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Guest RRF985

Both autopilots for autoland?

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Ok I know that in real life you need both autopilots on to let the airplane do autoland. I however can only get 1 autopilot on at a time. Whenever I try turning both on I get a FMC message about runing the radios. I have NAV 1 with the ILS frequency. Other times if I have 1 autopilot on and I try and turn on the other it will simply switch to the other autopilot.Is there a secret to getting both to turn on?-Ryan

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Yes, if both ILS freq are tuned in you can activate both autopilots, but otherwise it'll just switch. What is the exact message from the FMC?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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To expand on the post above, you need to have the ILS freq in both the NAV1 and NAV2 recievers for the ILS dual coupled approach to be active. Otherwise, like mentioned, pressing the other a/p button does nothing more than switch the active a/p.

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Hi Ryan,To perform an Autoland you are completely correct in that you must have both AFDS systems engaged. Even when you meet all the criteria the 2nd AP will not engage until the systems have carried out their own Deviation Alerter check which occurs at 1500' RA and you can see this happen with the LOC/GS deviation scales flashing amber for 2 seconds (This amber flashing is actually what you get when you are outside set tolerances for LOC or GS tracking). This check occurs on all ILS approaches and is not related to the number of AP's engaged. However it is only after passing this check that the second AP will actually engage and you will see 'CMD' in green replace the amber 'SINGLE CH'Autoland Criteria:1. Valid ILS frequency selected in both NAV boxes and a valid signal being recieved.2. Must have captured the LOC3. Have both NAVs passed the Deviation Alerter check at 1500'RAIn the Geezer Gudie Ver5 there is a step by step procedure to carry out an Autoland. This procedure is generic and will work at any airport where you have suitable ground aids (ILS)Hope this helps,

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Ok thank you guys so much. I didn't realize the ILS frequency had to be set in both NAV radios. Everything else I was doing was fine. Thanks again!!!:D -Ryan

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