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VNav Descent Profile - End of descent position?

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Flying some very basic routes into EGLL, when I insert the runway into the CDU it produces the expected "CF" point at about a reasonable glidepath intersection point. The programmed VNav descent then accurately brings me to this point at the end of descent ie with very little [zero] time for slowing down and dirtying up the aircraft. We then end up in a great rush to get things done. I have tried using the Des Now command on the VNav page - this starts the descent immediatly but programmes the descent to achieve the same result - end of descent just about coincides with the "CF" point.I know that I can revert to "manual" autopilot control of the descent; however, very grateful if anyone can show me how [if] the VNAv end of descent point can be changed to allow the aircraft to level off at say 10 nm before the glidepath intersection.By the way - for PSS - looking at some of the more recent problems highlighted on this forum, the only one I see is that the green external power "on" lights do not illuminate in VC [they are ok in 2d panel and the avail light and switch action works in VC] otherwise A/T, A/P and autobrake all ok with my installation.Mant thanks for any help with the CDU descent.John Rooum

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Hello John,You have three options.1) Change the distance where the CF is drawn (ie by default its 12 miles so set it to 15 which will give you the space to slow down).2) Create a point x DME before the CF in the CDU.3) Set a speed constraint for the CF as well as an altitude.Unfort I am at work at the moment so don't want to give you the steps by steps just in case I get it wrong and cause more confusion!All three steps should be in the manual, but if your still struggling just post and Ill look into it when I get home :)http://i31.photobucket.com/albums/c390/BTr.../phxbanner2.jpg

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Michael,Many thanks. For your info, my CF distance is invariably set at 8 nm - a bit tight for a Dash 8 let alone a loaded 777!However, I did not realise that I could set altitude constraints for way points that I produced [i had rtfm - several times - but missed it] and that of course solved the problem.All well on that front - now I am trying to find out why my reverse thrust selection no longer works unless I manually disconnect auto throttle once on the ground. I know that this is a known problem but oddly enough for my first dozen or so flights I had no problems and even now it works perfectly in the rejected TO case.

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Hi Michael,Just tried:1. Rebuild FS9.cfg2. Re-install joystick3. Remove 777 and re-install.Nothing effective. I have just flown 8 ILS at 2 different airfields with a VRef of 162 kts. In every case, I pressed and held F2 at touchdown [as the autobrake came on]. The best I got was A/T disengaging and Rev engaging at 120 kts; on most it was about 90 - 70 kts when Rev engaged.The only option left would be a re-install of FS9 [Not yet please - I did it a week before I got the 777 and it took a couple of days!]I know PSS are looking at this but one question - do you know what is the programme control for A/T disengage: weight on the wheels, a certain rpm, or a certain speed or something else???RegardsJohn Rooum

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John,Just confirm a VRef of 162 kts?? That corresponds to a weight of about 590ooolbs, waaaay above Max. Landing Weight, regardsless of which variant you use.

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Indeed it was - I first came up with this Rev Thrust problem when I flew acouple of very light positioning sorties [no pax, no cargo, 15%-20% fuel]. So I tried the other extreme to see if weight on the wheels had any affect - it didn't but the sim landed very smoothly even at that weight!

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Hello John,Still at work lol but just thought of something for you to try.Let the A/P and A/T work down to DH then disengage A/P and A/T (Note the A/T switch to the bottom right of the FD switch NOT the A/T ARM switches above CLB CON).Get to 50ft, hit F1, touchdown and hit F2 and let me know how that goes.Thinking (god it hurts!) I have had REV when flying manually, however haven't when doing autolands to test other peoples problems. Worth a try anyway!http://i31.photobucket.com/albums/c390/BTr.../phxbanner2.jpg

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MichaelJust run that option - no problems, Rev engaged as soon as I selected F2. In fact that is what I have seen all along if I manually disengage A/T. The problem seems to be that whatever is to command the A/T disengage at touchdown is not very well defined.In fact I have noticed a couple of oddies like this - for example, the conditioning summary that should appear at the bottom of the right hand EICAS in normal mode appears on some systems and not on others [i had it, then lost it?] I have a second system with just a basic FS9 and the 777 [very low performace AMD XP2000] and this shows the conitioning summary correctly??

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Hiya Mate,>Just run that option - no problems, Rev engaged as soon as I>selected F2. In fact that is what I have seen all along if I>manually disengage A/T. The problem seems to be that whatever>is to command the A/T disengage at touchdown is not very well>defined.Good good (if thats the right terms to use lol!). Like you say it seems that it enters the rollout mode but doesn't disengage the A/T. Will get it looked into :)>In fact I have noticed a couple of oddies like this - for>example, the conditioning summary that should appear at the>bottom of the right hand EICAS in normal mode appears on some>systems and not on others [i had it, then lost it?] I have a>second system with just a basic FS9 and the 777 [very low>performace AMD XP2000] and this shows the conitioning summary>correctly??I know there is a problem for some people in that the pressurisation is showing in the 'mini' view and not the zoomed view. Could that be the difference between the two tests?http://i31.photobucket.com/albums/c390/BTr.../phxbanner2.jpg

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MichaelThe plot thickens. I thought my problem with the air con summary was due to a change I had made to the panel.cfg [pushback gauge] - no way. I have found that when I first load the 777, the air con summary is shown. However, when I load a flight plan into the CDU as I press "exe" the air con summary disappears. Crazy!I have tried it with a flight plan input manually leg by leg, with an imported FS flight plan and finally with the tutorial flight plan. I had saved that when I first flew the tutorial so I imported it, selected activate [ok] then pressed "exe" and the air con summary immediatly disappeared.I know this was mentioned in earlier threads and I was under the impression that PSS said it worked ok at their end. Could you try; check whether it is my system or a genuine bug.Many thanksJohn

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