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How to actually find lift is now on several sites...

Old 09-23-2011, 10:48 PM
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tobuy3003
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Default How to actually find lift is now on several sites...

In just the last year or so I now see some free info listed on various websites on how to stay up that is actually true. Easily found by using Google and the right search words. I know this info works because Ihave tested it. The info is not a method at all. It is just pure physics. It has to do with wind speed changes and timing your launch.

Its a shame that this info is not listed on the instructions that come with the highstarts that have been sold for so many years. After all, when you buy a highstart what else is it used for besides finding thermals?

Also a light weight glider won't help you when dont know that sink comes in cycles and stays in your area for a while. I see so many people struggle to stay up where Ifly with light weight gliders, but I actually have several lead strips under the wings on one of mine and long flights are easy by timing my launch and or waiting to launch. Bad air abounds.... avoid!


Old 09-24-2011, 06:19 AM
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A10FLYR
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Default RE: How to actually find lift is now on several sites...

What? No links?
Old 09-27-2011, 01:38 PM
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da Rock
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Default RE: How to actually find lift is now on several sites...

Fly in a straight line.

If something seems to cause a roll, turn into the roll. The something is lift and it's somewhere to the side that went up.

If the glider suddenly slows, it's just flown straight into it.

Pretty simple, really.

Now that you've found it comes the hard part.
Old 09-28-2011, 10:57 AM
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jetmaven
 
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Default RE: How to actually find lift is now on several sites...

get a vario and hope it sings the song you want to hear
Old 10-03-2011, 09:58 PM
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OzMo
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Default RE: How to actually find lift is now on several sites...

"I now see some free info listed on various websites on how to stay up" Are you aure they're talking sailplanes?
Ol Blue could be his favorite tablet

Seriously paractice is the best way. Real time exposure to conditions in your area is priceless. Becoming comfortable with your glider is really one of the best ways to FIND LIFT. If you are used to its reactions you will know when it hits lift.

All the tried methods come to mind, some of the key ones would be know the area's lift makers, fly during the best time of day for thermals, watch the birdies!
Old 10-12-2011, 02:25 AM
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da Rock
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Default RE: How to actually find lift is now on several sites...

Watching the birdies is one of the best. Our birdies around here are buzzards. It's really funny too. In the last month, one club has experienced an upsurge (pun intended) in interest in gliders. And in that time, the conditions for lift seem to be hiding out somewhere other than within reach of our field. The buzzards roost overnight nearby. They're apparently not early risers (yeah, intended) and that's led to some funny encounters.

Since all the new gliders are electric, our flights always include some pretty decent climbs. Although we haven't been finding any real good thermals, all of our flights will include a circle or two or three if we're desperate. Funny thing is, on poor lift days, the buzzards don't show much interest unless one of us repeatedly circles and especially if they add a bit of electric lift in the circling. Then lo and behold, we've got the buzzards flapping toward us. Seems they haven't learned when we're cheating with the motors. And seems they think we've found good enough lift.

We've never had any look back and bronx-cheer us as they discover the truth and flap away, but some day it wouldn't surprise me.
Old 10-30-2011, 07:12 AM
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Default RE: How to actually find lift is now on several sites...

Hi-starts don't thermal, gliders thermal. Why you would expect thermal soaring instructions to come with a hi-start is beyond me. I would expect that information with the glider.


But here is some info that you may find useful.


The key to long long flights is not catching a single huge thermal but being able to move from thermal to thermal as they die.

Get to know your flying field. Where are the thermal generators. They will usually be very wind direction dependent.

Try launching high then just cruise around watching the glider. If you find a thermal, work it for a little while, gain some height, then leave it and head off to where you think it came from and see if you can find another one behind it.

Work a thermal, gain some height, then leave it. Fly up wind a bit, then turn around and see if you can pick up that same thermal again. Remember it may not be in the same place as when you left it. It likely moved with the wind.

Put a ribbon on your antenna (72 MHz), on a stick or on a pole so that nothing interferes with the air flow. Don't launch, just watch the ribbon and establish what the prevailing wind direction is. Now, watch for the ribbon to change direction, say pulling 30 degrees to one side of the prevailing wind. If it holds there for a while, then returns to the prevailing direction you probably just witnessed the formation or the passing of a thermal. The bigger the shift the stronger or the closer the thermal.

The thermal may be exactly where the ribbon is pointing or it may be more up wind, say 90 degrees to the normal wind direction. This will fade out after a while. If it happens again, go launch and find the thermal. A small one will be close. A big one may be farther away.

If the ribbon reverses direction, then the thermal is forming directly up wind and is pulling so much air it is overcoming the prevailing wind. If you wait for a bit you may feel the air go calm and then get warm. You are standing in the center of the thermal.

