I am having a problem with the glide slope when landing with the ILS.....It's responding laterally but not vertically,and will not turn off the altitude hold button automatically like it should. It's strange because sometimes it works perfectly.Any help will be most appreciated.

I am having a problem with the glide slope when landing with the ILS.....It's responding laterally but not vertically,and will not turn off the altitude hold button automatically like it should. It's strange because sometimes it works perfectly.Any help will be most appreciated.

Are you clicking on the APR button when the glide slope indicator begins dropping? If you are still having trouble, I suggest reading the following articlehttp://www.stoenworks.com/Tutorials/Flying...%20coupled.html

I am having a problem with the glide slope when landing with the ILS.....It's responding laterally but not vertically,and will not turn off the altitude hold button automatically like it should. It's strange because sometimes it works perfectly.Any help will be most appreciated.

You also have to switch from "GPS" mode to "Nav" mode. Sometimes, when I forget this, I have related problems.Harry

You also have to be below the glide slope before you hit the APP button. One exception I've noticed is the PMDG MD 11 which seems to capture glide slope when APPR/LAND is engaged from above it.

Thank you for your replies.Yes I'm below the glide slope,I switch GPS to NAV and as far as I know everything is as it should be. As it works sometimes I thought there may be a bad file or something. One more possible clue, if I manually disengage the altitude hold button the aircraft very rapidly heads for terra firma. :(

Also.. make sure you aren't too heavy.. and that you're at a reasonable approach speed..

One more possible clue, if I manually disengage the altitude hold button the aircraft very rapidly heads for terra firma. :(

Most likely pilot error. You as a pilot have to control the aircraft so it doesn't head for terra firma. Either fly it manually or control its speed/throttle and autopilot mode so you have full control over the events.

At the risk of ratating th obvious, are you sure you are using a ILS approach and not a LOC only approach?

Also, which aircraft are you experiencing the problem in (which airport, and which runway ... so we can check to make sure there is not a bug on that runway or that it's not an ILS).

You may not fly like I do so this may not apply - here is what I do. It works every time unless there is a problem with the ILS in AFCAD.Before you fly, write down all of the ILS frequencies for you destination from AFCAD. Since there are many different add on's out there, AFCAD seems to be the most reliable source for the proper frequencies.I start my decent following the GPS flight plan according to ATC's instructions. Eventually they will start giving you headings. Follow their instructions. When they give you your runway, enter the frequency in to the NAV1 radio and choose the approach for that runway in the GPS and hit activate. Remember, you are still in heading mode so you won't actually start flying the GPS approach yet.Continue to follow ATC's instructions until about 20 miles out when ATC gives you instructions that are something like - "you are now 20 miles away, Descend to XXXXft (final alt to intercept ILS), turn XX degrees and contact XXXX tower." Follow the hand-off and altitude instructions but don't follow heading instructions, just switch back to GPS and it will line you up with the runway. Once you are lined up, deactivate GPS mode, NAV and yaw damper. Activate APPR. At this point you should only have ALT hold, APPR and AT activated. Slow down and drop flaps and gear according to the chart. Kill AP at 200ft. You should eventually intercept the ILS using this method. Just watch the indicator on the PFD to make sure you don't overshoot the ILS. Is this a real world procedure? No - it works for me and it wouldn't apply to most of the complex aircraft out there. If you are navigating with the GPS, this is they sure fire way to make sure you intercept the ILS.BTW, if this is the method you choose, practice it at airports with relatively flat terrain. ATC has a habit of fling you in to mountains.

Thanks Jeff, I printed your post and used it as you suggested. It seems to have fixed the problem. Thanks again. :(