Official Freewing Twin 80mm/90mm A-10 Thunderbolt II Thread

[flyAA]

We've already seen many times on this forum that "professional pilots" know Jack Schitt about flying RC planes. They crash more than the average beginner because their heads are filled with "real" plane characteristics. I'll save my popcorn, thanks.

PS. I know ground and airspeed aren't the same. I never said they were. I was only using ground speed to show what example I was trying to convey.

I wasn’t trying to be disparaging towards you. Sorry if i came off that way.

Much agree that that full scale flying has little to do with RC. I have almost ten thousand hours and crash RC planes my fair share lol.

But I when it comes to the downwind turn, RC and full scale are the same bc the aerodynamic principles are the same. There are many articles on the topic.

Cheers!

https://www.flyingmag.com/pilots-places/pilots-adventures-more/last-word-downwind-turns-really

https://www.planeandpilotmag.com/article/myth-bustin/#.XNBdyxYpDDs

[xviper]

I wasn’t trying to be disparaging towards you. Sorry if i came off that way.

Much agree that that full scale flying has little to do with RC. I have almost ten thousand hours and crash RC planes my fair share lol.

But I when it comes to the downwind turn, RC and full scale are the same bc the aerodynamic principles are the same. There are many articles on the topic.

Cheers!

https://www.flyingmag.com/pilots-places/pilots-adventures-more/last-word-downwind-turns-really

https://www.planeandpilotmag.com/article/myth-bustin/#.XNBdyxYpDDs

Understood. Appreciate the clarification. :Cool:

Besides the differences in flying characteristics between a "real" plane (which you sit in and can feel in the seat of your pants) and a model plane (which you watch from the ground), therein lies another key ingredient. "Instrumentation and other electronic assistance". I flew with a friend in his small, single engine, low wing "something" (can't remember the name of it now). That was several decades ago and even then, the one thing that still stands out in my mind was when we were coming in for a landing. As he was about to touch down, he was gauging his proximity to stall speed (at least that's what I thought he was doing) by pulling back on the stick repeatedly (several meters off the deck) until the little voice from the instrument panel yelled out "stall, stall, stall". Scared the crap out of me. Looking back at it, I conclude that this device was telling him that he was exceeding the acceptable angle of attach and was about to stall, which I guess, is what he was trying to do to get that desired landing. To me (a layman), it seemed that exceeding the angle of attack and stalling was very similar. It didn't matter which it was or what you called it, the plane was near or at the point of NOT flying anymore. The air going past the wings from leading edge to trailing edge was no longer at a speed that sustained proper lift. Whether it be from too much angle of attack or the airspeed slowing down too much, the same result occurred. We, as model plane flyers, don't have that luxury of being in the seat of the plane and feeling that point of "non-flying", so we can only observe what we think is happening.

[Aros]

Precisely why I stalled my Corsair and needed new retracts. I am usually quite good at staying above stall speed on my models but this particular flight I somehow struggled comprehending how close I got to stall speed and before I could react, BAM she dropped like a brick and folded the gear. Nothing can replace being in the seat and feeling what is happening. All we can do as RC pilots is view what we think is happening and adjust accordingly.

[F22trainer]

If you are doing it properly the stall warning should activate prior to touchdown. It is calibrated to 5-10 knots above the stall speed, therefore as the pilot begins the flare and reduce power in a full size aircraft, the stall warning should be audible in order to stall the airplane at the same time the wheels touch.

[Aros]

If you are doing it properly the stall warning should activate prior to touchdown. It is calibrated to 5-10 knots above the stall speed, therefore as the pilot begins the flare and reduce power in a full size aircraft, the stall warning should be audible in order to stall the airplane at the same time the wheels touch.

We need stall warnings on our radios! We have telemetry, why not stall warnings? :P

[themudduck]

I think I'll pipe in here, on the discussion about stalling RC planes on the downwind turn to final. I've got a few decades of experience and I'm an instructor at my club.

So keeping in mind that everyone has an opinion, and I'm certainly not saying that anyone else here is wrong, I just want to add my 2 cents.
I have taught this to my students many, many times! (and I agree 100%, students who are accomplished full-size pilots are absolutely the worst RC students.)

