GNS430 OBS and LEG Mode

hi everybody welcome to another Garmin 430 video this time I'm going to try to clarify the use of the OBS but so when it comes to using your GPS it's important to realize that there are two modes we call them a leg mode and OBS mode 99% of the time at least you're going to be in a leg mode and that is the default so I'll start by showing you leg mode and then we'll just throw in a couple of little examples of how you can use the o-p-s button ok so to do this I'm going to build a flight plan we're currently on the ground at the absolute airport in Abbotsford British Columbia we're just going to build a crazy little triangular flight plan from the airport out to the Abbotsford beacon so here we go into the flight plan page we'll just enter our first Waypoint as the absolute airport okay then the next Waypoint we'll put in the Abbotsford beacon which is only about four miles off the end of runway two five and then from there we'll hang a left turn we'll go down to the Watkyn vor which is only about six miles sets of the Abbotsford beacon and from there we'll hang another left turn and come back to the Abbotsford Airport now this little triangle is being purposely chosen to have some crazy tight turns in it just so that you can see how leg mode works so you notice that the first leg 2 4 6 then we make a left turn of about 40 degrees or so to 0 3 down to the Whatcom you are then our really tight left turn to 0 for 3 back up but to the airport ok so now you can see it on the moving map we'll just declutter the map a little bit for you so looks just like that and without further ado let's take off and start flying this so I'll fly about 150 knots which would be a typical speed for a light twin that you might be using in in IFR training okay so here we are in motion and we're currently about a quarter of a mile off track so I'll just zip over here and get right on track I've got the map set up to auto zoom so the the garment is choosing the the map scales currently at ten miles but as we get closer to the beacon it will zoom in automatically so the thing to realize here about leg mode is that the Garmin is going to do turn anticipation is going to take us smoothly from one leg to the next leg that's why it's called leg mode currently the active white point is the absolute beacon xx and as we go by xx the Garmin will automatically change the active weight way point to Whatcom you may be able to see already the dash line that the Garmin is calculating for the the turn anticipation we're down to a map scale of three and a half it will zoom in a little bit more and as we approach the beacon we'll be there in a few seconds the government will tell us exactly when to turn if we start when that if we start our turn when the Garmin tells us to we turn at rate one will fly right along the dash line so now you can start to see the dash line a little bit more clearly so see here comes the countdown says start to turn in eight seven six five four and we're going to make rate one turn starting right now and so we're in the turn now and our turn automatically takes us along the dashed line as we pass being the Abbotsford beacon here and about another five seconds you'll see the active Waypoint change from xx to hu H so there it goes now the active Waypoint is H or H on the map you can see the the magenta line has now switched to the next leg so the the magenta line always shows the next leg now notice you can see already the dashed line here we're not going to get anywhere near the Watkyn vur because this is such a crazy tight turn it's already got eyes turning back to the next leg and we're only four and a half miles from the Whatcom vor so again halfway through this turn the active Lloyd point will change and we'll be on our way back to the Abbotsford beacon so that's really good demonstration of leg mode and usually of course you don't make quite such crazy tight turns but as you can see it is within the garments ability to smooth out even a really tight acute angle like that now I'll just wait till I get turned around here and heading back towards the Abbotsford Airport which would be the end of our flight plan and then I'm going to demonstrate OBS mode setting the first thing that I'm going to do here once I get turned around is turn the the auto zoom feature off okay so to do that I tap the menu button and come down here to auto zoom turn the small knob change that to off hit enter we turn the cursor off and we're backs okay so now I have manual control of the zoom and now I'm going to show you how to use the direct button to access waypoints in your flight plan see here if I select the Abbotsford beacon as the active Waypoint and then hit enter the desired track two three six is what the Garmin calculates a rate one turn would put me on two three six but I'm going to hit the OBS button now using the OBS knob on my HSI I can set any track that I want so I'm just spinning the OBS knob on my HSI around here I can set anything I want