If that were the case then there would be no need to have a Southern and a Northern Hemisphere compass, just make them all have extra compensation adjustment. It is not like the South Pole is negative and the North is positive. Your needle will point to the Poles as "North" regardless of which one. The card has to be reversed in order for the orientation to be correct for indicating South and North relative to the North and South Poles.
-----Original Message----- From: krnet-boun...@mylist.net [mailto:krnet-boun...@mylist.net]On Behalf Of Serge VIDAL Sent: Tuesday, August 08, 2006 9:01 AM To: KRnet Subject: Réf. : RE: KR> Drilling template for Precision Vertical Card Compass Colin, I believe that's not the way it works. The Earth works, roughly, as a giant magnet whose ends correspond to the South and North poles. So your compass does not invert when you go from one hemisphere to the other. The needle always points along the magnetic field "lines", and these are roughly parallel to the ground and to the meridians. My guess is the reason for building special compasses for Northern/Southern Hemisphere must have to do with compass behaviour at high latitudes, where the field lines are no longer parallel to the ground, and start "dipping" towards the ground when you fly towards the pole. I suppose this requires clever mechanical compensations, which may not be symmetrical. Serge "Colin Rainey" <brokerpi...@bellsouth.net> Envoyé par : krnet-bounces+serge.vidal=sagem....@mylist.net 08/08/2006 14:40 Veuillez répondre à KRnet Remis le : 08/08/2006 14:40 Pour : "KRnet" <kr...@mylist.net> cc : (ccc : Serge VIDAL/DNSA/SAGEM) Objet : RE: KR> Drilling template for Precision Vertical Card Compass Serge It is my understanding that it will work fine as the magnetic attraction will be to the South Pole, but the indications will be reversed: your North indication will be to the SOUTH POLE, so as long as you know that is what you are seeing, then no confusion. All the quirks of the compass, ie: lead and lag reverse in the Southern Hemisphere. You might get really good at math conversions when given headings by approach control, cause you will always be 180 degrees out. -----Original Message----- From: krnet-boun...@mylist.net [mailto:krnet-boun...@mylist.net]On Behalf Of Serge VIDAL Sent: Tuesday, August 08, 2006 7:47 AM To: kr...@mylist.net Subject: KR> Drilling template for Precision Vertical Card Compass I just made a printable paper template for the Precision Vertical Card Compass. As usual with me, it's a Microsoft Powerpoint file. I'm not a draughtsman by any account, so precision not garanteed. But it's free, so anyone interested, just shoot. (And by the way, could anyone tell me if that compass is going to work well in the Southern Hemisphere, although it is a Northern Hemisphere P/N?) Serge Vidal KR2 "Kilimanjaro Cloud" Paris, France _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html " Ce courriel et les documents qui y sont attachés peuvent contenir des informations confidentielles. Si vous n'êtes pas le destinataire escompté, merci d'en informer l'expéditeur immédiatement et de détruire ce courriel ainsi que tous les documents attachés de votre système informatique. Toute divulgation, distribution ou copie du présent courriel et des documents attachés sans autorisation préalable de son émetteur est interdite." " This e-mail and any attached documents may contain confidential or proprietary information. If you are not the intended recipient, please advise the sender immediately and delete this e-mail and all attached documents from your computer system. Any unauthorised disclosure, distribution or copying hereof is prohibited." _______________________________________ Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html
