PostFrontal Forum
PostFrontal Forum
LK8000_Support_Forum | Profile | Register | Active Topics | Members | Search | FAQ
Username:
Password:
Save Password
Forgot your Password?

 All Forums
 LK8000 International Support
 General Support
 McSpeed in wind
 New Topic  Reply to Topic
Author Previous Topic Topic Next Topic  

muanyag
Pulcino

17 Posts

Posted - 01/03/2015 :  21:22:36  Show Profile  Reply with Quote
Hello,
I do not understand why indicated SpMc (Speed MacReady)is lower in HeadWind than without any wind and why SpMc is higher in TailWind than without any wind.
I thought that it should be the opposite.
Thanks

davesalmon
Pterodattilo

United Kingdom
1620 Posts

Posted - 02/03/2015 :  09:58:07  Show Profile  Reply with Quote
Mc optimises speed through the airmass, doesn't make any difference if the airmass is moving (wind), except during final glide. So should be the same into wind and downwind.It is the same on my simulator.
Go to Top of Page

muanyag
Pulcino

17 Posts

Posted - 02/03/2015 :  10:10:32  Show Profile  Reply with Quote
Hello, thanks.
I learned that I need to fly faster in headwind and slower in tailwind. Reichmann told us that MC settings should be increased in headwind, which results higher MC speed.
I was not using the simulator, FLY mode with simulated position, speed height and vario data, provided by the device simulator application from my vario manufacturer. If the speed had the same I would have not written this, believe me.
Go to Top of Page

Alebu
Falchetto

Italy
105 Posts

Posted - 02/03/2015 :  10:44:51  Show Profile  Reply with Quote
Hi guys, many times I thought about that and, as far as I know all the flight computers behaves in this way. To be honest I don't understand why to consider the head/tail wind in the final glide only. It would be appreciated whether somebody could explain, thanks.

Go to Top of Page

davesalmon
Pterodattilo

United Kingdom
1620 Posts

Posted - 02/03/2015 :  11:03:26  Show Profile  Reply with Quote
Reichmann gives many different theories, and there are also others. However pure MC theory does not take wind into account. The difference with the final glide is that you are now gliding to a point on the ground, not in the airmass, so the wind has to be taken into account. If you are gliding into wind or downwind does now make a difference to the speed, and of course the climb rate in the last thermal has to be taken into account, to decide when to leave.
Go to Top of Page

muanyag
Pulcino

17 Posts

Posted - 02/03/2015 :  11:28:14  Show Profile  Reply with Quote
Thanks again, if we believes in this idea, the SpMC should be the same in any direction. My original post was that it is NOT the case in LK8000.
Let me try it in SYM mode as well, but first please tell me how to set any wind in SYM mode?
Go to Top of Page

bo.
Pterodattilo

843 Posts

Posted - 07/03/2015 :  10:33:52  Show Profile  Reply with Quote
From memory: Menu / Setup / Basic settings / enter windspeed and direction.

NB if you circle, the wind will be recalculated to nil wind from the absence of drift while thermalling. In other words the wind seeing will not cause drifting during thermalling.
Go to Top of Page
  Previous Topic Topic Next Topic  
 New Topic  Reply to Topic
Jump To:
PostFrontal Forum © PostFrontal - La community del Volo a Vela Go To Top Of Page
This page was generated in 0.13 seconds. Snitz Forums 2000

Since 2006, owned and maintained by PostFrontal S.A.S. di Giuliano Golfieri & c. - VAT ID: IT05264240960
THIS WEBSITE ONLY USES FUNCTIONAL COOKIES
Privacy & Cookie Policy