First, we're talking about landing when there's a breeze. This doesn't seem to be much an issue in calm conditions. So anyway, this thing happens when we're flying models because of what we're doing - we're flying completely with hand-eye coordination, obviously we don't have any instruments that help us with what we're doing. And what we're doing is, when we're flying that downwind leg we are watching the plane and we're trying to get it slowed down for landing. We're reducing throttle, but the plane is still moving too fast! (If we were driving an RC boat on a fast river, we could see the rushing water, but in our case the air is invisible.) So its just a matter of perspective you see (remember, we're only using our eyes) - it looks like the plane is flying too fast when in reality its being carried along by this river of air (the wind). So we reduce the power some more, and the plane's still moving at what appears to be a good speed for making that final turn. But the reality is that we are observing ground speed. And so we make that last turn and the plane just falls out of the air because we've bled off all the airspeed. And it seems like a complete surprise.

Of course, aerodynamically you can say that the inside wing stalled first because the outside wing is moving a little faster through the air in the turn, and that's correct - but the reason this nasty thing happens is because of the optical illusion that we're dealing with. When we're flying in the wind, you have to imagine the river of air, and just let the plane do its thing, it will "look" like its flying faster downwind. Remember, that's an illusion, its not actually flying faster. It will also appear to fly a lot slower when you finish that last turn and come in up against the wind. So the solution is, you reduce throttle on your model the usual (normal) amount, and just fly it all the way around that base leg to final, and magically it will appear to slow down when you fly the base leg up to the runway. Never cut the throttle until you have flown all the way back to the runway and you're in position to land.

I hope that helps.
:Smug:

[Aros]

Great stuff themudduck!

Can you explain airspeed vs ground speed a bit? Always something I didn't quite grasp in ground school...

[xviper]

I think I'll pipe in here, on the discussion about stalling RC planes on the downwind turn to final. I've got a few decades of experience and I'm an instructor at my club.

So keeping in mind that everyone has an opinion, and I'm certainly not saying that anyone else here is wrong, I just want to add my 2 cents.
I have taught this to my students many, many times! (and I agree 100%, students who are accomplished full-size pilots are absolutely the worst RC students.)

First, we're talking about landing when there's a breeze. This doesn't seem to be much an issue in calm conditions. So anyway, this thing happens when we're flying models because of what we're doing - we're flying completely with hand-eye coordination, obviously we don't have any instruments that help us with what we're doing. And what we're doing is, when we're flying that downwind leg we are watching the plane and we're trying to get it slowed down for landing. We're reducing throttle, but the plane is still moving too fast! (If we were driving an RC boat on a fast river, we could see the rushing water, but in our case the air is invisible.) So its just a matter of perspective you see (remember, we're only using our eyes) - it looks like the plane is flying too fast when in reality its being carried along by this river of air (the wind). So we reduce the power some more, and the plane's still moving at what appears to be a good speed for making that final turn. But the reality is that we are observing ground speed. And so we make that last turn and the plane just falls out of the air because we've bled off all the airspeed. And it seems like a complete surprise.

Of course, aerodynamically you can say that the inside wing stalled first because the outside wing is moving a little faster through the air in the turn, and that's correct - but the reason this nasty thing happens is because of the optical illusion that we're dealing with. When we're flying in the wind, you have to imagine the river of air, and just let the plane do its thing, it will "look" like its flying faster downwind. Remember, that's an illusion, its not actually flying faster. It will also appear to fly a lot slower when you finish that last turn and come in up against the wind. So the solution is, you reduce throttle on your model the usual (normal) amount, and just fly it all the way around that base leg to final, and magically it will appear to slow down when you fly the base leg up to the runway. Never cut the throttle until you have flown all the way back to the runway and you're in position to land.

I hope that helps.
:Smug:

Very informative post.
Perhaps not something that a seasoned "real" pilot wants to hear.
This is a key point, one which I did not emphasize nearly enough in my post, except to cite the example of the difference in airspeed vs ground speed. If there was no wind whatsoever, air and ground speed would be similar (with the exception of things like convection currents than can mimic wind - in most circumstances, "wind" is created by differences in atmospheric pressure, differential heating of ground/air, bodies of water, etc.).

[fhhuber]

As a 15 yr old, living on a naval base, I was flying Control Line. An "old guy" came up and asked if he could try it. I said:"Sure!"

Then I started to tell him how the CL airplane worked. and he said "I fly Phantoms for a living, I can figure it ut."

Started it up... set the plane loose and he crashed it after 2 laps.
(cheap .049 sheet balsa model, 15 min to fix it)

For several months I could go around the base saying: "I can out-fly the CAG off the Enterprise" and he backed me up.

If you are not rated in type... listen to the person telling you about how to fly the type.

Years later, I was a new recruit at basic and met him on the sidewalk... The CC (Navy equal to Drill Instructor) was bout to go nuts when I just walked up and shook his hand and forgot to salute... But the Admiral didn't care. Poor CC didn't know what to do with me.

