I like to fly ILS approaches with the C172 or TBM930 but I wonder what the correct ‘trigger/time’ is to switch from GPS to LOC 1 and activate the APPR-button.
Is there an indication on the cockpit panels or do you need to get that kind of information from an airport information chart?
I do it once I’m on the loc intercept course, which works well.
But don’t know if its correct accdrding to procedures
I’ve been activating mine on the Initial Approach Fix, which I’m finding is generally at a transition. This gives more than enough time to get established.
Ideally you’d do it when configured (flaps, speed) and stable on the ILS, for stable the ILS height indicator should be above your current height. You should also be established in the ILS arch. That should be plenty for flight sim. Just manage approach speed for your aircraft and be ready to take over before the threshold and land as normal.
If visual and comfortable on the ILS just fly it in by hand using the PAPI lights.
It’s a judgement call, and depends from situation to situation.
In an ideal world, the perfect time to switch from GPS navigation to NAV1 is once you’re vectored off the GPS route, and at the latest once you’re on the localizer intercept heading.
As for when to arm the glideslope intercept, don’t arm it until the glideslope signal is received.
One thing I want to stress though is that this is a detail that depends from pilot to pilot. Good airmanship is that you do something as soon as you reasonably can, but everyone has a slightly different flow in a real plane, and what matters more is consistency. Of course, unless there’s a company SOP that dictates otherwise, then obviously you’re bound to the SOP.
A friend works for a local airline (he’s an Airbus pilot) and told me they usually activate APPR right before the final. I’ve seen other pilots on YT doing the same.
Watch the vertical ILS diamond. When it hits the centre marker (when I activate) I can’t see the point of using approach hold personally (especially until the live weather gets sorted). Manual landings my favourite part!
I just use the ILS to get me lined up… Then hand fly it following the GS indicator when it comes alive (starts dropping). Unless visibility dictates that’s not possible…
In the real world you would arm the approach (APR) on the autopilot prior to reaching the final approach fix (FAF) . You’re flying with heading or Nav mode engaged, APR armed, when the aircraft enters the lobes of the ILS transmitter (intercepts the localiser beam) it should capture the localiser and turn on to the final approach course. As you approach the FAF you will see the glideslope indicator start to move down from the top of the display, as you are intercepting the glideslope from below.
At the FAF the GS indicator will remain centered on the display and the aircraft should descend on the glideslope.
You control speed with throttle, do your final landing checks and then as you approach your minimum altitude/height you’re glancing out for your visual runway in sight cues. If you do not have the required visual cues at your decision height then you carry out the missed approach procedure and try again. If you can see the runway, you disengage the approach and land.