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Old Oct 30, 2012, 01:25 PM
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Windsor, Canada, near Detroit
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which way you turn?

i will appreciate if any of you could tell me which way you turn to get into a thermal, and then which way you do to stay in it.
or if you change direction for a reason.
i fly rc sailplanes, and i have been flying into thermals with free flight planes for many years trimming the plane to the left, as everybody does in free flight.
i also have been watching birds, and most of them turn left. sometimes among the flock, a few turn right. also recently watched 8 buzzards taking-off and climbing to the right into a thermal, all of them.
this intrigues me, so that's why am asking you guys this.
or if some1 can provide data on which way thermals turn.
i also have been told by a guy who flies paragliders that thermals turn same way as dust devils.
i hope this does not upset some1 thinking the question does not belong to this forum, but i can't think of a better place to ask it.
this is not a beginners topic.

if there are links of the topic please provide them.
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Old Oct 30, 2012, 05:14 PM
slope'n the Colombian Andes
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Colombia, Antioquia, Girardota
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Phil, nobody gets upset so long as you leave the Coriolis force out of it... : )
Which way to turn into a thermal depends on which side of the plane it's on. Very simplified: if the left wing lifts up, thermal is on the left, turn left; and vice versa.

Dieter Mahlein, ShredAir
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Old Oct 30, 2012, 05:39 PM
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Originally Posted by ShredAir View Post
Phil, nobody gets upset so long as you leave the Coriolis force out of it... : )
Which way to turn into a thermal depends on which side of the plane it's on. Very simplified: if the left wing lifts up, thermal is on the left, turn left; and vice versa.

Dieter Mahlein, ShredAir
that makes sense. thanks.

i still would like to hear from some1 who has any idea if thermals turn-and if so, in which direction, and if he can bring any reason why.
regards.
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Old Oct 30, 2012, 05:54 PM
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Thermals come in every form you can imagine and even more forms you haven't imagined yet. Keep it simple. Do whatever it takes to stay in the lift and if you are not in lift go somewhere else.

Rick
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Old Oct 30, 2012, 06:48 PM
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You turn the same way as the guy who got there first and from whom you are poaching the lift
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Old Oct 31, 2012, 12:08 PM
yyz
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Originally Posted by rshelby View Post
Thermals come in every form you can imagine and even more forms you haven't imagined yet. Keep it simple. Do whatever it takes to stay in the lift and if you are not in lift go somewhere else.

Rick
+1. I would only add that if you do sense any appreciable rotation (which would be incredibly difficult from the ground), circle against the rotation. Here's a link I had bookmarked that has some interesting discussion:

http://www.aviationbanter.com/archiv...p/t-24461.html

Mike

ps: Just stumbled across this one which really has some good info in it:

http://www.pas.rochester.edu/~cline/...ft_Sources.ppt
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Old Nov 02, 2012, 10:47 PM
Pat Chewning
USA, OR, Beaverton
Joined Sep 2009
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I find that I prefer to turn to the left simply because a left turn feels better (in more control) than a right turn. I think that is because a right turn shortens the thumb/finger, where a left turn lengthens the thumb/finger.

Left turns just "feel" better.....
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Old Nov 12, 2012, 09:40 AM
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Turn towards the lift to get to it. Turn whatever way you need to stay in it. If someone else is there first turn in the same direction as TK suggested. There is no right or wrong way. If you feel one side of your circle is stronger you can widen it a bit on that side to position yourself better or you can reverse rotation to move to that side. Kind of like a figure 8.

it's kind of like what way do you approach a buffet that has bacon. A mans gotta do what a mans gotta do.
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Old Nov 12, 2012, 03:08 PM
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any which way is ok

am beginning to see the light, thanks to all for your advice.
am reaching the conclusion that thermals just go up and there is no turn left or right inside of them, so you turn any way you find is better to stay put.

thanks again.
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Old Nov 14, 2012, 10:47 PM
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another view

and now a comment by pauliwog:
Hey, Interesting that you asked about which direction I circled because since that question has arisen on your thread I've been wondering about the most effective direction to circle my glider.

So, When I was out flying last (the same flying session that I posted about) I tried both directions and I couldn't really tell much difference but I "think" the plane may have moved a little slower from my perspective and turned a bit flatter when my plane was travelling clockwise in the thermals(as if viewed from above). At least twice I tried to change direction in mid thermal, but that didn't seem to work very well, I think they were small enough it just made me fly out and lose the thermal. The thermals I was in weren't very strong and did'nt seem to take my plane any higher than about 250 feet up so I think also the rotation speed was probably pretty low also.

My experience is that the much more visible vortex's of dust-devils and hay/grass-devils are more visible because these are the debris-filled bottom feeder columns below a MUCH bigger and fast rising mass of air above them where the "real" thermal is. I think that vortex is simply new air rushing in to fill a low pressure area left behind the buoyant large rising mass above.
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Old Nov 15, 2012, 11:22 AM
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I turn left most of the time as I am more comfortable and skilled turning that direction, especially in small or difficult thermals low to the ground or fast moving thermals in wind where I need to fly aggressively with lots of recentering and high bank angles at times. Same thing with bicycling, driving and skiing, I seem to be more skilled and comfortable in left turns than right turns, not sure why, coriolis??

