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Guest pedroz

Waypoint overshooting issue

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Guest pedroz

Hello PSSThis time I would like to hear from you as this is a clear issue which deserves the right answer or either to at least consider it for the future patch;I said in another thread:When angle to next waypopint is superior or equal to 90

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Same here! Unable to fly the ARC, because this plane will notaim for the first waypoint on the ARC....it will keep on going straight and keeps on going.... :(This bird will sit in my hanger till major repair are accomplished.Bill ReynoldsCaptain, Japan Jet NetworkSupervisor, VATSIMRL AMT B777/B767/B757/B747/B747-400/B737[/img]http://online.vatsimindicators.net/810046/2540.png[/img]

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Guest aarskringspier

>can you provide more details on which STAR you see this with,>thanks>>>John>PSS SUPPORT>support@phoenix-simulation.co.uk>>http://www.avsim.com/pss/phoenix.jpgIts not really a STAR; its with any severe angle on a turn. When turning to intercept a way point on say a 90 degree angle from your current track the plane will over shoot your route by a wide margin and then take a long time to track back unless you use the direct to function on the FMC.

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I came out of EGKK on 08R and used the SAM2P departure last night.AP on, AT on, LNAV on, VNAV on, initial climb to 3,000 feet as expectedPLane failed to make the first turn, ignored the first waypoint and had to be manually flown to reintercept.Having failed to find the first waypoint it showed up DET36 as the target, but would not intercept the route until DET36 was replaced by moving DET44 up on the FMC so that it replaced DET36.After that all OK. It seems that very tight turns are the problem as having missed the first waypoint, the aircraft headed off in the general direction of Europe instead of the US.I tried an approach into Innsbruck (LOWI) abd found that the plane missed two waypoints and took a shortcut such that it missed the correct approach path and failed to intercept the ILS.Same thing happened at EGKK landing on 26L. The approach should go via Mayfield (MAY) VOR but it cut back inside the line and ended up at 3 miles from the touchdown point at 3,000 feet, not where it should have been.It seems to me that the FMC is too happy to cut out waypoints if it thinks there's a shorter route.Hope this helps.Richard

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Hello Randy,Sorry to say this, but you are wrong. There are 2 maths formulas to correct this, that every pilot use everyday they fly not to overshoot ILS when flying manual. It is called turn anticipation.One of the first is the turn anticipation to enter an arc DME.1/3Tasdivided by D where D is the distance (example 20 if the arc is at 20DME from the VOR). This will give you the distance from that VOR to start your turn to remain +or-0.5 dme from the given published distance.The other one is the turn anticipation to get out of the arc to intercept an ILS for example or a given course. The formula is the following for a 90

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Guest sb55mv

Hello Cyrille,I think that the main issue has somehow been clouded by the actual explanation of the internal workings of the CDU/FMC.and, it does not really help nor solve the problems that I,and the other pilots are having.for example, I do not recall reading anything in any way pertinent to this issue in any of the manuals.whilst not wishing to compare this fine product to any other makes, such as the usual ones, they do not give us this problem. they do in fact, follow the plan we have in the SID/STAR section,if what you are saying is the real world and factual way things are done. then this is all well and good, but, I think the point we are trying to make is why does the PSS one differ so much. what then is the point of having a SID/STAR in any of our plans if the B777 decides that it just does not want to track them. I too have missed many ILS interceptions because the CDU/FMC decided that it could do better than the actual track I had inserted. and, we are constantly monitored by the VATSIM Controllers who,in airports such as EGLL where EGSS,EGKK,EGLC are in close proximity, will ask us straight away why we are deviating from our plan.that is what we are trying to find out.many thanks,

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Guest aarskringspier

>Hello Randy,>>Sorry to say this, but you are wrong. There are 2 maths>formulas to correct this, that every pilot use everyday they>fly not to overshoot ILS when flying manual. It is called turn>anticipation.>>One of the first is the turn anticipation to enter an arc>DME.>1/3Tasdivided by D where D is the distance (example 20 if the>arc is at 20DME from the VOR). This will give you the>distance from that VOR to start your turn to remain +or-0.5>dme from the given published distance.>>The other one is the turn anticipation to get out of the arc>to intercept an ILS for example or a given course. The formula>is the following for a 90

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Guest Phoenix_7

I just tried a 180 deg turn using both the LVLD767 and PSS777, the 767 took 6.6nm to complete the turn, the 777 took 7.2nm, this was using HDG SELPerhaps the turn radius you are trying to complete is not achievableJohnPSS SUPPORTsupport@phoenix-simulation.co.ukhttp://www.avsim.com/pss/phoenix.jpg

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Guest sb55mv

Hi John,we are talking about Way Points here, try it with a flight plan using a SID and STAR. and make sure it's a challenging SID as well, not one in a straight line.I will try and attach one for you.it's an FS Nav Plan, just import in into the T7

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Guest pedroz

Hello John:I have a STAR for Mexico city airport SLM1 which is:....PCA STAR initiation: SLM, Radial 255

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Hello,I wrote this up soon after the B777 launch, but have not seen a reply. I mentioned that the aircraft normally maintained up to 18 degrees of bank with the bank limiter set at AUTO. This bank limit is too low, as evident by a 25 degree selector position. Referring to PSS replies to this topic, the aircraft I believe is designed to follow published terminal procedures for major airports, and perform at least a rate 1 turn at or below 250KIAS.The problem is evident in my cockpit in various common navigation situations, as the original writer explained.>Hello PSS>>This time I would like to hear from you as this is a clear>issue which deserves the right answer or either to at least>consider it for the future patch;>>I said in another thread:>>When angle to next waypopint is superior or equal to 90

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