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RFields5421

Hello i have two question about GPS

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Hello. when i fly to an airport with GPS approach. How can i setup the GPS to go fix by fix from the IAF. i select the approach in the GPS them i activate but once my airplane start to circle around the fix. And the other question is how can i use the approach button in the Autopilot. Thank for the help.

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Hi Hugo,To set up the autopilot to fly a GPS route from fix to fix you first have to enter your fixes into a flight plan by using the Flight Planner available from the Free Flight screen you usually start with. I gather from your post that you have already figured out how to set up the autopilot to fly the GPS route, so I won't reiterate that procedure.When you arrive at your destination you can fly a GPS approach by selecting an approach from the PROC menu on the GPS. You'll see a number of different approaches for the different runways, and all you have to do is select the one you want by using the cursor keys, and then hit the Enter key. If you have trouble you will find some useful info in the Learning Centre.It is worth noting that selecting a GPS approach will only give you lateral navigation, the GPS will not fly the glide slope so you will have to trim for the descent manually.Alternatively, and to answer your second question, you can set up the autopilot to fly the glide slope by entering the ILS frequency for the runway into the NAV1 radio. You will find a list of frequencies in the facilities directory available on the map. You will have to commence this procedure from a position below the glide slope so it is best to start quite a few miles back from the runway, say between 10 and 20 miles depending on how fast you are going. It's best to commence the procedure with the autopilot in HDG mode and use this mode to line up on the runway. In your HSI, or your NAV 1 indicator you will see a bar move across the guage which tells you when you are lined up on the runway so it is really useful in poor visibility conditions. When you're lined up, and when you've got the glide slope indicator active (the other bar on your NAV1 guage, or a little tick on the side of your HSI) then you switch the autopilot from the HDG mode to APP. The autopilot will then fly the glide slope all the way down to the runway.Experiment a little if you get lost, I'm sure you'll figure it out.Mike.

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I'm assuming from your description that you have "Selected" the GPS approach and it displays on the GPS.Have you then clicked on the Proc button again and "Activated" the approach, so that it replaces any flight plan and waypoints you had previously?Once an approach is activated, the GPS will fly the approach down to landing with the NAV/GPS button in the GPS position and NAV selected in the Autopilot.However, a GPS approach does not have vertical guidance, the same as a Glide Path attached to a localizer - the two critical parts of an ILS.Normally when the GPS/ Autopilot puts your aircraft into a holding pattern over a IAF point, your aircraft is too high for that waypoint.FlightSim puts user aircraft in holding patterns when they are too high for landing/ waypoints, if an approach has been selected and activated.Once you lower you altitude, you should break out of the hold and as you lower your altitude, fly to the threshold.On a GPS approach, you have priority over AI aircraft, so I use them often.After Selecting and Activating the approach in the GPS, I can let the GPS fly the approach. As I cross the IAF and head toward the runway - if the runway has an ILS - I setup for an ILS landing. Note, ILS Landing, but GPS Approach.I am flying the GPS approach, with the Autopilot in NAV and the GPS/NAV switch in the GPS position.I have the NAV1 radio setup for the ILS frequency.I align the OBS with the runway heading.I have the HDG set for the runway heading.I have my ALT set for 1500 feet above the runway.Once I'm past the IAF and near the ILS cone on the GPS:I switch the Autopilot to HDG.I switch the NAV/GPS switch to NAV.I click on the APPR button on the autopilot.The HDG and the ALT lights should go out as the aircraft starts to follow the virtual localizer and glideslope down toward the runway.At some point before touchdown, turn the Autopilot power OFF. If you are using AutoThrottle, turn it OFF.Make the last few feet before touchdown a manual landing/ flare. If you time it right, you can just flare a bit and land smoothly.By having the HDG and ALT set, should you have to go around, all you have to do is turn on the Autopilot power, turn on HDG and ALT and apply pleny of throttle.You should have your aircraft setup for a missed landing/ go around on every landing attempt.

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