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  #1  
Old 03-19-2011, 10:38 AM
agirard7a's Avatar
agirard7a agirard7a is offline
 
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Location: Newport, RI
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Default Glide ratio RV-9A?

I had read in an earlier post that a 9a
pilot had done some glide testing with a shut down
engine. Apparently the glide speed with
the least amount of decent per min. Was 70 mph
at a sink rate of 400 feet per min.

Am I correct in calculating: 70/60min. =
1.166 miles per min x 5,280 ft/mile=6160 ft per min
divided by 400 ft/min = 15.4 ??

Is 15.4 to 1 glide ratio correct or in a safe ball park
for a 9a? Seems pretty high? Obviously many factors
are involved ie. Weight, altitude, pressure, etc.

Seems that by default 10/1 ratio as in C172. Seems to be used.

Does anyone have an accurate glide ratio for a 9a,
Say at max weight?
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  #2  
Old 03-19-2011, 11:10 AM
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Mike S Mike S is offline
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Default

Quote:
Originally Posted by agirard7a View Post
Apparently the glide speed with
the least amount of decent per min. was 70 mph
at a sink rate of 400 feet per min.
Lowest sink rate per minute is not always the best way to look at it.

Lowest altitude lost for a given forward distance gained is pretty important.

This is one of those things glider pilots learn
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  #3  
Old 03-19-2011, 01:54 PM
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Default

For best glide in the -9A I use around 80mph.
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  #4  
Old 03-19-2011, 02:08 PM
alpinelakespilot2000 alpinelakespilot2000 is offline
 
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See the Cafe Foundation's report on the 9a. It's values are likely a lot more accurate than most of us can come up with. http://cafefoundation.org/v2/pdf_cafe_apr/rv-9a.pdf
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  #5  
Old 03-19-2011, 06:09 PM
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Sunriver Ken Sunriver Ken is offline
 
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Location: Sunriver, Oregon/Surprise, Arizona
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Default Denied Access

I tried the link to CAFE but was denied access. I wonder how it new me? Site manager must have been the pilot in the C-172 I passed last weekend. Poor sport.
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  #6  
Old 03-19-2011, 06:43 PM
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N941WR N941WR is offline
 
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Quote:
Originally Posted by Sunriver Ken View Post
I tried the link to CAFE but was denied access. I wonder how it new me? Site manager must have been the pilot in the C-172 I passed last weekend. Poor sport.
Try this link and scroll down to the RV-9A.
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  #7  
Old 03-20-2011, 06:59 AM
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agirard7a agirard7a is offline
 
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Default thanks

Thank you for the replies.

The Cafe report was excellent!
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  #8  
Old 03-20-2011, 07:52 AM
John R. Graham John R. Graham is offline
 
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Heh. No RV-7 report.

- John
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