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JSACKS

One last autoland question....

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Is it necessary to explicitly hit the second autopilot to ON to achieve autoland? I hit the second AP button at 1500 AGL just to be sure but I wasn't sure if it's actually necessary or whether the system self checks and auto-arms both channels if all's well passing 1500' AGL.Appreciate clarification, thanks!Jonathan

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Only necessary if you want the plane to flare (and idle during flare). If you don't enable, you'll need to disengage a/p and flare by yourself.Nick B.Continental Airlines Virtual 737NG Pilothttp://www.precisionmanuals.com/images/forum/800driver.jpg--AMD Athlon XP 3200+ @ 2.2 Ghz (Equal to 2.8 ghz)400W Power supply3x 80 mm Case FansSoyo VIA KT600 Dragon PlusnVidia GeForce FX 5200 128 mb2 x 512 PC400100 GB Western DigitalMicrosoft Sidewinder Precision 2

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The real airplane does NOT auto-arm the second autopilot - the pilot must actually press both CMD buttons before 1500ft RA for the full autoland to function.

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Single Channel STILL performs this check just like the real one does. But as Ryan said you must arm the second A/P prior to 800 RA. Once APP is active one CANNOT push the button to de-select the mode. And let me be very clear about the single channel AL. On the real aircraft it WILL AUTOLAND AND FLARE in SINGLE CHANNEL but will not have the bias trim which could mean a very hard harding and worse. The flare could be early or late or even cause a stall, not to mention one could not try it on the real aircraft under any circumstances ;-). Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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You know, this plane is so great to hand fly I haven't even tried the autoland yet, and I've owned her since day 1 (or maybe 2). With all this talk I think I need to give it a whirl.Question: Does the autoland provide rudder inputs during the flare to counteract the crab angle resulting from a crosswind?Thanks!BTW, Randy, it's nice to see you back around the forums again.Edited for hangover induced typos... boo!

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Gentlemen:Once again, a hearty Thank You for such timely and excellent advice.Once I am confident I've got autoland down pat, I'll be doing hand-flying to touchdown practice and hope that will go just as well.Time to take off (but by minivan this time!) with family for Shenandoah now. The PMDG manuals will be bedtime reading. Back in a week.Cheers!Jonathan

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"On the real aircraft it WILL AUTOLAND AND FLARE in SINGLE CHANNEL but will not have the bias trim which could mean a very hard harding and worse. The flare could be early or late or even cause a stall,.."My understanding of bias trim is that if the A/P completely trips off completely for some reason late in the approach, the elevator will return to it's neutral point (with the A/P disengaged) and the (nose up) bias (stab) trim will give the aiplane a nose-up attitude, rather than a 700'/min crunch into the runway (or a reasonable attitude should the pilots decide to do a go-around). With bias trim, if the A/P does trip off at more than the normal flare height, it will flare early BECAUSE of bias trim....and if there is no throttle input (automatic or otherwise) bias trim may cause a stall.Bias trim is also present on the 767 and 747-400 in LAND2. Single A/P landings do not have a flare (unlike the NG), so it is necessary to add bias trim just in case flare in LAND 2 becomes crunch in "NO AUTOLAND" if the A/P drops out.Hope this makes sense.Cheers.Ian.

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