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Guest sacem

PMDG GS problem

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Guest sacem

Hello,I discovered that after I upgrade the PMDG 747-400 by the Universal Update Package, when I approaching the ILS runway I found something strange...... Did the PMDG 747-400 can recognize the rwyway is ILS CATII or CATIII ?? Because I have tried 3 different rwys and all of them are CATII ...... when I reach around 200ft near the minimum DH, I heard the sound "Guide Slope....Guide Slope" Actually this does not affect my landing because I turn off the autoland before the DH, but how about when I land on a CATIII rwy ? Is this only a bug ? Just a fake guide slope warning sound ? Will the plane still can auto touch down ?Jacky Yeung

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Guest 744nut

Hi jacky,Cat II and III is (as far as I know) not detected by equipement in the AC. Crew and aircraft need to be qualified to do a landing under certain visibility conditions. The GS...GS is called out probably due to some movement of the aircraft (turb/wind) on the Glideslope.regardsTon

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Guest D17S

Interestingly, GS's job is to get the airplane over the arrival runway's threshold at 50 feet. Then it simply stops. It just drops you off, in mid-air. Next time watch very carefully. PMDG has this modeled. If you watch carefully, GS goes off scale once you are over the threshold. From there, you are not using GS for vertical guidance. Flare will engage shortly and it's all radio altimeters, aerodynamics and the theory that "an object in motion will tend to remain in motion.

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Sam... even before the G/S transmitter (on the ground) is flown past, throughout the approach, the aircraft doesn't rely solely on G/S signals. The A/P builds up a mental image of the glidepath and you can lose G/S signals or the signals can be deflected to abnormal positions by traffic (in front of you) for a few seconds, but the aircraft will not suddenly do crazy things or fall out of the sky. However, if the G/S signals are lost or are abnormal for a lengthier time period, then you will get cautions.Cheers.Q>

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Guest D17S

Interesting. Which box has the job? And as far as you know, is this a recent assignment? BTW, I see that the -400s did away with the inboard ADPs. What do you guys call the new electic hydraulic pumps? Only a year left. Gotta start getting up to speed.

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The Flight Control Computers have this job, Sam. It's nothing new. 767's also have this feature.The #2 and #3 ADP's weren't disposed of.... It's a real world option on the 744. I've seen these on 744's with P&W engines... perhaps because the engine reversers require hydraulics (extra demand).Cheers.Q>

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Guest D17S

Then it's probably my old 747-1/200s that do the flying rock trick. (Oh stop! Yes there are some that can manage a cat3!) We're getting our normal collage of whatever they stumble across. Some new, some not. So I'll most likely see it both ways. Nuts. Was hoping to get rid of at least 2 of those noisy buggers.

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