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Any glider pilots out there?

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Old 27th Aug 2014, 01:53
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Any glider pilots out there?

I'm talking my written test tomorrow and came across a question while studying about glide ratio and tailwind. It said that if you have a glide ratio of 20:1 and are traveling at 40mph, if you have a 20mph tailwind it will increase your glide ratio to 30:1. I know that I should know this but can any one help?
Thanks
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Old 27th Aug 2014, 03:07
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There are many references on the web. G00gle is your friend.

This link explains things quite well:

aerodynamics of gliding
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Old 27th Aug 2014, 03:33
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So it's basically saying add half wind speed to glide slope?
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Old 27th Aug 2014, 08:07
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Basically it's saying that rate of descent is the same, but add tailwind to groundspeed. (Or subtract headwind from groundspeed. )
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Old 27th Aug 2014, 14:20
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I know about the ground speed with wind but I want to know how that affects the glide slope.
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Old 27th Aug 2014, 16:06
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Relative to the air, the glide is unchanged. But when using the ground as your reference, your glide angle will change.
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Old 27th Aug 2014, 16:43
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Your glide ratio is the ratio of ground speed vs decent rate.

Your decent rate stays the same regardless of any head or tail wind, however now you have a 20mph tailwind your ground speed has increased from 40mph to 60mph.

Since your ground speed has increased by 50% but your decent rate has stayed the same, you glide ratio has increased by 50% from 20:1 to 30:1.
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Old 27th Aug 2014, 21:52
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Thanks everyone.
I finally understand
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