Flying autopilot approaches

[Fnerg]

I have to admit, I'm a hop-in-the-ol-cockpit-and-fly kind of virtual pilot, but I'm starting to try and understand IFR. It's so complicated so, I'd like to ask a simple question regarding IFR flying, on autopilot, within 15miles of the destination airport, when do you set the auto pilot to "approach" once I've dialed in the approach on the GPS? Am I following the ATC instructions until I'm lined up on the glide path? Or can I set the approach on any time. Also if I fly GPS, when do I switch to NAV or do I?

I've tried the tutorials, and still am, but if can get answers to these specifics I will begin to understand what I'm doing better. Thanks.

 

[fliger747]

The usual scenario is that you change over when ATC clears you for the approach... Not a lot of help eh? One usually transitions from a heading vector to the final approach course, which works out well if the intercept angle is about 40 deg or so. IRL we are usually cleared to join the localizer, then when established to fly the approach.

FS planes in general seem to not be all that good in following the glideslope, adjustment of the throttle seems to be necessary in many cases.

Cheers: T.

 

[JO_Wingnut]

I've found when making an ILS approach, you want to be approximately 2000 - 2500 feet AGL and at an angle of less than 90 degrees to the runway, And I would recommend at least 5 to 10 miles out or farther to catch the ILS beacon. If the airport has a green feather designator on the GPS, it's best to be at least half way or farther on that marker on the screen. Have your nav radio tuned in to the ILS frequency and the plane will almost fly itself to the end of the runway. I usually shut off the autopilot just before touch down or you may over shoot and crash. That way you can do your final flair for touch down too. Also when you make your approach, set your autopilot to follow the radios (NAV) and not the flight plan or the approach won't lock on.

As for the throttle settings, I would find the checklist for that specific plane, and it will recommed the speeds required for approach. Most approach speeds are under 150 kts. Just watch that when the flaps and gear are deployed that you maintain speed or you will drop too low for the beacon to maintain hold. Also, make sure your altimeter pressure is set to local or it will either be too low or too high and may make it difficult if there are any landforms (hills) in the way.

If you are using the GPS to make your approach, it won't follow the glideslope. You have to make the approach using the radio.

 

[srgalahad]

I have to admit, I'm a hop-in-the-ol-cockpit-and-fly kind of virtual pilot, but I'm starting to try and understand IFR. It's so complicated so, I'd like to ask a simple question regarding IFR flying, on autopilot, within 15miles of the destination airport, when do you set the auto pilot to "approach" once I've dialed in the approach on the GPS? Am I following the ATC instructions until I'm lined up on the glide path? Or can I set the approach on any time. Also if I fly GPS, when do I switch to NAV or do I?

I've tried the tutorials, and still am, but if can get answers to these specifics I will begin to understand what I'm doing better. Thanks.

Those are actually several questions that don't really work together. You can do an instrument approach based on GPS OR ATC, but not both. If you're flying a GPS flight plan and use the approach programmed into the GPS it will do certain things. Using ATC it will lead you through others. If you use ATC then the GPS is simply a pretty moving map. In either case, you have to be on Autopilot APPR to intercept the Localizer and GS. One of the quirks of FS is that while running on "GPS" the NAV1 receiver and display are disabled.

More later,

Rob

 

[JO_Wingnut]

Thats why I mentioned to go off GPS to NAV when making the approach. It will follow the locallizer then. The GPS will only get you to the beam.

 

[MaddogK]

Can't remember if it was bad training, or a developed bad habit (while playing FS9) that has me going to NAV mode while making the turn to final and locking the otto once I'm level again. The GPS sometimes will get you over the runway but you'll have to fake the glideslope- and the map zoom is awesome with a RALT equipped a/c.

...but I don't trust machines, I drive the last 500 feet.

ALWAYS.

 

[JO_Wingnut]

So do I. I take it off autopilot so I can flare the plane for the last few feet on landing. I've found that the same method works if you use aircraft carriers and the approach. I can do a good trap every time using the methods I mentioned here.