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johnk51

End of Route

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There are times with the T7 and 757 that when doing an autoland at about 50 over the threshold you get the fmc message end of route. At that time the plane starts a hard left bank. It doesn't happen at all airports. I know KDEN 16R, EGLL 9L this does happen. But other airports like KLAX, KSFO it does. These examples are all addon airports. Maybe at the end of route the plane doesn't know where to go. And again this is doing an autoland.

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John,I have seen reports of this issue, and to date have been unable to resolve it. For me it only happens at one airport I use with add-on scenery.What I have isolated as a major possibility is the FS default GPS reading for the airport. I.E. each airport file has a value designed to allow the nav programs to "know" when they have reached the airport. I am believing that with some scenery packages they relocate the runways so that this "spot" or value is not aligned correctly and as such the fmc reads this value, and closes of the route.I hope this makes sense... it does in my mind...

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I've not got a problem with the FMC clearing the route over the numbers, but the problem is it also clears the ILS frequency as well, which is what causes the aircraft to bank before touchdown.I've seen it quite a few times when manually landing - you get to about 100 feet, you get an FMC end of route message and the flight director yanks off to the left, making autolands rather hazardous.Could there be some way of delaying the FMC end of route until you get below a certain speed for example, or if thats not possible, not clearing the ILS freq when the rest of the route is deleted?

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Its not an addon scenery issue, as the "End of route" problems happens to me at all airports.I Have London Gatwick and Heathrow sceneries from UK2000, I get "END OF ROUTE" before touchdown on all runways, yet with PMDG/LDS aircraft the FMC's act correctly. This problem must be within the gauge file.Cheers

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Just curious,Are you all entering the full approach from a chart, or relying on the PSS default CFXX fix and runway ?I have long since parked both PSS Boeings for a plethora of other reasons, but can honestly say I never had this particular issue when manually entering a full approach procedure, with missed approach, etc.Why doesn't the PSS FMS support approach procedures, anyway ?

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Good point Brian. It's sometimes a bit limiting with regard to the STAR data avaliable as to whether there is a missed approach procedure or not. I suppose to could enter a fix after the runway manually to extend the route past the landing runway. I can't remember ever seeing missed approacg procedures when using the 777.I guess as soon as you reach CFXX, which will be the last point on the plan, the FMC will have no more route to follow, so clears the FMC.

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Surely you should only get an END OF ROUTE alert if LNAV is still active. On final approach you will normally not be in LNAV, so this FMC alert message should be inhibited.Kevin

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Most popular commercial add-ons have this message appear.

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Not 100% sure, but, even if not in LNAV, the FMS will still sequence the approach waypoints as you fly the approach, regardless of whatever other mode you choose to fly the approach under.If the runway is the last point in the route, the scratchpad message does make sense. I also seem to remember that LNAV and disco messages are not inhibited as are VNAV messages, but I'd have to dig for more details. I really think the bigger issue here is not having any sort of missed approach segment(s) after the runway.The other issues mentioned certainly are a problem...even with an end of route, and flying the approach in LNAV, the AFDS should only degrade to HDG HLD.If flying in APP mode, what are the NAV radios doing before this happens ? What mode is the ND set to ? Maybe as a temp solution, be sure NAV radios are in MAN mode regardless of any other settings and tune manually ?

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The ILS has to be tuned through the FMC - you can't do it any other way, and the problem is it gets deleted just before touchdown.As Brian states, why the FD yanks off to the left is anyones guess.This is a major issue PSS - at the moment I cannot trust either the 777 or the 757 (which is in the hangar again awaiting the VNAV fix...) with making an autoland.Regarding Stevens post, most popular commercial addons alos have the End Of Route message inhibited until the ground speed is below a certain limit to ensure that these sorts of problems don't occur.

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I tested the 753 into KPDX just now. I was going 10L 111.30. I was in 2d with the fmc window open to the nav radio page. As soon as I got end of route both radios changed freq and this time the plane did a hard bank to the right. Vor L went to 111.8 and vor R went to 109.2. I don't know what freq is 109.2. 111.8 is the pdx vor. So I think that you need to put the radios on manual park both radios for this not to happen. I'll try that sometime this weekend unless some one else gives it a try.

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Just a quick question...if you put the ND in ILS mode, do the radios go into manual mode ? This shouldn't happen anyway, but I'm curious....

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Just did a flight in the T7 from KBOS to KDEN. Landing 26 and manually parked the ils in the radios. When end of route message appeared the radios stayed on the ils freq. So it looks like you need to manually park the ils. Haven't tried it on the 757 and there, there's the button for auto and manual on the main 2d panel. I'm guessing you have to click on manual then park the ils in the fmc.

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That's interesting, at least now we're getting somewhere...For the 757, putting the EHSI in ILS mode should switch the radios over to MAN, again maybe as a temp workaround....