If I enter a gaggle of planes turning right in a thermal and am in fairly close proximity I will turn right which is the rule. I still try my best to fly the "blue sky rule" but in crowded environments sometimes that is not possible (like at Visalia). If I "poach" a thermal and am clearly way below or above another glider I will turn any which way I feel is best, usually left 90% of the time. On small tight low to the ground thermals I generally will stay in the turn direction I entered and wait till it breaks loose and gets bigger and higher before doing a figure 8 to reverse direction to my preferred left turning.

I have observed dust devils many times and have attempted to fly into them. I think dust devils turn left due to coriolis effect and the ground plane forcing this turn of the incoming air mass like a tornado. Once the thermal gets very high I doubt it does much cyclone type turning as I cant tell if the thermal lift is better turning one direction or the other. That, plus I am generally quite a bit more efficient turning left. I have a suspicion that thermals come in all sorts of shapes, some like bubbles, some connected to the ground with one or multiple "roots" of feeder thermals feeding into a large rising mass of air. Some are broken up fragments of larger thermals. This I have encountered many times in XC flying using a vario. These "false positives" often fake out less experienced pilots and you need to keep flying thru them to find the real thermal they broke loose from even though the temptation to turn into them can be strong.

I could be way off on this but these are my observations and theories. Sure wish I could actually see thermals like we can see clouds, it would be real interesting. many times I have experienced a strange effect on blue sky days in strong lift nearly straight overhead where in my peripheral vision I can see a strange haziness surrounding my glider. It is always strong lift when I see it and if I look directly at it it dissappears, like dim stars do when you look at them directly. Thats as about as close to "seeing" a thermal as I get.

Steve
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Old Nov 15, 2012, 08:09 PM
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left?

another reason to turn left is that, somehow, as we have the heart on the left side and we get more blood on that side of the body, we tend to lean to the left. with the kind of dancing we used to do, we turned left; all(*) the races turn left; even horse races; indoor flying is the same; we climb into a horse or a bike leaning on the left leg. our mind is set on turning to the left.
and in my case, where i flew free flight and trimmed to turn left for any reason for many years, my mind is set to turn left.
but from all of this that am learning from all you guys am beginning to keep my mind open to try whatever seems more convenient at the moment, especially considering that thermals don't turn, as seems to be. never too late to start a new routine, as long as we practice enough to condition new reflexes. am learning that the mind does not grow older if we exercise it regularly, very much like a muscle. have you seen those documentaries from nova?
(*)edit: i have been told by 'flyonline' below that in 2 provinces in australia they race to the right. the only place in the world that i know. and that is not all over the country.
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Old Nov 16, 2012, 08:34 AM
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Do you only make left turns when driving, too?

UPS did a study that making right turns increased the effectiveness of their delivery drivers ... making right turns on red lights allowed them to make better use of their time.

Seriously, this idea that turning one way or another is simply a pilot's choice ... I have seen many over the years who cannot turn both directions well ... my advice to them is to work on the turns they shy away from. When the worst happens, will you only turn one way?

The comment of "I only turn left" is a sign to me to steer clear of that pilot.
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Old Nov 16, 2012, 10:44 AM
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open mind

Quote:
Originally Posted by tkallev View Post
Do you only make left turns when driving, too?

UPS did a study that making right turns increased the effectiveness of their delivery drivers ... making right turns on red lights allowed them to make better use of their time.

Seriously, this idea that turning one way or another is simply a pilot's choice ... I have seen many over the years who cannot turn both directions well ... my advice to them is to work on the turns they shy away from. When the worst happens, will you only turn one way?

The comment of "I only turn left" is a sign to me to steer clear of that pilot.
am not quite sure if you are addressing my previous message. what i do to avoid confusion, when am answering to some message and don't bring it in full, i type the post # so he knows about what exactly am talking. anyway, if you are talking about my message, please consider the 2nd part, where i say:

' but from all of this that am learning from all you guys am beginning to keep my mind open to try whatever seems more convenient at the moment, especially considering that thermals don't turn, as seems to be. never too late to start a new routine, as long as we practice enough to condition new reflexes. am learning that the mind does not grow older if we exercise it regularly, very much like a muscle. have you seen those documentaries from nova? '

i agree that it is very convenient to practice everything both ways, so we master then completely, but i haven't met any1 that does it. i myself, even if 1 can call myself ambidextrous (meaning using both hands equally), am aware that in some cases i feel more comfortable doing it with certain hand, and in certain situations i program 1 hand to specialice in something and the other in the complementary, so they do different things better and help each other, like driving and shifting gears. but i must add that if not changing gears i keep both hands on the wheel and i steer to the left with my right hand and to the right with my left hand. it draws less effort to me.
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Old Nov 16, 2012, 03:25 PM
Twisted and Confused
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Quote:
Originally Posted by phil alvirez View Post
all the races turn left; even horse races
Not necessarily - quoted from elsewhere:

Quote:
Racetracks in Victoria, South Australia, Tasmania and Western Australia are designed to be raced on in an anti-clockwise direction, while Queensland and New South Wales racecourses are clockwise.
And you guys drive on the RIGHT (sorry, wrong) side of the road

Steve
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