[F22trainer]

As a 15 yr old, living on a naval base, I was flying Control Line. An "old guy" came up and asked if he could try it. I said:"Sure!"

Then I started to tell him how the CL airplane worked. and he said "I fly Phantoms for a living, I can figure it ut."

Started it up... set the plane loose and he crashed it after 2 laps.
(cheap .049 sheet balsa model, 15 min to fix it)

For several months I could go around the base saying: "I can out-fly the CAG off the Enterprise" and he backed me up.

If you are not rated in type... listen to the person telling you about how to fly the type.

Years later, I was a new recruit at basic and met him on the sidewalk... The CC (Navy equal to Drill Instructor) was bout to go nuts when I just walked up and shook his hand and forgot to salute... But the Admiral didn't care. Poor CC didn't know what to do with me.

Now that, is style! ;)

[F22trainer]

I think I'll pipe in here, on the discussion about stalling RC planes on the downwind turn to final. I've got a few decades of experience and I'm an instructor at my club.

So keeping in mind that everyone has an opinion, and I'm certainly not saying that anyone else here is wrong, I just want to add my 2 cents.
I have taught this to my students many, many times! (and I agree 100%, students who are accomplished full-size pilots are absolutely the worst RC students.)

First, we're talking about landing when there's a breeze. This doesn't seem to be much an issue in calm conditions. So anyway, this thing happens when we're flying models because of what we're doing - we're flying completely with hand-eye coordination, obviously we don't have any instruments that help us with what we're doing. And what we're doing is, when we're flying that downwind leg we are watching the plane and we're trying to get it slowed down for landing. We're reducing throttle, but the plane is still moving too fast! (If we were driving an RC boat on a fast river, we could see the rushing water, but in our case the air is invisible.) So its just a matter of perspective you see (remember, we're only using our eyes) - it looks like the plane is flying too fast when in reality its being carried along by this river of air (the wind). So we reduce the power some more, and the plane's still moving at what appears to be a good speed for making that final turn. But the reality is that we are observing ground speed. And so we make that last turn and the plane just falls out of the air because we've bled off all the airspeed. And it seems like a complete surprise.

Of course, aerodynamically you can say that the inside wing stalled first because the outside wing is moving a little faster through the air in the turn, and that's correct - but the reason this nasty thing happens is because of the optical illusion that we're dealing with. When we're flying in the wind, you have to imagine the river of air, and just let the plane do its thing, it will "look" like its flying faster downwind. Remember, that's an illusion, its not actually flying faster. It will also appear to fly a lot slower when you finish that last turn and come in up against the wind. So the solution is, you reduce throttle on your model the usual (normal) amount, and just fly it all the way around that base leg to final, and magically it will appear to slow down when you fly the base leg up to the runway. Never cut the throttle until you have flown all the way back to the runway and you're in position to land.

I hope that helps.
:Smug:

Since nobody else brought it up let’s throw this in the mix:

coordination and angle of bank - either too much or not enough rudder to match the angle of bank accelerate the stall and the higher the bank angle accompanies an increase in stall speed, but that is due to load factor.

you guys are all saying the same thing, we don’t have instrumentation or kinesthetic feel of the airplane from the ground. The combined axis of roll, pitch and yaw change couples one or more axis and when one is changed, others are also sometimes exaggerated.

Anyone want to talk about Dutch roll?

[xviper]

Anyone want to talk about Dutch roll?

Isn't that where you beat up a tourist in Amsterdam and take all his money? :Silly:

[bbolz]

Phantom, making little A-10'S?

[Elbee]

Isn't that where you beat up a tourist in Amsterdam and take all his money? :Silly:

I was thinking it had frosting and cinnamon on it.

[xviper]

I was thinking it had frosting and cinnamon on it.

I'd tap that! :Drooling:

[TiredIronGRB]

A short clip of my Rat-Hog from last night, I love this plane but for some reason I don't fly it a lot anymore :Straight-Face:

[themudduck]

Great stuff themudduck!

Can you explain airspeed vs ground speed a bit? Always something I didn't quite grasp in ground school...

I have a friend who has a Pietenpol (full size, i.e. he can sit in it) and he told me that sometimes while he's flying (at around 70mph air speed) he will often watch cars pass him on the freeway (ground speed).

Its because of the headwind.... and for some reason I find that hilarious. LOL

[Topshot19]

The load out is coming along pretty nice! Thanks dirtydee!

[Topshot19]

[Aros]

Looks sharp! And a little shout out to MRC on the engine nacelles, nice touch! :Cool: