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victorlima01

Problems with dual channel autoland

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Hey all,I'm having a problem regarding my autolands and it started oinly recently after I reinstalled FS9.Basically, after setting up the aircraft for autoland by tuning both nav radios to the ILS frequency and arming the approach mode via MCP and selecting both autopilots ON, I still get on my annunciator the yellow SINGLE CHANNEL annunciation, even though the autopilot follows the ILS down to the runway and flares flawlessly. Could it be a problem with the gauge (my PFD that is)?Thanks in advance for the help,Victorhttp://www.precisionmanuals.com/images/forum/800driver.jpg


Cheers,
Victor M. Lima
 

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Guest aarskringspier

If I am not mistaken, not all airports support the dual channel autoland? I believe I get a single every so often.

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Guest GeoffC

Victor,To answer Randy's point about Airport support for autoland, just try EGCC in the UK as it definately works, although personally I haven't encountered any that don't.I think your problem may be altitude related. As a test try approaching the airfield from 12 miles out at 2500' with APP armed have captured the LOC. This will allow you to hit the glideslop at altitude and commence descent. As soon as the G/S arms engage the second AP. It should pretty much land from here if the speed, flaps, and gear are set correctly.I think you may be getting too low before engaging the second AP in which case it's locked out. I thought this happened at anything below 1500' but a reference manual suggested the following:At 800 Feet Radio Altitude the second autopilot must be engaged in COMMAND by this point. If the second autopilot has not been engaged by 800 feet, it is locked out. If you still have a problem a more detailed report will be required including airport, alt, speed, configuration of aircraft etc etc.

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Guest

Had it fail at SMJP yesterday when I came in too high.Also at EDDM saturday I think it was when I was right on target.Might have to do with the exact timing when you engage it?

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Guest tomahawk_pa38

I also have a related problem which I put in a different thread with no real results. Just lately I flew EGGD - to LEPA and then EGGW - LEMH, perfect flights but as I turned onto finals in both cases I got the 'Nav Invalid' message. Tried to retune the Nave radios but both were frozen, so I landed manually.Reset the flight and returned to Luton - same thing. I reset the ILS frequencies on both radios as soon as I left LEMH just in case. At some stage in the flight, the radios froze again and although they showed the right frequencies, the ILS didn't show on the gauges. Again I was unable to retune the radios.I double checked all of the frequencies - all correct. It only seems to happen when I leave the UK, flights to and from EGPF to London and Bristol are unaffected. I think its only happened since I installed Simwings 'Balearics' scenery. I'm fairly sure that all of the other parameters for an autoland are Ok - I'm at the right height to intercept the glideslope and I'm within limts for capturing the localiser, both a/p light up and the App button light illuminates. Can anyone help please ?

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Guest GeoffC

Try my suggested scenario and see if it works. I've never found it difficult to capture.

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Guest

at MSJP I did get a message that the ILS course was incorrect, despite setting the course from my charts...

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Guest Zapper

May I have a screenshot or two pls.Failing that tell me what teh FMAs are saying as that will ALWAYS tell you if it is going to work.IRL, if an airport has an ILS then the 737 WILL fly an Autoland to it as the AFDS only wants a valid ILS signal and doesn't care whether the airport, the aeroplane or you are actually certified to do one :DLMK how you get on. in fact please use my tutorial at your favourite airport and LMK the results.Happy Landings,

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Guest aarskringspier

this is what I get every time until about 1500 feet. Then the glide scope indicators flash and locks CMD. Seems to happen every time I have tried it.finallarge6ew.jpg

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Guest captbulldog 2

SINGLE CH is NOT a warning! It is an indication that the plane is flying in SINGLE CH mode which is standard procedue at that point. At 1500 RA The GS and LOC will flash as a SELF TEST and if all ok the plane will proceed in DUAL CH.

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Looks good to me.At 1500ft you should get the yeloow flashing for the A/P confidence test and then the DUAL CH should kick in. It's all normal.BTW. WHat scenery are you using? It looks neat!Hope it helps,


Mats Johansson
PMDG Flight Test Dept
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| Asus Z270-A | Intel i5-7600K @ 4.8 GHz OC/H2O | nVidia Geforce GTX 1070 8GB OC/O2|

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Guest aarskringspier

All I have for scenery add ons is:Project Blue Spherefs9wateraeu7apt_liteI havent decided what to do about scenery yet, if I wanted in payware. I know I would like the Mega Scenery DFW but thats about it.

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Guest hlm65

Hi,if you don't want to get a RW/APP CRS ERROR msg in the FMC, you mus set in the CRS window of the MCP the CRS value seen in the INIT REF page when you have selected the approach.

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Guest

Tried it again last night on approach to LEMD 36R.Engaged VOR/LOC when receiving the localiser. At about 4000" ASL (2000" or so AGL) GS came alive and engaged APP and AP channel B.Single CH came on and didn't go off.

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Guest aarskringspier

Hmmm I dont know, I have never had it not go off. Every time it doies its test at 1500, flashes and then locks command.

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