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Oct 10, 2019, 07:19 AM
Registered User
When I was learning to fly with rudder and throttle I could have used this advice.

One thing I did do, not "aggressively", was to use S turns into the wind to keep my plane from drifting downwind. It's just like glider pilots do on the slope. Turn into the wind, let it go a little cross wind, drifting back a bit, then turn the other direction into the wind, and repeat. That really helped me; before that I wouldn't fly till it was almost dead calm because if the plane got down wind my orientation confusion would make it very hard to get back.
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Oct 11, 2019, 07:07 AM
Culper Junior
That was how we always flew escapement and galloping Ghost. Upwind. That was if the radio failed due to range problems it would drift downwind back into range. It’s funny, but even today I always fly upwind.
Oct 11, 2019, 09:08 AM
I like real wooden aeroplanes!
Sundancer's Avatar
Yes, in the days of single channel and non-too-reliable radio range it was always prudent to stay upwind, and I used to tend to still do that even after I got my first reliable propo gear. What broke me of the habit was 15 years of competitive thermal soaring where, if you wanted to win, you just went with the lift wherever it went - and that was usually downwind of course - to the limit of your eyesight, and fortunately mine was pretty good in those days. My rule of thumb when thermalling off downwind was to constantly assess the angle which line of sight to the model was making with the horizon. If the angle was increasing, then fine, keep on going as long as you can see it. If the angle was staying constant, time to head back. If the angle was decreasing, PAST time to head back. And never come back up the same track that you went downwind on, because there will probably be sink following on upwind of the lift you have been using.
Oct 11, 2019, 04:54 PM
Registered User
In regard to the "aggressive s-turn", some models with the Ace pulse system and magnetic actuator can be rocked so that the climb is suppressed with little change in direction. I don't think a small servo would be quick enough.

Somewhere on this forum there is a video of mlbco flying his R/O, 13", Cox .010, Sperry Messenger - a master-class in R/O control.
Oct 12, 2019, 11:06 PM
Registered User
JMP_blackfoot's Avatar
Quote:
Originally Posted by Footrrot
In regard to the "aggressive s-turn", some models with the Ace pulse system and magnetic actuator can be rocked so that the climb is suppressed with little change in direction. I don't think a small servo would be quick enough.
Somewhere on this forum there is a video of mlbco flying his R/O, 13", Cox .010, Sperry Messenger - a master-class in R/O control.
https://www.rcgroups.com/forums/show...&postcount=136
Oct 13, 2019, 12:14 PM
B for Bruce
BMatthews's Avatar
On the aggressive S turn for coming back upwind.

Calling it "aggressive" might be an overstatement and lead to the wrong thoughts on it. When I fly my own RO models (.010 and .049 with no throttle) the idea of the S turns was to turn just enough to kill the natural power climb and build up some speed. And the turns were done so that I never let the nose go past around 45 to 50 off the return line. This keeps the speed up without letting the model climb and makes fairly short work of getting back upwind. It doesn't work in the glide though. So don't let the model get downwind other than during the first part of the flight if you're running wet power with no throttle.

A big part of rudder only flying with or without throttle is having a bit of a pre-flight plan as to where the wind is from and how far you're willing to let the model drift. In a strong wind, which is certainly flyable, it's not a bad idea to climb at first, which will see the model drift downwind, and once up around 100 ft start the flattening "S" pattern to claw upwind a good distance and then let it climb a bit more for altitude to use from a spiral dive to start the fun stuff.
Oct 13, 2019, 12:54 PM
Registered User
Bruce,
for my part I don't fly when the speed of the wind is higher than the glide speed of the model. If you do you finish down wind at the end of the airfield!
I don't understand how you do to go against the wind?

regards
Guy
Oct 13, 2019, 04:43 PM
Registered User
In the action I am trying to describe the model hardly deviates from its course at all but just rocks laterally. Not all models will do it. I think the requirements are a fairly low aspect ratio, generous dihedral, and a quick rudder action. A servo operated rudder will spend too much time transitioning and too little at full throw. The rocking rate is roughly 1cps.

The little model in the photo does it well though I haven't flown it for a long while due to CB interference. It is a scaled down and simplified version of a design by Howard Boys who was a UK pioneer of pulse-rudder and magnetic actuators in the 1950s.
Last edited by Footrrot; Oct 13, 2019 at 05:49 PM. Reason: vanity again
Oct 13, 2019, 09:49 PM
B for Bruce
BMatthews's Avatar
Quote:
Originally Posted by uram
Bruce,
for my part I don't fly when the speed of the wind is higher than the glide speed of the model. If you do you finish down wind at the end of the airfield!
I don't understand how you do to go against the wind?

regards
Guy
When under power on a rudder only model most of the power is used to climb. The model with this sort of trim will tend to climb at or about the same speed as the glide. But in this case "at or about the same" is generally SLOWER than the glide. So if we point into the wind and let it climb we drift downwind.

