blueapplepaste

My Feedback: (5)

As the title says I'm starting to build an Ultra Sport .40 and have a couple of questions, and if you have any general advice or tips/suggestions for the build, I'd appreciate them! I've read through the .60 build threads, but haven't found much on the .40.

I was thinking of modifying it for two servos for the ailerons as well as fully sheeting the wing, as I like the look of a solid wing more than being able to see the ribs through the covering, but neither of these I'm 100% sure on, as I don't want to add too much weight.

Am also undecided about retracts and adding flaps. Iknow on the .60, both come highly recommended, not sure about the .40 though, and again worried about adding too much weight.

I'm also only powering (for now) it with a TT Pro .40. Its a good little engine, and I think should fly her nicely, but I won't have gobs of power if things get too heavy.. So with retracts/fully sheeted wing/flaps/two servos/etc I don't want to weight it down so much that performance suffers.

Thoughts, advice, general suggestions? Thanks ahead of time!

MinnFlyer

My Feedback: (4)

I did the US60 build thread and it was my first 60-size. I have built 4 of the 40's

I had flaps and retracts on all of them and i highly suggest it. the added weight of the retracts will be a lot less than the drag created by haaving your wheels hanging down.

Sheeting the wing doesn't add a lot, and I like the looks of it too. What I did on one of them was to fully sheet the top, but cap-strip the bottom.

The 40 will be a little weak, but it'll do till you can afford something bigger.

redfox435cat

1) fully sheeted really isn't nesasaryy, it just added weight. There is enough sheeting were you really don't notice the ribbing but it's your plane.

2)flaps again unessasary, the only reason I can find is practice towards a warbird.

3) retracts for the taildragger does improve the looks, robarts through more expensive are allot cleaner to install, 40 sized mecanicals work just fine on it. If your going to go off grass ya might think about 60 sized retracts 3/16.

4)dual servos will just make for easyer aileron set up, it doesn't have oversized ailerons so the torque isn't nesasary. I'd say just upgrade the aileron servos to like a hitec 635. Or 2 standard servos and set up flaperons.

5) the tt 40 will pull it around ok, the 46 is a hair lighter

MinnFlyer

My Feedback: (4)

You WILL notice the ribs. I built one wing with the standard cap strips and the ribs were definitely noticable.

The flaps are not needed, but they sure to make for some pretty landings. Ken (RCKen) never added flaps. He flew my US 40 two years ago and said he'll never build another US without them

blueapplepaste

My Feedback: (5)

Thanks for the replies!

Ifigure it'd be weaker, but based on your other US .40s, do you think it will be under powered? I don't need unlimited vertical, but at the same time, don't want to have to fly at full throttle for mediocre performance.

MinnFlyer

My Feedback: (4)

It's really hard to say. Vertical will suffer, but the US is sleak and with a little added weight, it will do a good downline and high-speed pass and will have enough momentum to do a reasonable vertical pull out.

blueapplepaste

My Feedback: (5)

Thanks. I think I've decided to go with the retracts based on your advice. I do think they just look too cool retracted for that sleek look. I think for now I"ll leave it as is for everything else, as I'm still concerned about weight with that engine. I figure Ican go back and add flaps fairly easily down the road if decide I want them.

Now another question, which retracts? Are the great planes ones OK? Or should Ispring for more expensive Robarts? Ifly off a grass field, looks to be about the same as the field from your US .60 video as far as how the plane looked on the ground.

MinnFlyer

My Feedback: (4)

I really couldn't say how the GP retracts are. I only use the ones I made myself. If you don't want to add the flaps now, but plan on adding them later, build the torque rods into the ailerons (even though you're going to use two aileron servos) so that they will be there later to control the flaps.