Transition from 737 Autopilot GPS to ILS NAV and then Hand Fly - When???

I've watched Jack's youtube series which answered a lot of questions but here's what remains:

1. Let's say I'm approaching an airport in a 737-800 using autopilot set to GPS mode and I have an approach activated in the GPS. At what point do I transition from GPS to ILS (NAV Radio) in the autopilot? Is there a rule of thumb?

2. Now I'm using the autopilot set to the ILS NAV frequency and locked into APP mode. At what point should I turn off the autopilot and hand land the plane. I learned the hard way that turning off AP seconds before touchdown can cause some unintended yaw that I don't have time to correct?

TIA

I've watched Jack's youtube series which answered a lot of questions but here's what remains:

 

1. Let's say I'm approaching an airport in a 737-800 using autopilot set to GPS mode and I have an approach activated in the GPS. At what point do I transition from GPS to ILS (NAV Radio) in the autopilot? Is there a rule of thumb?

 

2. Now I'm using the autopilot set to the ILS NAV frequency and locked into APP mode. At what point should I turn off the autopilot and hand land the plane. I learned the hard way that turning off AP seconds before touchdown can cause some unintended yaw that I don't have time to correct?

 

TIA

I normally transition from A/P to hand flying about 2 miles out. Be sure your aircraft is prepped for landing.

5-15 miles out.

GPS has lined you up on the active ILS and you are in level flight beneath the Glideslope.

Transition to ILS approach

Deploy flaps and gear, set power level for landing

engage glideslope, stabilise the approach

Transition to hand flying and decouple the A/P

Fly last 2 miles under manual control.

An approach by GPS selected in the "approaches" page, is very different from an ILS landing.

If you have an approach selected, it will take you to the runway. SOme approaches fly a loop first, others go straight in.

THe flightpath (left-right) is done by the GPS-Autpilot combo.

But you manage the altitude yourself.

A normal ILS glideslope descends 300ft per nautical mile.

So you have to manually make sure you are at

3000ft at 10Nm

2700ft at 9NM out

2400 at 8 NM out,

etc.

You can do that usin the altitude and descent rate on the autopilot. Or manually descending.

Then at 1Nm to 2Nm distance you disconnect autopilot and autothrottle and land.

If you want to do an ILS landing.

You can use a GPS plan to get near the airport.

Then about 30-20Nm away, swithc GPS/Nav to Nav mode

and fly to the start of the straight in aproach manually. By selecting the correct heading in the autopilot.

Then engage ILS approach about 10-15 NM out.

I you create a IFR flightplan, and use ATC, ATC will guide you through all these steps.

It wil guide you while you follow the flightplan.

It will tell you Vectors (headings) to the Active runway. You switch GPS/Nav to Nav mode and follow their instructions to fly to the start of the straight in aproach. Again by manually by selecting the correct heading in the autopilot.

Then engage ILS approach about 10-15 NM out.