But if the model is not climbing we have speed well above the glide speed. And that's where a back and forth "S" turn ends up covering ground at a much faster speed than letting our rudder only models just stay in a climb. Yes, some of that is lost to the side to side movement needed with a rudder only model to keep the nose down. But overall the model when S turning strongly enough to keep the flight path level will make its way back upwind or fight further upwind just fine. The trick is to do this with just enough turn that the altitude doesn't keep changing on us. And that is tough to do with the modern setups with just a button to act like an old time escapement. A quick thumb can do it but it's a lot easier with just one servo and a regular ratio with proportional sticks.

Of course as I suggested we rudder only flyers also need to plan ahead. The goal is to get up wind and stay there since once the engine quits we loose our power source other than spending altitude to glide down faster. So paying attention and knowing when it is too windy for the model we have is part of the flight planning. But as long as the wind is at or only slightly above the stall speed flights can still be made by getting upwind while under power and stay there.

And in such conditions our planned landing approach might need to be modified. Normally we like to turn downwind, then cross wind and finally onto our final. But in heavy winds that are roughly the glide speed that is not a wise method. Instead we point mostly into the wind and if we need to lose some altitude it is better to just turn off the wind slightly and "crab" out to the side so from the ground the model is moving across the wind without gaining or losing ground. But we cover ground to the side and then back again such that we drop to our landing height and come in over the field and let the model touch down. All while mostly gliding into the wind.

This last description of flying in heavier winds should not be a surprise if you have also flown gliders. When it's really windy at some point the wind is strong enough that with a rudder and elevator glider we do not want to turn downwind, cross then back into the wind for the final approach. Instead we'll crab out to one side or other and back to bleed off excess altitude. Just with a glider we typically have an elevator to help.

Did that come through in the translation? Or within your English level? I'm assuming your native language is French. If something is confusing ask away.
Oct 14, 2019, 07:35 AM
Registered User
That was very good and corresponds to my recollections.

I recall instructions on some early rudder planes to decrease the wing incidence on windy days, or increase stab incidence, since often they were attached with rubber bands.

That would reduce the climb tendency and increase the speed.
Oct 14, 2019, 01:06 PM
Registered User
Your explanation is good so I shall attemp to do that in the future but with 10 Knots maxi.

Yes I am a froggy living in France in the middle of the British gang who has invaded my country

Regards to all

Guy
Oct 14, 2019, 01:59 PM
I like real wooden aeroplanes!
Sundancer's Avatar
It's not an invasion Guy, just an entente cordiale!
Oct 14, 2019, 03:27 PM
B for Bruce
BMatthews's Avatar
Quote:
Originally Posted by uram
Your explanation is good so I shall attemp to do that in the future but with 10 Knots maxi.

Yes I am a froggy living in France in the middle of the British gang who has invaded my country

Regards to all

Guy
By 10 knots (11.5 mph or 18.5 kph) I think I'd likely already be on the ground or only finishing the day with one last rather careful flight for my rudder only flying. If that's what you consider max wind to fly in then I tip my hat in respect at your chutzpah... And if you think that's not a fast wind then I think you've been hanging around that British Contingent too long... It's a wonder the British Isles haven't been blown away yet from the Old Warden videos I see most of the time and the couple of times I've been over in Britain and Scotland....

Roughly 17 years ago I had a trip to France with a group that was there to do a canal barge and bicycle trip through the Loire valley. The weather was kind to us and as a result it was a great time and some truly beautiful villages and small town visits. We cycled through farm fields to the local town for a visit then back to meet the barge at a new spot on the canal each time. Each town started with a visit to the local boulangerie and a second meat shop for cold cuts and cheeze for lunch if the boulangerie. Fresh baked croissants like only the French can make.... My mouth waters again at the thought...
Last edited by BMatthews; Oct 14, 2019 at 03:33 PM.
Oct 14, 2019, 04:56 PM
Registered User
To return to the point (boring I know - sorry), we seem to keep harking back to the familiar S-turn routine to help penetrate upwind under power, R/O. This works and for many planes is the best you can do.

However, if you are able, then rock.


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