On Monday, February 15, 2016 at 4:45:15 PM UTC+3, wrote:
On Monday, February 15, 2016 at 1:48:59 AM UTC-5, krasw wrote:
On Sunday, 14 February 2016 04:57:42 UTC+2, Dave Nadler wrote:
On Saturday, February 13, 2016 at 10:34:32 AM UTC-5, Soartech wrote:
Hint:
http://www.onlinecontest.org/olc-2.0...htId=185517315
See ya, Dave
Dave, What is your point here?
MacCready theory is not always applicable.
Consider:
- What are MacCready theory's assumptions, and when are these not valid?
- Why do good flights often beat expected MC speeds (after accounting
for start-finish altitude differential)?
Hopefully this will be covered in the V3 talk at the convention;
Tilo tells me by analyzing OLC piles of flight logs, the actual
behavior of top pilots shows this, thus better informs how the glider
should be optimized...
Hope this helps,
Best Regards, Dave
Are you saying that MC theory is not valid for gliding long distances using continuous lift?
Read Brigliadori as he describes extended glide. MC is based on a a model of climb and glide that does not apply directly much of the time, especially with higher performance gliders.
It was initially derived that way, but I believe it *applies* to other situations too.
If you are running along under a cloud street, the slow thing is to fly just under the clouds speeding up in the lift so you don't get sucked into them, and slowing down when that danger is past. The fast thing is to increase your MC setting (and fly it) enough that you fly fast and drop below cloudbase sufficiently in weaker lift that you can slow down and pull up in lift without entering the clouds.
For high performance gliders the main modification to MC theory is that the conventional output is "speed to fly". The real output should be "angle of attack to fly".
At speeds around 40 - 60 knots they are quite quickly the same thing. But over 100 knots it means that you are simply pulling increased Gs in lift and decreased Gs in sink and you might well pass through the area of lift of sink with very little change in airspeed.
Intuitively, you're "bouncing off" the lift. And sink can't rob energy from you while you're in a low drag near zero lift configuration.