solved Cannot acquire ILS

[esa1178]

Hello

I have been following a video tutorial regarding the ILS procedure.

At the correct altitude when turning to line up, runway heading set twice. ILS freq set twice.

Speed at 160, APP engaged, CMD B engaged...

But aircraft remains at the last set altitude/heading.

Does not acquire the ILS.

 

Thanks for your  help in advance

 

Mark Harris

ESA1178 

Edited March 1, 2018 by Morten

[Morten]

ILS frq set on Nav 1 or 2?

 

[Litjan]

Hi, can you show a short video or some screenshots that illustrate what is going on?

Thanks, Jan

[esa1178]

Destination EHAM ILS 06. NAV1 & NAV2 set to 110.55

Here are pics.

As you can see the aircraft remains at 2000' way above the glide-slope...

Edited July 13, 2017 by esa1178

[mfor]

Well if you look at the top of the EADI display, you can see that the AP is in ALT HLD mode (green, top) and G/S capture is armed (white, below), so it is waiting for the plane to cross the glideslope. So  maybe you were already above the glideslope when you armed APP and never crossed it thus the AP never captured it.

IOW you need to cross the glideslope with APP armed for the AP to enter G/S mode and land. In that case the G/S will move to the top in a green font and the AP will disregard any altitude setting in the MCP.

If you did cross the glideslope, then disregard this post.

Edited July 13, 2017 by mfor

[Morten]

And always cature the GS from below..

[echodelta]

Mark, i can confirm that APP mode does capture the G/S correctly, as long as its armed before the glideslope needle is in the middle. (above middle=below glideslope... below middle=above glideslope)

try this to rule out a few errors: fly your usual route..but reduce your altitude earlier than usual once you reach T/D. then enable LOC just as you've lined up for approach to the runway. once LOC has been locked, keep an eye closely on vertical needle.

if you're below the G/S, the pink diamond needle will be right at the top and slowly move lower down as you get closer to the runway, just as you get close to the mid point, hit APP mode and enable CMD B. you'll then notice the G/S in white letters turn green then you should be good after that.

[clif737]

All my glidescope problems were my fault so far. Too high is usually the issue. 

[Litjan]

the glideslope will capture at 2/5th dot deviation - no matter if you are above or below. You CAN actually capture the glideslope coming from above, it´s just pretty hard because the airplane needs to descend fairly steep to capture it.

The other prerequisites are "LOC captured" and heading within 110 degrees (or so) of inbound course (so you don´t capture an erroneous glideslope by accident on a backcourse loc approach).

Jan