Date: Mon, 21 Nov 2011 20:46:36 +0000 From: Martin Gregorie <[email protected]> Subject: Re: [Xcsoar-user] About MC and tasks To: [email protected] Message-ID: <[email protected]> Content-Type: text/plain; charset="ISO-8859-1" On Mon, 2011-11-21 at 18:24 +0200, Ramy Yanetz wrote: >> After using XCSoar for a while I am very impressed with it but at the >> same time surprise that it assumes that everybody fly according to MC >> theroy and with pre defined tasks. Most pilots I know, which are >> serious XC pilots, do not set tasks. >> > Interesting: at my club its the exact opposite. Serious XC pilots always > declare a task if the day looks XC-able and expect to fly as much of it > as possible if the day turns out to be not so good. There's a good > reason for this: we are required to declare the task on the launch list, > along with a phone number and who is crewing (we often arrange mutual > retrieves) so people will know where to look if we don't get back and > haven't phoned in. > > If the weather isn't XC-able, but we still intend to fly, we declare the > task as 'local soaring' and stay within glide range of home. > >> and do not fly according to MC theory, which is way overrated. >> > Sort of agree: I don't know anybody you follows it as if carved in > stone. Where we fly in the UK its generally accepted that you're asking > for a land out if you set MC above 4 and that settings between 1 and > zero are a waste of time. Personally, not being particularly > competitive, I never set MC to more than "cloudbase/2000" where > cloudbase is measured in feet. This works well here. This year that > meant a max. MC setting of 1.8 - 2.5. > > Martin Many pilots at my small UK club fly set tasks or set their own task. If they want to fly the task at the best possible speed then McReady or modified McReady will give them the best chance. Occasionally, they will abandon the task or 'land-out' but like other games-of-chance, e.g. Poker, they will win over the long term if they play (fly) well.
If the objective is to complete a flight with no time limit other than sunset or the time that thermals will cease the parameters are different. Most glider pilots are 'local fliers' when conditions are poor. Then there are the many UK BGA Pre-XC Endorsement pilots who MUST remain within gliding distance of their home site. I have not tested the latest versions of XC Soar but the old versions with only my home airfield set in the task gave me a good indication of my required climb to reach it and, on one occasion of unusual misjudgement ;-), suggested a much better alternative. I do not understand the comments about HW/TW and thermalling drift not being considered when MC is set at zero. On final glide, seat-of-the pants I fly best L/D plus 40% HW. Significant TW means I fly at or near min. sink until the safety margin improves. I think Ramy mentioned a 2,000' cloud-base? Is cloud-base or best thermal height (AGL) an XC Soar parameter? I have been taught that in the top third I may fly at best estimated MC, middle third conservatively and bottom third save mode. Even at 1,300' to 2,000' we are constantly looking for land-out fields. Whilst the main aim of XC Soar is to help pilots to win competitions there are many users who want to fly conservatively and just get home. Alan . ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d _______________________________________________ Xcsoar-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/xcsoar-user
