How to use the autopilot for approaches using ILS?
From FlightSim
Q:
I'm having trouble locking on to the ILS, have tried a few places mainly Manchester & Liverpool. I approach the ILS at about 3000 ft 10 miles out I change from the GPS to nav 1 then press the approach hold . Do I have to disengage the altimeter & nav or should it lock on to the ILS when I press the approach hold?
A:
Here's what I do, not saying in any way that it's the correct way, or the
best way:
This is in a B-777 or a B-737...
- Slow to 220 kts IAS, get lined up with the ILS runway about 50 miles out, at about 7000 ft AGL. Tune Nav 1 to ILS loc freq.
- Continue on rwy heading lined up as close dead-on to runway as possible. Use the map to keep lined up as perfect as you can.
- By the time you are 25 miles out, you should have picked up the localizer and GS. The instant you start copying it, hit the APP switch. You must be below the GS to fly "into it", when you get level with it, you will slide right down it. If you are above it, you have a problem. If you are not too far above it, you can do a rapid decent and hit it. But if you're too high, you may have to do a missed approached and try again. If you are left or right of the localizer, you will have to fly left or right to center up. Then just let the autopilot fly you right down to the runway. On the way down, gradually decrease your speed about 10 mph every so often, add in a notch of flaps to keep the nose down, and experiment to see what works. I tend to want everything automated, while other guys, in fact most guys, don't. So whatever works for you...Enjoy. I know one thing...pressing approach hold does NOTHING until you are actually copying the ILS localizer, so don't bother until you are copying it. Then when you are copying it, and you punch approach hold, it takes over everything. Once you've learned how to intercept the approach, practice other approaches besides straight in from 30 miles out.
