadstick from a hover at 10' AGL (barely).

I have about 3 degrees right thrust and the plane still turns right hard during harriers and when jamming on the throttle, so I've added another washer's worth of right for the next flight.

Has anyone flown this plane with an OS Surpass 91 II (with pump)? The instructions claim it is the perfect match. Just curious about performance.

I'll be flying mine this week with the OS Surpass 91 II (minus pump)...would think basically the same deal outside of the pump fixing any fuel draw issues. Will post some early flight reports as they occur...this plane will be reviewed (if I hit my deadline) in the next issue of the RCU Magazine here at the site.

Stevezero,
you ask the question how long is the flight on a saito100 or Ys91.
I have a Saito91 on mine and so far i am up to 12 minutes. At the end of the day when i drained my fuel tank, I think I still had a few ounces left after a 12 minute flight.

WHAT MIXING SSET UPS ARE YOU HAVING TO USE ON KNIFE EDGE?

Archer, I'm also using the SurpassII w/o pump but I'm not having any flooding issues with fueling it and standing around for a few minutes. My first flight of the day I have to actually prime the motor. Are you fueling it up with the Carb at wide open maybe? Just taking a shot in the dark, I don't know why it would be happening as the fuel tank location is pretty much locked in with this plane, so that can't be the difference. You glued the tank support in behind it with the tank flush with the firewall and level right? That's a stumper, sorry I couldn't be of more help.

eness76 : What kind of performance does the Surpass 91 give you? Does it pull out of a hover good ? What prop are you using? I'm thinking of buying one to replace my YS 91, thanks for the help, Rob

Well, mine has 2 tanks of breakin on the ground, and 9 flights so far, and I'm running a 15x4 prop and getting about 9650rpm peak. It'll pull it out of a hover pretty slowly and steadily, but it's not a rocket. It'll just barely get it around on a knife edge loop. It's well documented the the YS makes a good bit more power.

Two of my friends did their first flights last Thursday and Saturday.
Both called me to tell me how much they loved the airplanes. They are having their grins surgically removed from their faces. I flew one of them last Sunday. This airplane is very light, extremely agile, and very docile when you want it to be. No matter what it's doing, let go of the sticks and it stops doing it. We almost hovered it in a 20-25 mph wind. It can do whatever you can do and more. They both started hovering on the first flight.

If you're looking to practice 3-D, this is the airplane to learn on. It's built light so it's not going to take much banging into the ground or bad landings, but it Lands like a breeze so there shouldn't be many hard landings anyway.

Both airplanes are powered by 91 sized four strokes and have more than enough power. Most flying is less than half throttle.

I ordered mine yesterday!

Keep 'em flyin'

3 items:
1) The new 5 cell nmh pack works fine so looks like a bad cell was the issue. Thanks all.
2) flooding: I mounted tank standard as instructions. I fule the plane with the tubing disconnected from the carb. (I will be adding a fueler with the cowl at later date. No big deal but I have to watch for lockups when starting. I posted since the reviewer had asked the question and was not getting answers.
3) performance of 91 surpass 2. 9 flights now. I am now at the stage were the plane will pull slowly out of a hover but I am still running rich. 15x6 prop. CAP232 of this list flys the same plane on the 91 sup 2 and his is fully broke in. It pulls out of a hover with autority. seems unlimited vertical. It is not an extreemly fast pullout, but is with great percision.

Looks like I too will need both down and right trust. I have to use down elevator and alot of right rudder to hold a hover or extended vertical line.

The right thrust should be 2 degrees according to GP. Mine had none built into the firewall so I had to add 2 washers to the back of the left side of the motor mount and slide the mount itself to the left as the marked line was actually center rather than off to the left where it would need to be so the prop would be centered after adding the 2 degrees...the wing, elevator and downthrust specs are 0/0/0 according to GP btw...

What's the deal here? GP forgot to add right thrust during manufacturing?