You may want to also try a 12x5 prop. On my .46 TH equipped 40S, the 11x6 makes this a VERY fast airplane, almost too fast for a biplane. Several people have suggested that I lower the pitch to bring it's speed down a bit.
If my Pitts muffler comes in this week then I give that a try. I'm not looking for ultimate 3D or a rocket ship...lol I just wanted to be different and have a enjoyable experience while flying.
I'm not saying anything to make anyone upset BUT, I can only stand so many of the same planes at flying fields at one time.. lol

You guys seem to know your bibes. any thought on the nitomodels pitts

You sure have that right!

The 11x6 makes this a little rocket.

After seeing me fly my plane one guy walked up to me and said the same thing... bigger prop, lower pitch, and told me to use a 13x4 if possible.

That one has been calling to me too.

It's not fully sheeted (which I would prefer all other things being equal.) but that may mean that it too would be a good electrification candidate.

For the price you could not go wrong with the Nitro Pitts. I was thinking of getting it for a backup to my P-51 PTS if it has a bad day . Just put a Evolution .61NT on my P-51. Hope to try it out this weekend.

opjose, I have a couple of questions about the ultimate 40. First, what is the surface movement of you ailerons? Mine is at 1/4" each up and down. Is this enough? I am looking for some nice, not outragous, concecutive rolls that don't lag. Also how for off is the CG compared to the directions 3.2 inches back from top leading edge? I hope to maiden tomorrow 11 09 if the wind co-ops with us.

one of my flying buddies bought one their delta flying wings. the instruction manuel is about worthless. i looked at the model very carefully and to be honest i was not impressed with it at all. he had it about half assembled and because the manuel was so bad he was having problems putting it together.

Russell I couldn't agree more the directions, well, for lack of a better word, suck... Point blank. However The World Models had the Bipe set pdf and all I done was print them and at least I could read them. But it wasn't rocket science to put together. I was all covered, rather nice I shall say, and easy to figure what went where.
Hope he gets it flying and has a good time and forgets the bad step to get in the air...

The instructions call for rather low throws for the aileron servos.

I've been able to increase the throws to just shy of 3/4"... however to do so I had to shave away a little material around the wing mount bolt hole. Just enough to let the lever rods move a bit more.

I also used a longer servo arm than what is normally used with the mini servos.

I then set the aileron servos to 130% travel.

This makes the plane VERY responsive when it is travelling at a good speed, on rolls. SNAPS are almost invisible....

Check out the WM plane video for the glow version and you'll see how fast the plane is on snap rolls... It's FAAAST.


I usually fly it at low rates (60% of this for the ailerons) and flip to full rates when doing things like fast snaps, etc.

You don't want to usually fly at the higher aileron rate, as if you have this on (and high rates on the tail) during takeoff you may stall the plane.

I did this one day, pulled back too fast and early with high rates on, and had enough height by then to recover... it does fly slow enough... but high rates on the ailerons and elevator are not a good idea at takeoff.

For your LOW rates be within the recommended HIGH rates, if you are an experienced flyer.

Otherwise if you are anywhere close to the recommended you'll be fine...

1/4" sounds about right, but use the radio to dial in just a little more.


Make sure that the plane tracks straight before you fly. Test it several times.

It will yaw left on you during run up, and roll left on you when the wheels come off the tarmac.

The left roll is fairly docile, the left yaw can throw you into a ground loop if you are not ready for it.


As far as the C.G.

I originally set it to spec, but have since upgraded the wheels making it a bit heavier in the nose.

I've had no problems though I'll bet the C.G. is now well forward of what is recommended.

I'm hoping the Ultralites will bring the C.G. back to spec.

If I recall I have an 1800mAh battery pack sitting under where I put in a pilot... or off to the side (I have several of these now, so that is why I'm a bit vague...)... I crashed one...

The last one I put together has the T.H. .46 engine mounted inverted with the STOCK(!) muffler hanging off the left side of the plane. I'm eventually going to replicate this on my "backup" Ultimate 40S, same engine, but this time using a Macs tuned pipe.


Did you replace the stock wheels?

I have 2 3/4" rubber wheels on mine now so it handles grass with aplomb. I am about to switch over to 3" Ultra-lite threaded wheels instead though, as the rubber wheels add quite a bit of weight.


Before landing take it high and get very comfortable with it's stall speed.

If you are using an 11x6 prop it will be a very fast plane so you must get used to where the actual stall point occurs. It will be far slower than you expect if you are flying around at normal speeds... however this plane will tip stall when it gets too slow, so always come in under some 10-18% power, and cut throttle just over the runway threshold, then let it float down.


