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Guest Dashik1

757 CAT3 Autoland Problem.

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Hi Now I might not be the sharpest pilot out there but you can call me amazed when 50' from touchdown at EGLL form LFPG on RWY 27R the aircraft did a sudden violent roll to the right! I only just managed to recover and land but had to call the Vatsim Emergency Vehicles out as I came to a stop to the right of the runway and stuck in the MUD!Surely in good weather (AS6) this aircraft should be capable of a full CAT3 Autoland online with Vatsim? Or did I screw up?

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>Hi Now I might not be the sharpest pilot out there but you>can call me amazed when 50' from touchdown at EGLL form LFPG>on RWY 27R the aircraft did a sudden violent roll to the>right! >>I only just managed to recover and land but had to call the>Vatsim Emergency Vehicles out as I came to a stop to the right>of the runway and stuck in the MUD!>>Surely in good weather (AS6) this aircraft should be capable>of a full CAT3 Autoland online with Vatsim? Or did I screw>up?Make sure you sign your posts! (Norm will get ya if you don't ;-)) I've attempted a CATIII myself and I was in 19kt crosswind gusts. No problems. Hopefully someone else can give you some better help, but that was my experience.

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>>Surely in good weather (AS6) this aircraft should be capable>of a full CAT3 Autoland online with Vatsim? Or did I screw>up?Without experiencing this myself, or other reports of this issue, it may have been ASv6 throwing in a thermal, or if you where behind other traffic on approach it may have been wake turbulance.I will try some catIII landings today and see if I can reproduce.

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Thanks for the reply, Its not a moan lol just an observation I'll try it again later.To be fair the Vatsim ATC controller did kick a guy for sitting on the runway doing nothing and being unresponsive as I was on short finals so yes, its possibly a glitch from that.In anycase i'm sure its just a minor prob. I'm VERY happy with the aircraft and think its well worth the

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I had exactly the same issue!!I did set the decision height for 200ft - thought this could have beenn the problem - did you set decision height?It caught me out as well - I killed all onboard and got offline ASAP due to being very red faced!!!

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Well the PSS 777 just did the same thing! I flew the same route and came in for a Cat3 Autoland on 27R at EGLL. The whole approach smooth as you like then the callouts start 50,40,30 etc and at the same time the aircraft rolls to the right and the wing strikes the ground and BOOM!I have the V2 patch installed and was flying online (vatsim) with AS6 with the latest update etc.Land 3 was displayed in the EFIS along with Rollout and Flare!Bit peeved TBH! I'll try turning off wake Turbulance in AS6 but there was no other aircraft at or near RWY 27R for about 20 mins before me at 1:10 am monday morning! So surely the turbulance should not affect it?Anyway I'll try it tommorrow night and if it works ok I'll post here!

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Try at other airports. It looks like this may be an AFCAD issue with that runway . . . I have had this happen before as well and it always turned out to be AFCAD or scenery related.I'll fly into EGLL on a CAT III first thing when i get off work (8 hours from now). I have ASv6 as well. can you paste here what the conditions were at the time so i can do a precise try at your conditions? The only difference is i will not be on AVSIM as I do all my flying offline with 100% AI and Ultimate traffic installed.I did do successful CAT III's into KDEN with no issues, and amazingly i did a CAT III into KPUB -- gotta love FS -- KPUB isn't even CAT III Capable LOL. in FS, though, an ILS is an ILS :-P

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I'll try at SFO here in a sec also.I've never had the problem again after turning off wake t....other then that I don't what to tell you all.

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Just tried it again and no problems.The only problems I ahve are with the Navdata not getting updated correctly in the FMC. The FMC says it has the correct dates but the procedures and data are outdated. Very weird.

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Jeff,The navadata is the latest airac - ie airways and waypoints. SID & STARs however may be behind but thats down to a lack of updates available.

