lharvey

I would like to reduce the airspeed of my trainer a bit and am not sure of the best approach. Should I modify the wing, lighten the load or what? I am trying to get it down a bit so my son will feel more comfortable giving it a try. Sure enough though, he'll catch on and want to fly the wings off the thing in high gear shortly after. Anyway, any ideas to simply slow it's minimum airspeed and maintain flight?

Thanks.

CRFlyer

The simplist idea is probably to drop a pitch size or two on your prop. Just be sure to increase diameter a bit to compensate for the load reduction on your engine from the pitch change.

Kaos Rulz

Easiest and quickest is to just throttle back and re-trim plane. Better yet, if you have ATV on your transmitter, you could adjust so that the carb barrel does not fully open, but you have full Tx stick movement.

Miloh

lharvey:

listen to CRFlyer he has the correct fix for your question. the pitch is the second number in the prop size.
and this is how it works, the pitch for example in a 12 x 8 prop is designed to pull the plane at 8 inches for one revolution of the prop and a 12x6 would pull it 6 inches for one revolution thus lowering the pitch will slow the plane. by reducing the throttle will obviously slow the plane but the lower pitch will give what seems to be like a breaking effect after using a higher pitch. then going back to the higher pitch will give to feeling you have just put it in netural giving a coasting effect. you may or may not want to increase the length of the prop depending on the RPM's the motor will turn with a given prop. using a lower pitch prop will also let the motor stay more up in the power so when you slow if you should need to reapply power in an emergency it will be closer to the power range needed.
Hope this is clear.

Miloh.

Miloh

keep forgetting to check that little box to be notified.

Miloh.

Flypaper 2

If you can lighten the wing loading it will fly slower without falling down. Smaller servos, Smaller batt. pack, etc. If you can add another bay to the wingspan would help to get the loading down too.

3DFanatic

My Feedback: (5)

Lowering the prop pitch isn't the absolute answer. If there isn't enough airspeed, the plane just won't fly.

The best way is what Gord suggested. Smaller, lighter everythings.

Stick Jammer

Going down a size in prop pitch will surely slow it down some but you should be able to fly most trainers at about 1/3 throttle (depending on the engine of course) once it has some altitude. I'm not sure by your post if you've tried throttling back. Most beginners have the misconception that the plane needs to fly at full power.

Miloh

I guess It might help a little to know what kind of plane it is and what knid of motor it has and if any mods have been made.
One thing I can say with complete confidence is.... if it is a trainer is should not have to be rebuilt in order to train a youngster to fly it!!!!!!
lharvey: Maybe you should seek out a local club to help you so the helper could see what you actually need help with.

Miloh.

lharvey

Thanks for all the replies. Here are some answers to your questions.

The trainer I am building now is an Eagle II. It will have a Magnum 52 4stroke. I started building and flying after being out of the hobby for a little over 10 years. I had only a minimum amount of flying skills when I quit flying way back when. I have reciently joined a club and there are a great bunch of guys who I am sure would help me to make adjustments. I am just looking for some advice before I get too far along on building this plane and I only get out to the field once or twice a month...

Looking at the plane last night, I was wondering if cutting the ailerons in half and making a set of flaps out of the inner half would do more harm than good?

I have a Kadet that I have relearned to fly with and it seems to be a little fast for learning. I enjoy flying it but it sure seems to me that there is little reaction time as you get close to the ground. I am not afraid of it but just want to fly something a little slower while I get my son interested in the hobby. I like to tinker with the plane and would love making modifications but just want a direction to begin in.

Well, there is my history and reasons for slowing down an airplane. I am willing to extend the wing, add flaps, lighten the load, and on and on but just wanting to see if anybody has a suggestion that maybe they have had work for them.

Thanks guys and I really appreciate the advice.

Larry

DBCherry

My Feedback: (4)

The problem I see with using half the aileron width for flaps is, the chord of the ailerons (legth fron to back) is relatively small because the ailerons are full wing width. Cutting that in half span wise will substantially reduce the effectiveness of the ailerons. Flaps on that plane are also likely to be pretty ineffectual, especially if they're that same narrow chord.