You'll love it with a properly tuned .46.

this delta he bought has slide on wing panels. they bolt on from inside the fuselage. it has (i guess thats what their made of?) carbon support rods and a wing support tube. i've never seen a delta like that. he thought the wing panels had to be epoxied to the fuse. also the fit of the right wing panel to the fuse side was not good. something was not sguare, probably the root rib. i started to buy one of their .25 arfs but i thought $17.95 for standard ground shipping was somewhat extreme.

I hate to say it, but if you need the manuals for more than C.G. and throws, you really should consider another ARF first.

I don't have the Delta but I and others in my club have purchased many NP models.

Recently I purchased the Ultimate 120R and the finish is EXCELLENT. The hardware could be better, but for the price I paid, I'm that much better off!

Why? Well since I had purchased this plane from someone else I would have paid more and then gone out and paid for more expensive hardware. At least with the N.P. Plane I've recooped the cost of the hardware.

I also have the Yak 54 1.60, the Ultimate BiPe, etc. all are fine. Find me an ARF 1.20 Ultimate for 180.00 elsewhere PLEASE! I haven't found one.


A friend has the large fiberglass P-40 Warhawk. He is 1/2 way into construction.

The thing is a beaut. It's so nice that I'm trying to get him to purchase the realistic looking exhaust headers for it.

opjose, Well I got to maiden my Ultimate yesterday, Thurs. I met up with a good friend of mine that is also my instructor. He took it off first and was very surprised at how docile it was. I ended up putting my 40 la on it with a 10x6 prop. I will use this engine till I get used to flying it. Then after refueling I got to fly,with buddy box even though I am trusted, I wanted the extra security just incase. wow it flew just great. It was a little slow on the rolls and of course verticals were hendered by under power BUT it was a great time none the less!!!! It turned out that I wanted to keep refueling and flying over and over. But due to tx battery I had to give it up after 6 flights. What a shame...lol.
Now for the interesting part. I have now added longer servo arm on the ailerons and taped the joint between them and the wing. I have also added end point on the Tx but am still only at 3/8" movement. Since you have gotten 3/4" you must have some seriously long control horn and the hook up way down low...lol. Maybe one of these days but not to soon for me. Also I suspect that when I get around to adding the 46 things will pick up speed. aka roll rate speeds.
I'll keep you posted, thanks for any and all info to improve on a great little bird!!

Glad to hear your maiden went good. To get the movement up on mine I increased the rates to 150% on the Tx.
With the Evo 61 and 13x6 prop mine leaves the ground in ten feet and straight up out of sight. I like the extra power to get out of trouble. The Ultimate is a great plane.

Talk about a "well run business"........ They have a nitromodels advertisement that popped up getting into this forum just now. The ad is for a YAK model that looks like it's a 46size. Not much solid info in the ad, so you click on it to find out things like wingspan, engine size, whether or not it's got a fiberglass fuselage etc. The ad starts filling your screen with tons of pictures. Pictures are good, but you want to find out details that'll decide whether or not you'd buy the sucker. You scroll down and find a couple of lines between the pictures here and there.

You find out that the YAK has "charisma". Hey, I've always wanted a model plane to take to parties. Wonder if it also drinks and smokes? And that the YAK is an airplane that's easily maintained. Jeez, a bunch of the guys I fly with never maintain any of their models, wonder if this easy maintenance would get them to start. And wonder what nitro thinks ought to be maintained on their YAK. But there doesn't seem to be any information at all about the specifics of the model. Well, what the heck, I've been looking for a YAK that size for a couple of months now and guess what..... this one is sold out. And it's the one I've seen for about a month now that was sold out first time I saw it.

Talent shows.

I have 35 flights on my Ultimate now. Got it to flat spin last weekend that was realy cool. Pucker factor rating 1-10 that was a 10

Well after a week or so of flying every chance I got I now have the bugs worked out. I was having a problem with flutter. Turns out it was in the ailerons. I had a friend make up some control horns with weights on them. I mounted them under the bottom wing and all flutter is gone. I have since gotten a Hitec metal gear high torque servo for the ailerons and taped all joints. Wow !!!! It's no twist but dang what a spin!!!! I am very pleased with the setup I am running (40 la and a 10x6 wooden prop). Its a little hot to land and when the throttle is cut it will almost stop in air.. lol
I have got to get another for a back up!!!

