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PMDG 747 FLCH, ATC software

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Hi,I have a question here, when I start the descent at 10.000ft, I always selected the approach page and select the speed marked in flaps 25

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Hi Victor, excuse the wordy reply! :-)I'll answer your second question first as it's an easy one. Check out 'Radar Contact v4.0', outstanding ATC service modelled to FAA standards, well worth the money trust me! http://www.jdtllc.com/Back to question one: There's really no need to slow down that far so early. What AP mode you use I'll cover in a moment, but the speed from the FMC next to that flap 25 config is your reference speed for the approach itself.Prior to establishing yourself on the approach a higher speed is fine, and in fact usually a better option as it keeps you aerodynamically 'clean' for longer, reduces your noise footprint and (I imagine) helps to manage fuel consumption.What I normally do is manage my speed on the basis of flap settings. The key thing is that you want to be extending flaps to 20 and lowering the gear as you intercept the glideslope. This normally requires a speed of about 160 knots. Once on the approach you reduce the speed to Vref and lower the remaining flaps so that the aircraft is stable at about 1,500 feet.SO, working backwards from the 160 knots as you intercept, I aim for 180 prior to LOC capture, so my pattern speed (normally below 5,000 feet ) is 220 knots. I normally start slowing from 250 to 220 knots at about 6,000 feet above field height.Hopefully one of our real-world 744 drivers such as Cowpatz or Jon B can step in to offer their advice (Oi Steve! Howzit?!), but the above speeds work for me at home! If they do, follow their advice without doubt as it is definitely more reliable than mine. ;-)Back to the matter of ATC, if you DO get radar contact, you'll be pleased to know that it issues you 'not below xxx knots' speed limitations in the approach area anyway, so the above may not apply, just do as ATC instructs!Lastly, autopilot modes: FLCH controls speed using pitch so it is excellent for the climb as it avoids the unpleasant chance of setting too high a vertical speed and thus slowing the aircraft down too much.To illustrate my point, in the climb set a V/S of 6,000 FPM and watch what happens! :-)However, for the descent I personally use V/S as I can then manage my descent so that I arrive at a certain waypoint at a certain height.Hope the above helps and doesn't confuse you. Please post again on this thread if you need more help, I or others will happily assist you. :-)CheersMark

Mark Adeane - NZWN

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