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>Not 100% sure, but, even if not in LNAV, the FMS will still>sequence the approach waypoints as you fly the approach,>regardless of whatever other mode you choose to fly the>approach under.>>If the runway is the last point in the route, the scratchpad>message does make sense. I also seem to remember that LNAV and>disco messages are not inhibited as are VNAV messages, but I'd>have to dig for more details. >>The point is that END OF ROUTE is a warning that you have passed the last waypoint and the AFCS has consequently switched from LNAV to HDG mode. If LNAV is not active this won't happen, hence no need for a message.On the turn to the left issue, maybe the AFCS is going to HDG SEL mode instead of HDG HOLD? The heading bug should always be kept aligned manually anyway, but if you forget, the sim would follow whatever heading you last had selected.Kevin

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>Most popular commercial add-ons have this message appear.That doesn't necessarily make it right.In the PMDG 744 I believe END OF ROUTE comes up as a status message in white on the FMC but with no EICAS message. I'm not sure this is right either but at least it's not distracting. I'm only going by what I have read in the FCOM, but I concede there may be customer options which affect the logic too.Kevin

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>>Most popular commercial add-ons have this message appear.>>That doesn't necessarily make it right.Kevin,I realise this, I was just making the comment that it is not a "issue" isolated to the PSS aircraft.

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"The point is that END OF ROUTE is a warning that you have passed the last waypoint and the AFCS has consequently switched from LNAV to HDG mode."As I understand it, END OF ROUTE is just a notification that you've reached the end of the active route, no more, no less. If in LNAV, the autopilot reverts to HDG HLD because there is no active leg to fly, same as with any discontinuity. I'm also kinda confused by this statement:"If LNAV is not active this won't happen, hence no need for a message."The FMS will indeed still sequence waypoints even if not under LNAV guidance, so I'm not sure what exactly you're saying here. I'm also pretty sure that the message is only inhibited on the ground. With all of this, I'm happy to be proven wrong, though. :)"On the turn to the left issue, maybe the AFCS is going to HDG SEL mode instead of HDG HOLD? The heading bug should always be kept aligned manually anyway, but if you forget, the sim would follow whatever heading you last had selected."Could be, I dunno, but if the AFDS is coming out of APP into HDG SEL OR HDG HLD because of an END OF ROUTE scratchpad...well...that's just not right, as I'm sure you already are well aware :-lol

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Hi All,I have been watching this thread over the last few days; and as I have just flown some 15 auto-ILS to autoland in the 777 {looking at a separate problem on STAR tracking}, you may be interested in how the 777 reacts on my installation:1. At around the 100 ft call, the CDU shows the end-or-route message. I see no change on the Nav radios and the AP appears to remain in APP mode tracking LOC and GP.2. At around 80 ft, the FMC enters the landing phase. The glidepath is disconnected but the AP remains tracking the LOC as the aircraft starts the landing.{APP off, LOC on}3 At around 30 ft, throttles retard to idle and the flare starts.4.At touchdown, LOC is disconnected {light out}, the AP light remains illuminated, but with no mode lights, and yaw control is disconnected from the AP to allow rudder control for the manual roll-out. {Auto-rollout is not modelled} Manual Aileron and elevator control is inhibited until the AP is manually disconnected.I emphasise that this in on my systems. With the original 777 release, I occasionally saw the turn problems just before touchdown but I have never been able to reproduce them since the first update.I'll try a few sorties in the 757 next although, again, I have never had this problem with that aircraft.John Rooum

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>"The point is that END OF ROUTE is a warning that you have>passed the last waypoint and the AFCS has consequently>switched from LNAV to HDG mode.">>As I understand it, END OF ROUTE is just a notification that>you've reached the end of the active route, no more, no less.>If in LNAV, the autopilot reverts to HDG HLD because there is>no active leg to fly, same as with any discontinuity. >>I'm also kinda confused by this statement:>>"If LNAV is not active this won't happen, hence no need for>a message.">>The FMS will indeed still sequence waypoints even if not under>LNAV guidance, so I'm not sure what exactly you're saying>here. I'm also pretty sure that the message is only inhibited>on the ground. With all of this, I'm happy to be proven wrong,>though. :)>>"On the turn to the left issue, maybe the AFCS is going to>HDG SEL mode instead of HDG HOLD? The heading bug should>always be kept aligned manually anyway, but if you forget, the>sim would follow whatever heading you last had selected.">>Could be, I dunno, but if the AFDS is coming out of APP into>HDG SEL OR HDG HLD because of an END OF ROUTE>scratchpad...well...that's just not right, as I'm sure you>already are well aware :-lol I'm only repeating what it says in the aircraft manual, that LNAV must be active for the alert to be given. OK it's for a 747-400 (I don't have access to a 757 one at present), but the logic won't be much different for the 777, and likely very similar for the 757 too.Even though the FMC is always sequencing waypoints, if LNAV is not active it is not in control. The alert is there to warn that LNAV has been disengaged because the last waypoint has been passed. If LNAV has already been disengaged by selecting HDG or engaging LOC then an alert is superfluous.As to your last comment, absolutely agree of course.Kevin

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Well, I guess we'll leave it at that then.I do find it curious that a standard disco will generate a message, but that an end of route shouldn't, though I have nothing concrete to back that up with.At any rate, this is really tangential to the more serious problem with the AFDS dropping out of APP mode. More accurately, what seems to be happening s the FMS is autotuning the closest VOR(s) at end of route. Since this a/c incorrectly uses NAV1 for ILS purposes...well, you get the picture.

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