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Joe L

AT / Autoland ?s

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Ok, more questions.What is proper technique for taking over an ILS approach on short final? Should both AT and A/P be disconnected? In many other Boeing sims (not 757 though) one can cancel a AT mode but leave the AT armed for go-arounds. As I understand proper procedure, AT cannot be in SPD mode at landing unless in AUTOLAND. Once any mode is selected in AT you can not go back to just an "ARMED" AT mode. Even cycling on and off results in the last mode at disconnecting coming back is soon as AT is switched back on. I do not find any details in the manual.Secondly, why does AUTOLAND automatically arm and come on along with all three A/Ps? ESPECIALLY when NAV2 is not even tuned to the ILS (manually set to another freq). I find this quirk irritating since there are few airfields with CAT-III approaches, so AUTOLAND wouldn't be used much, I believe. I am just going to disconnect on short final 95% of the time anyways, but seems as if we should be able to select it by lighting all three A/Ps, not have it happen by itselfAnd as a criticism - irritating about no NAV2 - having the copilot's MCP side set as a NAV1 duplicate sounds as if someone was in a hurry. Yes I know how I can tune NAV2, but, just not right that it is not where it should be on the copilots side. I can understand if it was VC only, but not at all?Still enjoying the release though. THX.Joe Lorenc

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JOe,Your question about proper ops of the A/T has bothered me, too.There is a NAV2, you just have to be in the VC to dial it manually. You can also use the NAV RADIO (press "NAV RAD") page to enter the frequency and OBS setting once you've pressed the AUTO/MANUAL button on the MCP. It works like a champ, and since I'm flying singlehandedly, I make it a point to dial up both NAV1 and NAV2 to the ILS frequency when setting up my approach.

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Where in the VC is NAV2?In mine the Copilot Nav on the MCP is also NAV1. (Even the Tool tip says so). Any change there change the pilots side also for me. I do realize you can change it in the CDU.Thx,Joe Lorenc

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NAV boxes- I'm afraid it is a problem with the modeling of the avionics in the 757. On the real aircraft there is a seperate radio tuning box on the pedestal for ILS tuning. It's one box that tunes 3 receivers.It can be seen in this link just above the rudder trim dial http://www.airliners.net/open.file/1004494/L/The NAV tuning boxes cannot be tuned to ILS frequencies on the real aircraft. Regarding autoland - once approach is armed and assuming a valid ILS signal is received the aircraft always assumes it will be an autoland. When selecting APP, with an autopilot engaged, the other two autopilots are automatically armed. Once below 1500' AAL LAND3 is annunciated on the ASA and the other 2 autopilots are engaged for the multiple autopilot approach.For the autothrottle question - on the real aircraft there are two autothrottle disconnect switches either side of the thrust levers that will, obviously, disconnect the autothrottle and the corresponding FMA will disappear. However, the autothrottle arm switch remains in the ARM position to be available in the event of a go-around or re-selecting any speed related autopilot mode eg. FL CHG. I haven't been able to find a way to disengage the autothrottle without disarming it on the PSS model - if anyone has please let me know! :-)The normal procedure for a manual landing is to disconnect the autopilot and autothrottle with the switches on the control column and thrust lever respectively. This would leave you with FD guidance for the ILS and manual control - with the AT still armed.Mike

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Hello Mike,Thanks for the detailed reply.Just a follow up on the AUTOLAND answer - so does the real world AC automatically switch to CMD mode on all three A/Ps? I guess thats whats throwing me off, as I thought all three would have to be manually selected. But, your answer makes sense.Quote:I haven't been able to find a way to disengage the autothrottle without disarming it on the PSS model - if anyone has please let me know! :-)The normal procedure for a manual landing is to disconnect the autopilot and autothrottle with the switches on the control column and thrust lever respectively. This would leave you with FD guidance for the ILS and manual control - with the AT still armed.Thats what I was expecting should happen too. Again - thanks.Joe Lorenc

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Pretty much yes! As soon as you press APP with an autopilot engaged the other 2 autopilots are armed, which is when the lights in the CMD buttons come on. However the other 2 autopilots are not actually engaged until LAND3 or LAND2 are shown in the ASA.This is one of the gotcha's for a single-engine approach. It's down to the pilot to control of the rudder until LAND3/2 is shown then the autopilot takes over the rudder as well as the rest. The autopilot keeps control of the rudder even in the event of a go-around. However as soon as any other autopilot mode is selected, it's back to one autopilot and pilots control of the rudder - if you're not ready it could come as a nasty shock with high power selected on the good engine and the rudder trimmed for approach power!Mike

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I haven't been able to find a way to disengage the autothrottle without disarming it on the PSS model - if anyone has please let me know!I believe I may have found out how to do this - in the KEYBOARD COMMANDS there is a option called Thrust lever AT disconnect switch push. I assigned it a key and am trying now. Withouy your description of the RW set up I never would have guessed it. EDIT - just to add - the switch is on the thrust levers in the VC also - no documentation that it is there (that I find), but none-the-less there it is.Joe Lorenc

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