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scott967

Need a favor: ILS test, KOMA

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Guest CWD

I need someone to do me a favor.Try to fly an ILS approach for runway 32L at Eppley airport, Omaha, Nebraska (KOMA).I just tried twice, once on autopilot and once hand-flying. On autopilot, the aircraft hurled itself into a frantic climb as soon as it was switched to approach mode, even though the flight director showed the glidescope was, if anything, slightly below my altitude.Attributing this to a misuse of the autopilot on my part in the unfamiliar plane I was flying, I tried hand-flying the approach. Keeping the needles perfectly centered leads me directly into the unforgiving earth at least a mile short of the runway threshold and thirty degrees or more off the runway heading.It's a documented fact there are some ILS's in default FS9 that will do their darndest to kill you. One of them at my local airport, KCMH, for example, will cause you to land on the roof of the terminal building. I want to know if this is one of those cases or if I'm just really, really screwing up badly because I don't fly many ILS approaches.Thanks in advance for anyone who has the time on their hands to take up the challenge.

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I have done this in the past at KOMA with no problems with the glideslope. I checked the default AFCAD and the placement of the GPS and angle at 3.0 degrees appear correct.Is this a default aircraft? If not, try it with that to take any gauge weirdness out of the picture.Also insure you've got the correct localizer tuned in by using audio ident or display on your nav display if available.

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I'm using the default airport with UTUSA and FSG 38m mesh, which shouldn't impact the ILS behaviour. I selected the default boeing 734Flew to alt 3500 @210 kts flap 5. selected ILS 32L approach with RIKKY transition on the GPS. Selected Autopilot with alt hold @3500, in GPS mode with NAV selected. This approach has a procedure turn. The GPS flew me over RIKKY and started outbound to the procedure turn (point CF32L). Flew the procedure turn. AP didn't follow that closely and overflew the return leg (319 mag) but was back on desired track by the time I was back to CF32L. Selected alt 2800 at -500fpm opn the MCP and reached 2800 ft prior to RIKKY. By RIKKY was pretty close to track. As I settled with the LOC aligned, I switched from GPS to NAV and continued the approach using the LOC. Slowed to 155 and selected flaps 30 / gear down on sked. On landing config as GS reached 1 dot. Selected APP mode on MCP at GS 1/2 dot and captured GS. Flew with coupled AP in APP until 100 ft above threshold then canx AP and it dropped right on the numbers.Try this and see if you get the same results. I had fuel 20%/0%/20% at start of the test with default station loading.scott s..

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Your issue at KCMH is probably the default back course issue.Both runways are setup the same way - 10L/28R use 109.10 and 10R/28L use 108.70. Since all four localizers have backcourse enabled - your instruments are receiving two conflicting localizer signals on the same frequency on approach to any runway.Deselect "Enable Back Course" on each of the four localizer properties - then save your AFCAD - try again.And as noted - always try approaches with (1) a default aircraft with default gauges, and (2) real world charts in hand for the approach. You will usually find the issue is your aircraft / gauges, not the airport.Be very wary of AFCAD files which "fix the location of the ILS / localizer" like the folks who move the KASE localizer. Those usually only work for the one aircraft the author flies. But do remember the Navaid data in FS2004 is for the fall of 2002 - so some newer changes will not be in the system.

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Guest CWD

OK, at least now I know it was me or the plane. For the record, I did indeed have the real-world chart in hand.

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Guest CWD

Just tried it in an aircraft I trust (my faithful PMDG 1900C) and it worked as advertised. Back to the books...

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Which is why I always recommend checking the localizer ID. For those who have not modified the AFCAD for shared frequency opposite end localizer and GS (if present) the correct one should appear when near the centerline of the LOC as you are still on the merge heading. My experience has been that at KMSP.So as Reggie states if you use an airport with shared frequency localizer/GS quite a bit then modify the AFCAD to dump the back course. If you are going to a new one (or any one actually) check aurally with your audio panel on nav the Morse Code ID or if your aircraft has an ID character display on various gauges, stay on heading and altitude until the proper transmitters are identified. Then use HDG to turn inbound and engage LOC or APP for an AP coupled approach.

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Guest CWD

>Which is why I always recommend checking the localizer ID.>For those who have not modified the AFCAD for shared frequency>opposite end localizer and GS (if present) the correct one>should appear when near the centerline of the LOC as you are>still on the merge heading. My experience has been that at>KMSP.>>So as Reggie states if you use an airport with shared>frequency localizer/GS quite a bit then modify the AFCAD to>dump the back course. If you are going to a new one (or any>one actually) check aurally with your audio panel on nav the>Morse Code ID or if your aircraft has an ID character display>on various gauges, stay on heading and altitude until the>proper transmitters are identified. Then use HDG to turn>inbound and engage LOC or APP for an AP coupled approach.>>There's no problem with the ILS itself I've concluded, it pulls the little 1900C down perfectly. However, when I try to intercept the localizer in the iFDG MD-11 with Alain Capt's panel, the plane inexplicably begins a rapid climb and turn to the right. Last time I just let it keep going to see what it did. I was past 10,000 feet and still circling when I gave up.

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That sounds like classic NAV/GPS switch in the GPS position behavior.I assume you have not had problems with this aircraft at other airports in the past.Have you recently installed any aircraft / panels since you last used the aircraft successfully?The switch (gauge) might have been overwritten by one which is reversed. It's happened to me a couple times.

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Guest CWD

>That sounds like classic NAV/GPS switch in the GPS position>behavior.>>I assume you have not had problems with this aircraft at other>airports in the past.>>Have you recently installed any aircraft / panels since you>last used the aircraft successfully?>>The switch (gauge) might have been overwritten by one which is>reversed. It's happened to me a couple times.This was my very first flight ever in the aircraft. I'll try once more and make sure the Nav/GPS switch didn't get hit.

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Guest CWD

OK, it was definitely the NAV/GPS switch causing the problem. I made sure it was on NAV and this time......well, this time the plane at least figured out the runway heading, though it still yo-yoed wildly above and below the glidescope until finally pancaking in the middle of what was undoubtly a city park. I would feel silly if I wasn't busy feeling frustrated.

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I have that panel, but never really used it. Gave it a try and agree that it is a little sensitive in how it will caopture glide slope. I suspect with some practice the secrets could be pulled out of it.scott s..

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