View Single Post
  #21  
Old March 11th 18, 04:53 PM posted to rec.aviation.soaring
Dan Marotta
external usenet poster
 
Posts: 4,601
Default lightest DLG gliders



On 3/11/2018 9:31 AM, wrote:
On Saturday, March 10, 2018 at 7:19:47 PM UTC-6, wrote:
On Saturday, March 10, 2018 at 12:00:20 PM UTC-8, jfitch wrote:
But a mile is actually a useful unit, in context, as is a pound and a ton.

One degree of latitude is 60 nautical miles, and one minute is a nautical miles which is 6000 feet. Makes for some easy math measuring distance on a chart.

Not as simple using the metric system...

On 1:500 000 scale charts 1 cm represents 5km exactly. 1 inch more or less 8 miles.
On 1: 1000000 scale charts 1 cm represents 10km exactly 1 inch more or less 16 miles.

.... But you then have to carry a ruler with you in the cockpit or do you
have a body part that measures centimeters, e.g., the middle bone in my
little finger is very close to 1 inch so it's easy to approximate inches
on a chart, but why bother when I can simply use the minute marks to
estimate distance?Â* It is, therefore easy to see that 1 degree is 1.852
km.Â* Did you bring a calculator?

It's snowing outside... :-(
--
Dan, 5J