When we fly hand launched glider contests we often set up a series of 10-20 foot poles with long streamers on them. The poles are set up around a launch area that is about 100 feet by 50 feet. Before the contest pilots launch they watch the ribbons. It is highly likely they are not all blowing in the same direction. This is a clear indicator of where you will find the lift.

A good launch with these gliders is 120 to 180 feet, so we are usually finding and working thermals that we find when were are fairly low in altitude. At this height they can be very small and narrow. It is not uncommon to pick up a thermal at 10 feet that is 5 feet wide and just forming. You turn in a very tight circle to stay in the core of the thermal. If the thermal continues to form and grow you can rise up till your plane is a dot in the sky.

Timing Thermals - Watch the changes and see if you can anticipate the changes. Are they regular? Thermals often run in cycles and sometimes they are very regular. I have been at contests where you could predict the cycle so well that when it was your turn to launch you could decide whether to chase the thermal down wind that the other planes were working, or go up wind and catch the one that was going to come through next. This is huge fun!

Back into the air - Using what you learned from the ribbon, launch and find the thermal. Work a thermal till it is down wind from you, but keep an eye on that ribbon. When it indicates another thermal, go see if you can find it.

Avoiding Sink - Get high, then leave it and come directly back toward yourself. Chances are you will fly directly into the sink that follows the thermal and you will lose altitude quickly. Do it again but exit 45 degrees to one side or the other and see if you tend to drop less. You should.
Sometimes you hit that boomer where it seems the whole sky is up and you could stay up forever. Those are great but they can get a bit boring. Having to chase one after the other to keep the plane up is the real challenge. If you get an hour flight needing multiple thermals you will find a real sense of accomplishment.

Getting low - once you have the ability to find and work thermals up high, limit yourself in height. 15 second climb. Now go hunting. Thermals get bigger and stronger the higher you get. So finding them down low is much harder. Do the same things I said earlier, but start lower and stay lower. When you get to twice your launch height working that thermal, break off and start hunting again.
When you get good at that, 8 second climb only and do it all again. If you can get a 10 10 minute flights off an 8 second climb you are really becoming a thermal soaring pilot! This low level work will help you save that flight that is failing, where the big thermal died and you are about to land.

At no time during any of this practice do you use the motor to reclimb. Cheating! If you can't keep the Radian in the air based on thermal lift, then you land and start over again. Now you are becoming a real sailplane pilot.

I had my Spirit out one day. I launched from a hi-start and immediately found a great thermal. After 15 minutes I was getting low and called out that I was landing. On the approach I caught a blip at 30 feet and turned. Up I went for another 10 minutes. I did that two more times. What a ball! (Ed called not landing ... again. What a show off!)

Go play. Go practice and ALWAYS have a watch to time your flights. I have a switch on my radio that I flip on launch. This starts a count up timer. I can also have a count down start at the same time if I wish. I also have one of these Talking timers. They are great, especially when you are flying alone.
http://<a href="http://www.talkingti...d/4</a></font>
The talking timer will announce the time as your flight progresses. And if you ever get into thermal duration contests where your time is for a specific period, like 10 minutes, you set this to count down. It announces every minute up to the last minute. Then every 10 seconds till the last 10 when it counts them off 10 to 0. On zero you touch the nose to the ground.

One caution. This thermal soaring thing is very addictive. No two flights are ever the same. You don't know how long you will be flying till after you land. I just love it!

> Thermaling for Beginners

BIRDS, THERMALS AND SOARING FLIGHT
> How Slope Soaring Works
From the full text of the classic FAA guide


Old 11-03-2011, 12:52 PM
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Bax
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Default RE: How to actually find lift is now on several sites...

Great post!

If you're very good and/or have a good day, you'd be surprised at what can be done. Back in the 80's, I saw Paul Carlson hand launch a standard Airtronics Aquila (100-inch RES soarer) and fly it to a tiny speck. That was the same year he won the top award at the AMA Nationals, with 1st place in 2-Meter Class, 2nd place in Standard Class, and 3rd place in Open Class...all with the same 2-meter glider of his own design, the Prodigy.

I still have the one I built hanging over my desk in my office!
Old 12-08-2011, 07:06 PM
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Default RE: How to actually find lift is now on several sites...

I agree.....the Prodigy is a nice 2Meter....light and penetrates a mild wind well...giving you time after launch, to roam and range out front ...thermal seeking. Balanced right ( it's a very narrow range) it indicates lift really well. I liked flying it against the glass slippers in it's hay-day. It's a shame it's not still in production. You just need the plans and a handful of balsa to chop out another one....it would be worth the effort.

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