Hey guys, do you think a Great Planes 40 could hover with a 91 Surpass on the nose? What power to weight details do you use to determine a good 3D .40 size plane.... I have an extra 91 and the Ultimate kit in the basement. Would this be a good match for learning alittle about 3D?

yea it will hover. 4 pounds and under a satio 72 .5 pounds and over 91 or 100 satio. 7 pounds satio 180. 9 or over a little os 160 fx. power is ghoood

Do you see any problems with the 91Surpass on the 40? I need to figure out the weight with the 91 on it. Is there a good way to learn how to get a plane into a hover? How would you oversize the elevators? Anything a novice is going to overlook in building? Thanks.

If im not mistaken, The OS 91 weighs several ounces more than the Saito 91. If you already have the engine go for it. You shouldnt run into too many problems. If not go for the Saito 91 or 100. Both are light with a great deal of power. Hey prophanger, what plane are you flying with a Saito 72 that weigs less than 4 pounds. My edge weighed over 4 pounds more than the heaviest plane you recommend for the Saito 180 and I had plenty of power. Any more would have been a waste. Anytime you are worried about overspeeding the plane in a vertical line at half throttle, I think maybe you have too much power.

Thanks for the encouragement; I already have the OS 91 so I will try that setup.... can I go stock dimensions on the elevator or should I upsize? Once at the field, is there a method to get into a hover that a beginner could try (with alot of altitude).....

i have seen one fly with the os 91 on it. it was fine. he had to use a higher pitch prop to clear not much room. i think a 13/8 .the cg was fine battery under back of lower wing.

ok well yea i like to much power. i fly helicopters to and you get used to blasting out of hover's. so i have to make my planes keep up on pullouts. so yea a os 160fx is a little much on a 60 size u can do . but its fun to watch.[sm=bananahead.gif]

I think I will get taller aluminum gear to clear the larger props..... still can't get an answer about the elevator size; do I need to enlarge them or just build them stock? Anybody know?

yes add some to the elevator and rudder

i have Ultimate 40 and i used .60 , i think its unnesesary put more elevator and ruder. dont put more. only take back the cg.
i take the bateries and put more back i can. if i flying and put the engine in ralenty, its get down slowly, slowly but not stall.
the Ultimate is short and don´t need more elevator and ruder

Sergio

If you do decide to enlarge the control surface, dont just make it bigger. All you need to do is move the hinge line forward where you have less stabilizer and more control surface. Hey prophanger, I didnt think about it that way. Heli blast out of hovers. I bet a 160 in a Ucando is fun to watch.

How much forward would you move it? I looked over the plans and I would guess about 3/4 inch forward would look right..... I am kind of winging it; I will strengthen the horizontal stab trailing edge with spruce instead of balsa; especially if making it smaller. I don't think the rudder needs to be any further forward. Thanks for the input.

It just depends on how big of a surface you want. Usually I would think that 2/3 of the surface be a control surface. Also it the elevators dont have counter balances you might look into adding those.

What do you mean by "counter balancers"? I will make the forward outer balance areas (that goes forward to the front of the horiz stab) on both elevators; is that what you mean?

I don't know why i don´t load my images of ultimate, but I insist don´t do anything . Put your engine and fly,
Put the elevator in 45Âş and fly (with the batteries back) and tell me if you need more elevator.
Do a hammerhead and put all the ruder and look the Ultimate go anyway, you don´t need more ruder.
Do Snap and stop in level with all the controls full, Fly and feel the airplane and later if you see you need more , ok put more.


Sergio

I tend to agree with ****cano; my sig one is hinged at the center of stab, and 45 degree throw is plenty of elevator. definately keep it as light as possible. it will harrier better that way. as weight increases, so will wing rocking. mine is pretty good, will rock slowly when harriering below 45 degree nose up. one thing to watch for, though; if you go a little over 90 degrees while stationary or backing down, it will torque roll so keep that in mind! mine is saito 72, 4.75 lbs. does well. hope this helps!

more pictures
I can´t load images sorry