Flying yesterday and heard something strange brought it in for a close look and found the skin half off the top wing. Got it down ok. Will add cover checking to the pre-flight check list.

My father Got the 64" Super Chipmunk, and oustide of the pointless instruction manual it is a pretty decent plane. My biggest buff was that it need a pretty large shim under the left wing to get it level and some of the plasic hardware is petty crappy. Flight preformance though made up for all the headaches in the shop. It has a K&B .60 swinging a 10x7 3 blade, can do some wild thigs with it but slow it way down on landing. We also have one of the .40 ultimate on the way, I'll post the issues on it to.

chipmunk rating scale 1-10

Instructions............0- Not even rateable
Quality...................8- pretty nice plane
build......................5- it was'nt to bad
flight......................20- flies well worth the effort!
Looks.....................10- looks as good as it flies

Chipmunk sounds cool..Kinda strange, at least to me, about adding a shim. I have seen several other planes from them and all share several common things. Directions are all at the same level. A few headaches during the builds. But all seems forgotten when it take to the air.
Glad to here about the addition af a Ultimate. I have found a new favorite and the Ultimate 40 is it..small, easy to carry and a thrill to fly. Have fun!!

You got FLUTTER on those little ailerons????

I've flown the Ultimate 40S with both a .46 TH engine and a .52, at very high speeds, and never had any flutter problems.

The gap should be so minor that tape should not make any difference.

I did rip out a wing strut after doing some particularly violent maneuvers. The struts hold down is particulary weak on the Nitro Planes model of the Ultimate.

I'm going to put a small piece of angled balsa along the bottom of each hold down, epoxied in place to prevent this from happening again...

BTW: I lost aileron's in that maneuver, but I was able to bring the plane down using small rudder movements and elevator. The long control horn had popped right out... I don't know if I lost the screw or I stupidly forgot to put it in... duh. The plane was unscathed though.

Re: Backup...

That's how it starts! Then they multiply by themselves.

I thought the same thing and found that there was too much slop in the linkage. The ailerons were just vibrating. At full throttle you could hear them on a fly by. But mine does fly just a little fast with the .61

Yeah that makes far more sense.

I noticed that when I first tested the Ultimate 40S' (both the WM and the NP ones) that the aileron linkages would get a strong harmonic vibration at particular RPM ranges. It would cause a 'wizzing' sound in flight but it was not the destructive flutter always talked about.

I then replaced the servo with a higher torque one and use longer control horns with stiffer linkage wires and the problem went away for the most part.

Even now the linkage wires make a not unpleasant singing noise as the plane goes by.

But I've run this sucker full throttle nose down from high altitudes and never had real flutter.

On one plane I put the linkage wires inside thin fuel tubing to stop the harmonic vibration, borrowing a trick from the heli guys. This worked.

I opted for the WM Ultimate 40s. I started with an OS .50sx and a 12x4 APC but recently switched to a 13x4 APC. I like the 13 far better. The speed this little bipe wants to fly at is amazing. I have my battery in the fuse behind the lower wing to achive balance and thats a 1700 MAH 6V Nmh pack. Anyway the WM 40s has put up with a lot of abuse (aka hard landings) with no damage other than having to re bend my landing gear. It would have ripped the gear block out of most ARFs. Anyway after I figured out that I set my Expo rates the wrong way (made it more sensitive to inputs) I fixed that and this bipe is a pleasure to fly and always a croud pleaser. Oh and the 50sx with either prop gives this bird rocket like virtical performance.

The skin comming off my top wing saved my plane. I was triming off the old skin and noticed some movement in the wings. Gave a slight pull and the left strut pulled out of the wing. Checked the right side and it was bad too. Epoxied them back in place.

Note to self; DO BETTER JOB ON PRE-FLIGHT CHECKS

Good thing I dont fly full size aircraft

The landing gear block should be re-inforced a bit when you build either plane... I've ripped them out on both the WM and the NP version, but a small piece of hardwood stops this altogether.

BTW:

I reenforced the tail with carbon fiber struts put in much like you would with rigging wires.

This has made the tail amazingly sturdy.


Two weeks ago at the field I caught the edge of the runway sending the 40S flipping end over end, to the oos and aws of spectators.

Everyone though that the plane would have major damage.

As I walked over to pick it up, I stated that it would be fine, and that it was quit sturdy.

Sure enough I picked it up, refueled it and took off again.

Three people came to me with note pads wanting to know where to buy the plane, as they were amazed at how well it held up.