Pilots often have difficulty maintaining the localizer on ILS (or GPS-LPV) approaches:
“I’m always chasing the localizer needle and get so frustrated that I forget to maintain the glideslope needle; then I have to miss the approach.”
In my experience, this common problem most often occurs when pilots make excessive heading changes, rather than because the wind has changed. These pointers should help:
1. Join the final approach course far enough out to allow time to nail down your wind-corrected heading before joining the glideslope. Ask ATC to put you on the final approach course a mile or two outside the final approach fix. That will reduce your workload.
2. Commit to memory the heading you’ve identified to fly, and return to that heading whenever you drift off. Say you’ve determined that, with wind correction, you need 360 degrees inbound heading to stay on the localizer. Now MEMORIZE that 360 heading, AND RETURN TO IT EVERY TIME YOU DRIFT OFF HEADING. If you look away for a moment, your heading has likely changed. If your heading is not exactly 360 when you look back, turn immediately back to 360, level wings, and THEN check the localizer needle to see what it’s doing. This will stabilize your heading on the approach.
3. Limit final approach course heading corrections to 5º at a time. (You’re probably used to using 10° corrections or more to track VOR or enroute GPS.) If you do need to correct the heading, MEMORIZE the new one. So if you’re inbound on that 360° heading and notice the localizer needle drifting to the left, make a CONSCIOUS HEADING ADJUSTMENT of five degrees left (355º), turn to it, and memorize it. Again, if you drift off that heading turn immediately back to 355° before making any other corrections.
4. Make all localizer or LPV heading corrections using ½ standard rate turn. (That’ll reduce the “chasing.”)
5. Throughout the approach, continually reset the heading bug on your heading indicator to mark the heading you want to fly. If you have no heading bug, consider installing an add-on bug, or an indicator that has one. A heading bug helps tremendously in keeping you pointed where you want to go using minimal brainpower.
All this may sound elementary, but it’s not. Most pilots are busy enough on precision approaches that they chase the needle rather than consciously selecting, remembering, and holding a heading. But stabilizing your heading anywhere near the correct one prevents the needle from drifting much, so it’s easier to correct. That’s why it’s more effective to hold a heading (and return immediately to it if you drift off) than to chase the needle without a specific heading in mind.
Obviously, it’s hard to absorb this sort of thing from reading. But try these tips when you next practice precision approaches, and I think you’ll be pleased with the improvement. (See also my post, “IFR made easier…“)
©2009, 2014 Gregory N. Brown