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Old March 2nd 05, 12:01 AM
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In article pu6Vd.84$Ci7.63@lakeread07, Chris W wrote:
Robert M. Gary wrote:

They all do. However, it is based on distance and runway length, not
"steepest glide". I'm not sure why you would want the steepest glide.
Don't you want to use your best glide speed and go to the nearest
airport? I guess the steepest glide would be straight down.


I guess I wasn't very clear in my first post. I know they all have the
nearest airport feature and give runway length. Lets say that I am
flying along at 14,000ft and the engine starts doing bad things. Since
I was stupid and wasn't paying attention, I ask my GPS where the nearest
airport is. It tells me that there is an airport 5 knots to my left and
10 knots to my right. What it didn't tell me is the runway to the left
was at an elevation of 10,000ft and the runway to the right was at an
elevation of 5,000ft. Lets make the math simple and pretend there are
6000ft in a nautical mile. To make the airport on the left you would
have to maintain a glide ratio of 7.5 to 1. To make the airport on the
right you would need to maintain a glide ratio of about 6.7 to.


One thing the GPS can't tell you is the wind speed. This could make a huge
difference whethe you would make an airport or not.
tom