mbilar1

I'm just a little confused about this: I have acquired 3 trainers:

Hobbico Superstar RTF, OS 40LA, 10 X6 prop, 60" wing, 5.5 lbs.

Older kit-built Great Planes PT-40, Magnum .46 GPS, 10 X 6 prop, 60" wing, 5.5 lbs.

Older kit-built Thunder Tiger Skykark, Magnum .40 GPS, 11 X6 prop, 65" wing, 6.0 lbs.

My question is the heaviest plane is the TT Skylark, with the bigger prop, but .40 engine. The PT-40 has a .46, but the smaller 10" prop. The TT Skylark actually has the lighter wing-loading as calculated by the bigger wing, but swings a bigger prop. I have all the engines tuned and dialed in and running perfectly with 10% nitro fuel.

What are the flying differences expected with the different combinations? Wouldn't it make sense to put the .46 on the heavier trainer with the bigger prop? I've only had one lesson in the air with and instructor with the Superstar, but to me, it flew too fast, admittedly there was a 12 mph wind, but it kept getting too far away too fast. I want to fly close in and land slow while I train.

alan0899

G'day Mate,
The speed the plane flys is not really related to the engine size, it is determined by the elevator trim & the throttle setting, if it is flying too fast for you, tell your instructor, & get him to trim the plane so it flys slower, eg. more up trim, less throttle, trim for straight & level at about 1/2 throttle, or you may need less throttle than that, that's what the trims are for.

bigedmustafa

My Feedback: (2)

The difference in power between a .40 ball-bearing engine and a .46 ball-bearing engine like your two Magnums really isn't all that great. The two Magnums should weigh about the same, and they will perform about the same, even with a 15% difference in displacement between the two.

Any one of these trainers should fly nice and slow so long as the engines are fully broken in and they can idle at a nice low rpm level. You might like the way the Superstar flies a little better if you change the prop from a 10x6 to an 11x4 or 11x5 on the .40 LA. A larger, shallow-pitched prop will load down the engine and prevent higher rpms with the throttle wide open while not producing too much thrust throughout the power band. The APC 11x4 sport prop is a good choice, because it's fairly heavy for an 11" propeller compared to Top Flight or Master Airscrew props.

One of the reasons you're training with a flight instructor is because model airplanes are capable of fast speeds and keeping up with them is challenging while you're learning to fly. You can adjust your propellers and try to dial in your engine settings for good, smooth slow flight. You need to be patient though, and keep working with your instructor so that you can keep up with your plane.

What good would it do to slow your trainer down so much that you can only fly the slowest planes imaginable? If you have any interest in sport planes, aerobatics, pylon racing, pattern flying, combat, warbirds, or most anything else in this hobby, you're going to have to learn how to keep up with your plane. It seems fast now, but keep training and your instructor will have you flying your plane (as opposed to your plane flying you) sooner than you think.

Safebet

My Feedback: (12)

Very good advice, Biged.

I just soloed and one of the things you have to learn (it comes with practice) is you fly the plane, not the other way around. Don't worry so much about the speed. Learn to stay ahead of the plane. Anticipate you next move. If the wind veers it off track, bring it right back.

Remember, when you are flying "downwind" the plane is going to move much faster, so you know that the next turn is going to come up quicker. Up wind, slower. Turning from downwind to upwind will require more "up elevator" to keep the nose from falling. Upwind to downwind will require less.

It's these things you learn. And, remember, I said it comes with practice.

The main thing is never take your eyes off your plane, and watch what your plane is doing with different control inputs. Example, try making a turn while going downwind. Nice
easy bank. Watch the nose as it begins to come around without adding any up elevator. You will see the nose drop. It's kinda hard to see these subtile flight path changes when your first learning because you are concentrating so much on just keeping up with the plane and trying to get it to go the direction you want it to.

Relax, and you take control of that plane. You literally are holding it in your hands. (TX)

Welcome to RC

Jim

Safebet

My Feedback: (12)

PS: This shows my newness. In the above post I said: "Turning downwind to up wind (nose into the wind) will require more up elevator." That is backwards. It will require less because when coming into the wind more lift is created. The plane sometimes will baloon up in a strong wind.

I am new so I can still make mistakes. The point of the post is to assure you all will be ok. Just begin to really watch your plane ans see what it does in different conditions.
You will learn quickly.

Jim

Insanemoondoggie

I flown my LT40 with three different engines ST GS40, Evo .46 and a Magnum 52 four stroke. On the 2 strokes I used a 11x5 prop which did help slow it down some for landings.
The Magnum 4c pulls it the best with a 12x6 APC. I also moved the CG back and maxed out the throws. Woke the trainer up , and made it more fun to fly.

felixone

Don't stress too much about the speed. You didn't really mention what you had the throttle at when you said it was too fast. I only soloed last weekend, but during the entire time I worked with my instructor I flew just over half throttle. There were times I opened it up (take offs, pulling out of an aborted landing, etc), but for the most part I flew it slow. At first if I went to full throttle I too felt it was going too fast. However, the first time out after soloing I noticed something halfway through a flight...I was running at full throttle! I never backed off after my take off. It was handling fine, and I was able to track it even at full speed. Although, once I realized I was wide open I did pull back to about 3/4 throttle

My point is...The throttle is there for a reason, if you are not comfortable at full throttle slow it down. Just be careful not to go too slow or you might find yourself landing before you want to

If you are already running at partial throttle, then I definitely suggest getting a slower prop.

Good luck, many safe flights, and just as many safe landings!

bruce88123

Your airspeed is the same whether flying upwind, downwind or crosswind assuming you do NOT touch the throttle and maintain altitude. If you make your turn using the same bank angle on all turns you will not gain/lose any more altitude on one turn for a given elev position than on any other turn.
That being said most pilots want thier TURN RADIUS's to look similar or symetrical. In other than calm wind conditions this will call for varying bank angles in different turns. During the steeper banked turns you will need more elev to maintain altitude than required in the flatter banked turns. This is caused by the fact that part of the wings lift is generated toward the inside of the turn in the bank and less goes to vertical lift.

There is no more lift going into the wind than when flying downwind.

jetmech05

true airspeed does stay the same...but with a tail wind your ground speed increases, visa a versa with a head wind ground speed decreases. most folks get ground speed and air speed confused.
You will learn to fly closer in, just relax and progress with your instructor....you're gonna have a ball.

B.L.E.

If you were flying in a dead calm, but from the deck of an aircraft carrier that was steaming along at 20 knots resulting in a 20 knot apparent wind, it would feel exactly like flying in a 20 knot wind.
Likewise, if there was a 20 knot breeze on the ocean and that aircraft carrier you was flying your plane from was going downwind at 20 knots resulting in a apparant dead calm, it would feel exactly like you were flying in a dead calm.