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Guidelines or formulas for how much water to dump in narrow or weakthermal racing?



 
 
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  #21  
Old May 16th 20, 11:45 PM posted to rec.aviation.soaring
Jonathan St. Cloud
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

On Saturday, May 16, 2020 at 9:09:25 AM UTC-7, Charles Ethridge wrote:
I understand...BUT...the leading pilots in Condor simulator racing are all, as best I can tell, holding onto their water as long as possible, i.e. they aren't leaning toward the conservative side. This is probably because it is virtual racing, and no one is going to break a real glider (or their real bodies) if they make a water mistake. If I dump water and they don't, they invariably beat me in the cruise segments and especially in final glide.

That's why I was looking for rules of thumb and formulas when racing, as opposed to cross-country.

Ben


While Condor is an Excellent tool, many people, fly different on Condor than they would or could in real life!
  #22  
Old May 17th 20, 02:43 AM posted to rec.aviation.soaring
Dave Nadler
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

On Friday, May 15, 2020 at 1:18:47 PM UTC-4, Charles Ethridge wrote:
Hi, all.

When racing a typical 1-2 hour flatland race in, say, a Diana2 or Ventus3-15 (15 meter ships with water ballast and flaps), are there any guidelines or formulas for how much water to dump, particularly when thermals are weak or narrow?

Here are the parameters I'm thinking would apply (but I'm no expert yet- thus the question):

1. Average thermal strength
2. Average thermal width
3. Average distance between good thermals
4. Height band for the day

I was hoping to find something on this subject in a glider racing book or the Diana2 flight manual, but no luck so far finding either googling.

Ben Ethridge


If your chronic leecher is underneath you, dump.
  #23  
Old May 17th 20, 04:07 AM posted to rec.aviation.soaring
[email protected]
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

As long as you are happy with your climb rate then keep the water. The advantage in the cruise of flying heavy requires no skill or effort but achieving the advantage of lower wing loading in the climb does and it is easy to throw it away through lack of technique or lapse of concentration. As soon as you are unhappy with your climb rate, and don't expect better conditions ahead, then dump it bit by bit until you are. The happiness factor includes things other than theory or algorithm such as comparison with other gliders (if any), conditions ahead, current altitude, terrain below, pilot risk aversion level etc. Stuff that may not seem so important in simulation as in real life.
  #24  
Old May 17th 20, 02:25 PM posted to rec.aviation.soaring
[email protected]
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

It build character to climb heavy and then decide to dump just as you head out in cruse ;-)
  #25  
Old May 17th 20, 04:10 PM posted to rec.aviation.soaring
Jax
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

Here is a paper about flying with water, it is for lower performance gliders but the concepts remain the same.

https://keepitsoaring.com/wp-content...er_ballast.pdf

Other interesting articles by the same author
https://keepitsoaring.com/the-speight-papers/

  #26  
Old May 18th 20, 07:48 AM posted to rec.aviation.soaring
[email protected]
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

If in doubt, try to err on the light side. The penalty for being too light is a slower task, but the consequence of being too heavy could be a land out.
  #27  
Old May 18th 20, 01:31 PM posted to rec.aviation.soaring
Andreas Maurer[_2_]
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Default Guidelines or formulas for how much water to dump in narrow or weak thermal racing?

On Sat, 16 May 2020 09:09:22 -0700 (PDT), Charles Ethridge
wrote:

I understand...BUT...the leading pilots in Condor simulator racing are all, as best I can tell, holding onto their water as long as possible, i.e. they aren't leaning toward the conservative side. This is probably because it is virtual racing, and no one is going to break a real glider (or their real bodies) if they make a water mistake. If I dump water and they don't, they invariably beat me in the cruise segments and especially in final glide.

That's why I was looking for rules of thumb and formulas when racing, as opposed to cross-country.

Ben



Condor is great, but its thermal model isn't correct at low altitudes
(thermals don't get a lot weaker or tighter close to the ground),
therefore there's hardly any penalty if you get very low.

I once got a 6 kts thermal after (!) an outlanding when I bounced back
into the air... and completed my 150 miles task.


Cheers
Andreas



  #28  
Old May 18th 20, 03:58 PM posted to rec.aviation.soaring
Charles Ethridge
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Posts: 33
Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

On Sunday, May 17, 2020 at 11:10:25 AM UTC-4, Jax wrote:
Here is a paper about flying with water, it is for lower performance gliders but the concepts remain the same.

https://keepitsoaring.com/wp-content...er_ballast.pdf


Wow! Excellent article! Adds a lot of "why" to the "what". I need to re-read it a few times to fully absorb. I will read his other articles you link as well.

Thanks!
  #29  
Old May 27th 20, 07:18 AM posted to rec.aviation.soaring
2G
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Default Guidelines or formulas for how much water to dump in narrow orweak thermal racing?

On Monday, May 18, 2020 at 7:58:26 AM UTC-7, Charles Ethridge wrote:
On Sunday, May 17, 2020 at 11:10:25 AM UTC-4, Jax wrote:
Here is a paper about flying with water, it is for lower performance gliders but the concepts remain the same.

https://keepitsoaring.com/wp-content...er_ballast.pdf


Wow! Excellent article! Adds a lot of "why" to the "what". I need to re-read it a few times to fully absorb. I will read his other articles you link as well.

Thanks!


Keep the water until you are about to landout.
 




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