+Levacher Family Posted April 22, 2003 Share Posted April 22, 2003 Hello, In the GPS Garmin, which it is the difference between the term "to course" and "Course to steer" Both gives me the same indications. Thank you Quote Link to comment
Kerry. Posted April 23, 2003 Share Posted April 23, 2003 With no outside/zero affects both will be the same. Generally applies in aviation or boating situations. However in a current/wind situation the "Course to Steer" is that as it is affected by the current/wind etc component. In simple terms from your present position the "to course" might be due north (0 degrees) but if the current is running to the west then the "course to steer" will be somewhere east of north depending on the amount of currect. Cheers, Kerry. I never get lost everybody keeps telling me where to go Quote Link to comment
+Poindexter Posted April 23, 2003 Share Posted April 23, 2003 The "to course" on a Garmin unit is the recommended direction to steer to get back on your original course. It provides the most efficient heading to get back to the desired course (bring cross track error back to 0). "Course to steer" is as Kerry explained. Quote Link to comment
kb9nvh Posted April 24, 2003 Share Posted April 24, 2003 So course to steer is just your bearing from your current position to your final destination? Not your Course which is your bearing from your original position to your final destination??? Quote Link to comment
+Poindexter Posted April 24, 2003 Share Posted April 24, 2003 Not exactly. Course to steer is a nautical term which takes into account currents such as tide and leeway caused by the wind. Read Kerry's last paragraph again. If the current and/or wind is pushing you off course, even though your "pointed" directly to your destination then you would need to change your direction either to the left or right of your destination to counter these forces. That would be your course to steer. Correct on the definition of Course. Quote Link to comment
kb9nvh Posted April 24, 2003 Share Posted April 24, 2003 Well, I've run across this in a airplane. If the GPS knew the direction you were pointed (it cant know that, it only knows the direction you are going). Some aircraft gps's do know your "heading" that is the direction you are pointed (not the direction you are going). Then they can compute wind direction and speed (sweet!!!) If thats true then how can the gps know anything but the direction from where you are NOW to where you are going...seems like that would be the "course to steer". What else could it be? Quote Link to comment
Kerry. Posted April 24, 2003 Share Posted April 24, 2003 I don't think it was mentioned that the GPS knew which way you are/were pointing (it can't) just that if you were "pointed" directly to where you wanted to go and being pushed sideways then one would have to steer a course to counteract that and give you the most efficent way to stay on course to your destination. The GPS knows where you started from, where you wanted to go. It also knows where you currently are and heading (not pointing), which isn't really a heading as it's based on past information (sometimes referred to as Course Over Ground) but it's close enough (but still technically doesn't tell you a heading) given the time frames. Similar with Speed and Velocity Made Good as if one was heading directly to the destination with no influences then speed and VMG is the same. But with wind/current influences then your speed is different to your VMG and if one was going sideways (at a certain Speed & Course over Ground) then VMG to the destination is almost zero (or even negative). Cheers, Kerry. I never get lost everybody keeps telling me where to go Quote Link to comment
+Poindexter Posted April 25, 2003 Share Posted April 25, 2003 quote:Originally posted by KB9NVH:Some aircraft gps's do know your "heading" that is the direction you are pointed (not the direction you are going). Then they can compute wind direction and speed (sweet!!!) It can only know your heading if it has an internal compass or is getting heading data via the serial port, which is also where the wind data would be coming from. The Garmin Map76S can display depth, sea temperature, and boat speed and heading via the serial port. Quote Link to comment
kb9nvh Posted April 25, 2003 Share Posted April 25, 2003 Yep, I'm not trying to be difficult..just to understand the nomenclature. Seems like a couple of the items are identical on my gps V "course to steer" and ahh, I cant remember the other one..but they both read the same no matter what... I really dont know the purpose of "to course" either...seems like that would always be the heading you would take for the shortest distance back to your course line? I suppose thats worth something but when you reach your course you better make a "90" pretty quick or TO COURSE will instantly have you doing a U turn..LOL Yes, I think most of the GPS's for airplanes (The TSO'ed ones approved for flight navigation ) have interfaces to the directional gyro so they can know the way the airplane is pointed. On my airmap 100 I could put that in manually and then it would tell me wind speed and wind direction. Pretty Kool. Quote Link to comment
+Poindexter Posted April 25, 2003 Share Posted April 25, 2003 quote:Originally posted by KB9NVH:I really dont know the purpose of "to course" either...seems like that would always be the heading you would take for the shortest distance back to your course line. Not the heading for the shortest distance, but the most efficient heading to get back to your course. As far as course to steer, if you have no way to enter in current set/drift or leeway, then it would be the same as bearing to destination. My Map76S does not have course to steer, but does have to course. Quote Link to comment
kb9nvh Posted April 25, 2003 Share Posted April 25, 2003 Ahhhh, its all coming together now. You think my GPS V will take an external input from some sort of compass to give this extra functionality. Your 76S does some of that you say?? Quote Link to comment
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