Dolphin flying

Steve is correct that we fly slower as we get lower, but that does not mean you should fly slower than your MC setting. In my first posting I stated that the MC should be set to the thermal strength you are willing to stop for. Rather than flying slower than an unrealistic MC setting, turn the MC down to what you are willing to take.

As Uncle Hank said there is no perfect answer that fits all situations, all decisions depend on many other factors including the conditions and terrain ahead.

John Cochrane's article "Just a little faster please" is a must read on the topic:
http://faculty.chicagobooth.edu/john...ring/index.htm

if you download the trace, you can see a remarkably long 100 mile run northward, below 4000 feet, with a -601 L/D for the last 76 miles

MB

On Saturday, February 13, 2016 at 11:18:41 AM UTC-5, SoaringXCellence wrote:
if you download the trace, you can see a remarkably long 100 mile run
northward, below 4000 feet, with a -601 L/D for the last 76 miles

The owner was kind enough to invite me to fly while I was waiting for my own ArcusM. I don't think many flew XC this day because of low bases and perceived weak lift. First bit of the flight I circled excessively while getting used to the glider (in which I only had a few hours). After I settled down, I had the owner turn off the very badly-behaved varios (a bad vario is far worse than no vario, but this upset the owner). Managed to string together various lift lines and avoid circling most of the flight.

We had to cut the flight short because of OD and some heavy showers, but still managed 460km and 17% circling IIRC.

The point is, under these conditions MC theory does not apply.
Consequently, neither does MC-derived STF in lift.

Hope that helps,
Best Regards, Dave

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

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?

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.
UH

On Friday, February 12, 2016 at 2:46:48 PM UTC-5, Jonathan St. Cloud wrote:
Was reading an article by Mike Borgelt that when flying through a thermal you will not circle in you should just fly the STF.

I have always slowed in such thermals, sometimes slowing to thermal speed while putting the thermal flaps. I do try to accelerate before I leave the lift. My thought being try to stay in the lift as long as possible while still moving forward, sometimes even s-turning to stay in large thermal but still moving down the course line.

Would appreciate any comments, critique, thoughts...

When I'm getting toward the bottom of my height band, I slow more for longer. Toward the top, the opposite.
All adjusted for how the sky looks ahead.
When the stick hand wants to turn- slap it and say "bad hand".
FWIW
UH

when I flew this past summer on a 4-hour and an 8-hour flight with a Very Experience Pilot (who shall remain nameless should I misstate), his technique on long legs (we had some 30 minute straight-ahead legs!) was to slow down in rising air, and initiate a turn. Once the plane caught up with the control inputs, he would decide to march on ahead if the lift was weak, s-turn (to keep the plane pointed generally in the right direction) when the lift was medium, and thermal when it was strong. YMMV. he very rarely thermalled, unless we really needed the altitude. --bob

On Friday, February 12, 2016 at 2:46:48 PM UTC-5, Jonathan St. Cloud wrote:
Was reading an article by Mike Borgelt that when flying through a thermal you will not circle in you should just fly the STF.

I have always slowed in such thermals, sometimes slowing to thermal speed while putting the thermal flaps. I do try to accelerate before I leave the lift. My thought being try to stay in the lift as long as possible while still moving forward, sometimes even s-turning to stay in large thermal but still moving down the course line.

Would appreciate any comments, critique, thoughts...

Gentlemen -

One thing to remember - there is contest flying and there is non-contest flying.

While I understand that the theory is exactly the same, I would expect very different tactics between a Nationals contest flight and an OLC flight.

Especially for an OLC flight where time or speed is not a critical component, I would expect a more conservative strategy would be found to be the norm.

Lou

On Saturday, February 13, 2016 at 2:18:18 PM UTC-5, MNLou wrote:
Gentlemen -

One thing to remember - there is contest flying and there is non-contest flying.

While I understand that the theory is exactly the same, I would expect very different tactics between a Nationals contest flight and an OLC flight.

Especially for an OLC flight where time or speed is not a critical component, I would expect a more conservative strategy would be found to be the norm.

Lou

I fly almost exactly the same whether practicing or racing. It doesn't pay to change my style.
For the best OLC flight you are still trying for the best speed given the time you fly so as to maximize points.
UH