Now, if you were to say, double the chord of the 'new' flaps and ailerons, it might make an interesting modification. Would it be worth it? Not to me, because it also entails major modifications to the wing. (I'd want to double up on a couple of the ribs at least to compensate for the increased flight loads of the larger surfaces.)

Rather than go through all that, spend a few dollars a buy a Sig Kadet Senior kit. That plane will slow down to near walking speed without having to make modifications.

Good luck,
Dennis-

hookedonrc

One thing I suggest before doing anything is check the RPM level on idle. I have an US 60 that I am just breaking in and on idle the RPMS are too high. On landing it takes forever to slow it down. Since I have only 2 flights on this plane and the engine, I wll be reducing the idle speed. On a trainer, it does not take much power to get it into the air, so you might just have a few to many RPM's on idle. If this is not the problem, you haven't lost anything by checking and can always to more radical changes if necessary.

Stick Jammer

Don't mean to repeat myself or question your abilities, but are you throttling back once the plane is air-born?

banktoturn

lharvey,

An Eagle II, built to spec, should be a fairly slow flying plane, which is to say it has a low stall speed. If you really want it slower yet, then increasing drag or reducing thrust isn't the answer, because neither of those changes will reduce the stall speed. Increasing wing area or adding flaps are the right answers. If you want to add flaps, taking the inboard half of the ailerons is a good way to go, but you probably do want more chord than the ailerons have. You could just use wider st ock than the ailerons are built from, and let the flaps jut back beyond the trailing edge of the rest of the wing. To increase wing area, adding a couple more 'bays' of span would be a convenient way to go.

Good luck,

banktoturn
a

Miloh

lharvey,

Hay Buddie you do what you want. I don't need to be jumped on here either. But in all frankness your trying to learn to fly??? the last thing you need to do is put flaps into the mix while your trying to learn to fly.
Simply put!! if you have a trainer??? Understand the word trainer and realize the plane is designed to learn on if you go complicating it with rebuilds and such all you are doing is making it something other than what it's designed to be.
If it's a trainer then you can learn on it the way it's designed and you should. just get your self an instructor and go get with it. Trying to make it easier to fly will just hold you back. If you want to fly, at some point your just going to have to get yourself a hand full and go fly. and the sooner you stop trying to reinvent the wheel the sooner you will solo.

Regards and good luck.

Miloh.

lharvey

Hello Jammer,
At one point in my earlier post I had a couple of sentences regarding the throttle speed but took them out of the post before I sent it thinking it was too long and that nobody would be interested. Thanks for the question. I have been flying a Kadet for a couple of hours stick time over the past couple of months now. That plane may be a bit heavier than what the Eagle will turn out to be but.. I fly it at about 1/3 open while doing some near touch-n-gos. It just seems that in order to keep the plane stable as it goes by, it is really moving.

I've had some really good answers by the folks here and can't tell you how much I appreciate it. I love flying almost as much as I love building but the real kick I get is from tinkering. If I trash a plane in the process, it just means more tinkering and one more item to mark off my list of things not to try again. After rejoining the local club, I had my instructor help me to get going again. After the first flight, his comment was that I don't need an instructor but rather tons of stick time. I had successfully regained my basics enough to solo but just need to refine my skills once again. That is the point where I am now and I am having a blast.

Please guys, I'm not second guessing anybody's advice here at all. I'm just enjoying the heck out of this hobby and am trying to find the best way to plant the seed of interest into my son. Everybody's advice is helping me toward that end and I truly appreciate it.

Blessings to all,

Larry

MinnFlyer

My Feedback: (4)

Here's the easiest thing to do:

Adjust the aileron linkages so that BOTH of them droop slightly (About 1/16"). This will increase both lift and drag, and allow the Eagle to fly slower.

This used to be standard practice, but with the advent of Computer Radios, a lot of people have forgotten the "Old Fashioned" way of doing things.