Glideslope lock-on in Autopilot

[Gringo6]

In F/S 2k2 - When the autopilot is engaged in the approach hold mode, the Cessna airplanes will lock-onto and hold both the localizer and the glide slope, while the other airplanes will only lock onto and hold the localizer, but not the glide slope.

What changes can I make to get these other airplanes to also lock onto and hold the glide slope ?

Thanks,

Gringo

[WebbPA]

I think the problem is with your piloting, not your aircraft.

As long as you approach the glideslope from beneath it you should not encounter these problems.

[Gringo6]

Dear Webb:  Thanks for your response. While I disagree with your premise that it is the piloting, since the same pilot and technique are used for all efforts, I am greatly encouraged by your text since it seems to infer that the other aiplanes SHOULD lock onto the glide slope and that was my real question - should they work like the Cessnas and your message confirms that they should.

Now if I can just figure out why they don't!

Thanks again for your response.

[WebbPA]

Try this in a default jet.  The Learjet would be good.

Take off and ascend to 3000 feet.  Go about 30 miles and, if you have tuned your radios in advance you can see the GS indicator creep up.  After 30 miles turn 180 degrees back to where you came from.   Lock in your course and NAV radio (if you haven't already done so).

The glideslope indicator, if in range, should still  be above you.

Hit your APR HOLD button.

The autopilot shoul maintain 3000 feet until you hit the glideslope, then start a descent just like the Cessnas do.

Edited because the first response was completely screwed up.  I just flew this course and realized how screwed up the unedited post was.

[monkeyboy726]

lately i've been having the same problem with the autopilot glideslope intercept. i didn't have this problem before and i haven't been doing anything different.

anyways..today i was approaching 28R at SFO in default 777-300. i hit APR HOLD well outside the outer marker.. like 14-15 miles DME. i intercepted the localizer just fine.. but after setting final flaps and gear down about 10 miles out...i noticed the glideslope was not being intercepted. i looked around and found the APR HOLD button off! i don't remeber turning it off... maybe its just a glitch?

[Saratoga]

In a perfect sim, you fly and line up below the glidescope on the localizer. Then you hit your APR button and it SHOULD fly straight and level along the localizer and when you are one dot below the glidescope, the alt hold should disengage and the autopilot should find and hold the glidescope. Keep in mind that you should not do anything major (i.e. extend lots of flaps or the landing gear) while it is intercepting as it messes up it's intercept course. I suggest that if available, you use the autopilot to do everything possible as it is much easier on it if it is controlling everything about the plane including speed.

[Gringo6]

Thanks for all the responses. I can see that others are having the same problem that I am having.

I go out about 10 - 15 miles from the airport, engage altitude hold, and approach hold , come up under the glide slope and when the altitude is about the same as the glide slope the altitude hold disengages, but then I get a really strong down pitch command. I mean it is strong, as it takes full up elevator and full up trim to keep the aircraft from diving into the ground.

Now I can do the same thing, except instead of approach hold, use the CNTL+O (localizer hold) command and about the same thing happens except that the airplane is manually controllable in pitch and doesn't have the diving tendancy.

On the few airports where the runway has a localizer on both ends that are on different frequencies I can also tune to the other end frequency and use the backcourse hold and achieve the same result.

I have tried "uninstalling and reinstalling " F/S 2K2 several times and the outcome is always the same.

No Joy ! !