let's say well I'll just leave it right there at two forty four and so now I'm just turning the airplane to intercept this this course that I've selected presumably and IFR flight there's some reason why you've chosen this course now as I come around I'm leaving in OBS mode for a moment just so that you can see how the garment is drawing a straight line or right through the Abbotsford beacon the magenta line is showing 244 inbound but if I leave it in OBS mode it'll just switch over to 240 for outbound when I get to the beacon but what if I just kick it back out of OBS mode now so as soon as I kick it back out of OBS mode goes back into leg mode and you can see the legs in my flight plan reappear I'm just going to slow down a little bit now so I'll slow down to about 120 knots and that should just change the turn anticipation a little bit remember I'm manually controlling the zoom now I'm just doing that for the purpose of this video generally speaking I recommend that you leave auto zoom turned on I just wanted to be able to control it a little bit here for the purposes of this demonstration so I'm just getting back on track if you look closely you may be able to see that the dashed line you may notice that since we're going slower now 120 knots instead of 150 that we were going last time the Garmin will calculate a slightly different turn anticipation path will pass a little closer to the beacon since we're going slower just zoom in a little bit more here okay gives us our countdown again we'll be turning in just a few seconds I won't sue min quite as much as the Garmin did you might get a better view of it this time okay so we start to turn now the Garmin says and as we pass a beam the beacon which will be just about now the active Waypoint will change again to Whatcom you see the magenta line change to the next leg and I really should zoom back out here okay so now you can see that turn anticipation leg the garment is going to turn me back into the Abbotsford Airport let's say I don't want to do that so I can put it in OBS mode again I'll just zoom that a bit so you can see a bit better so I put it in OBS mode and now once again I can use the OBS knob on my HSI to set any course I want maybe I'll set two to four it'll just turn over there and intercept that course now in this case I chose to do two four just to show you how completely crazy you can be because you know this might might be okay if I was going to fly by the Whatcom deewaar and then track out bout two to four but what I'm going to do now is take it out of OBS mode put it back into leg mode just so that you can see what happens here so watch when I turn OBS mode off and you can see the white line there is the next leg from Whatcom which goes back to the Abbotsford beacon we'll just zoom in a little there and so now this is a pretty darn crazy turn it's almost a complete 180 so the Garmin is doing some thinking about how its going to make that turn and how its going to smooth that out and it's coming to the conclusion that I'm crazy so here's the you're crazy message anytime you get that message that says steep turn ahead that's just basically the Garmin saying this turn that you've come up with can't be smoothed out what the heck is going on kind of thing so if I persist here and don't don't make some kind of a change what the Garmin will do is just let me get stationed passage and then turn so we'll just play this out and then this demonstration will be over so hopefully you're kind of getting the hang here of old BS versus leg mode most of the time you just want to build a flight plan that takes you where you want to go leave the energy in leg mode then it will automatically cycle from one way point to the next Waypoint to the next Waypoint you'll get your turn anticipation nice smooth flight sometimes if you have to adjust the track you'll temporarily put it in OBS mode usually in the enroute phase you don't leave it in OBS mode for more than a few seconds just long enough to change your track inbound to a waypoint and then put it back in leg mode so that because if you don't if you leave it in OBS mode right now if we were still in OBS mode as we passed the VOR here it would not have cycled ahead to the Abbotsford beacon which is what we wanted it to do I'm just going to zoom out a bit here so you can see as we come around the turn so you noticed as we passed the VOR the gns 430 cycled to the Abbotsford airport but if it had been an OBS mode it would have just stayed stuck on the Whatcom vor so usually the only time you want to leave it in OBS mode is if you're doing a holding pattern and to see examples of that you should watch some of my videos about holding patterns but for now you've had a pretty good look here at OBS verses leg mode and that's about it for this video so I'll see you next time

Channel: Ray Preston

Views: 80,900

Rating: 4.8528733 out of 5

Keywords: GNS430 LEG OBS IFR flight

Id: tmOw0V_DZ9M

Length: 13min 1sec (781 seconds)

Published: Tue Nov 13 2012