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Old November 23rd 12, 07:55 PM posted to rec.aviation.soaring
Karl Kunz[_2_]
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Posts: 83
Default Glider Wings on a 747?

I would guess the best L/D speed to be in the 200-230kt range. So 1100-1300fpm.


On Friday, November 23, 2012 11:30:03 AM UTC-8, Peter Higgs wrote:
At 16:45 23 November 2012, kirk.stant wrote:

On Friday, November 23, 2012 10:00:08 AM UTC+1, wrote:


Great responses Papa3 & BobW. For those wanting to quantify glide


ratios,=


the Airbus A330-300 quotes a glide ratio of 18:1 with a double engine


fail=


ure. This includes the added drag from the RAT, an emergency windmill


that

=


extends to provide hydraulic and electrical power in such a situation.


Not

=


bad for a 238,000kg machine Casey




Yeah but what is the sink rate? And at what speed?




Kirk


66






Well lets do some Mathematics....



Estimated best L/D speed 160 knots

Therefore vertical speed = 160 / 18 = 8.89 knots



and that equals 8.89 x 6000 =53,333 ft / hr



which equals 53,333 /60 = 889 ft/min.



QED