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Hey Norm,I tried it both ways from the Navdata site with the current cycle which it says is avail for PSS add ons. I first tried just the AIRAC then I tried the AIRAC with a SID/STAR all in one file.In both cases the FMC recognized the correct data set but the actual data seems to be not taking (i.e it still says ROCKI3 instead of ROCKI4 for KDEN). Very weird, I've never seen that before.There's quite a bit of other strange happenings also, but I suspect it's due to the data itself.One of these days, I'll get around to buying and trying out the '57. I've just got around to the T7 now...ROFL. I'm way behind these days, but you know why. :-)

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It was a lateral-directional departure from controlled flight, (first stage of a stall or spin). If your airspeed was correctly selected and maintained, one possible contributor might have been a low frame rate, disabling effective aircraft control of the autoflight system, during very short term deviation form desired parameters.I have seen this in the following PSS aircraft, even at VREF + 10 with calm air:a. AB pro (319, 320, 321)b. AB 330c. FS 2004 B777I'd guess they all might be using similar equations of motion/ stall algorithms.

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Right, Off to try again, I did a quick experiment earlier with, as was suggested earlier in the thread, the AS6 Wake Turbulence switched OFF. 757 approach to rwy06 Edinburgh EGPH. This appeared to sort the problem so I will try again with the 777 and if I get time I will also use the 757.Jsut so you know I am otherwise Very happy with the PSS aircraft and consider them good value for money.The landing problem is the only problem I've had.

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I have suffered this exact same problem on the 777 with Patch 2 installed - at the end of a KSEA-EGLL sector, carrying out a CatIII Autoland on 09L @ LHR in calm winds, CAVOK. Flaps were set at 25, and I had VRef+5 dialled into the MCP (about 170kts) if memory serves. I had the DH set to 200ft Radio, and the approach was proceding normally (LAND3 was on the PFD). Somewhere between 50 and 30ft, the aircraft rolled sharly left / nose down and struck the ground. I suppose it could be something in the code for both autopilots relating to the AP transition to FLARE (is there some common code between the 757 and 777 in this area).I don't have any other add-ons installed, just a clean copy of FS9 and the PSS 777.Could Norman and the guys at PSS look into this??Daniel Percy

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Just out of curiousity do these approaches that you are having issues with, do they have a missed approach component? After the threshold does the route end, or does it show a missed approach escape route, that maybe incorporates a steep climb/turn. If it does try removing the missed app part and see if the issue still arises.

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Steven,Look up in the thread for my input on why it happens. I had experienced it numerous times on the mentioned aircraft without ActiveSky, or any weather at all.LHR has no missed approaches programmed AFAIK. Even if it had, the first portion is always a climb on runway heading.>Just out of curiousity do these approaches that you are>having issues with, do they have a missed approach component? >After the threshold does the route end, or does it show a>missed approach escape route, that maybe incorporates a steep>climb/turn. If it does try removing the missed app part and>see if the issue still arises.

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I do notice that the autoland puts the bird down excruatingly hard. My last autoland attempt in the 757-200 was -370ft/min which I feel is a bit excessive. Easily fixable.

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Tried a CAT3 landing agion this morning and it rolled right and I only just cayght it! I'm going to uninstall/reinstall then start paying more attention to whats happening when I land.that way I might be able to provide some more accurate info.The problem only occurs when its at the 50,40,30 callouts if you know what I mean, right about where I would expect the flair.

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OK just to update this.Its all sorted. It turns out a previous poster was right. turning off the wake turbulence in AS6 sorts the problem and CAT3 Autoland's are no porblem now when there set up properly and I get the glideslope from underneath.Thanks for the replys guys.James

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>OK just to update this.>>Its all sorted. It turns out a previous poster was right. >turning off the wake turbulence in AS6 sorts the problem and>CAT3 Autoland's are no porblem now when there set up properly>and I get the glideslope from underneath.>>Thanks for the replys guys.>>JamesExcellent. Glad you found the issue :-)

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I had posted 2 photos of an aircraft flaring in LFPG autoland, rolled 25 degrees or so to the left 30 feet above the TDZ.It was not due to external disturbance, and the photos posted showed the aircraft controls had commanded the roll. AS6 wake turbulence was off. Believe good news after verifying it.>>OK just to update this.>>>>Its all sorted. It turns out a previous poster was right. >>turning off the wake turbulence in AS6 sorts the problem and>>CAT3 Autoland's are no porblem now when there set up>properly>>and I get the glideslope from underneath.>>>>Thanks for the replys guys.>>>>James>>Excellent. Glad you found the issue :-)

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>It was not due to external disturbance, and the photos posted>showed the aircraft controls had commanded the roll. AS6 wake>turbulence was off. Believe good news after verifying it.It is verified on some systems. This issue seems to be system related -- otherwise why would only some folks be encountering it and others not. So for some of us it is good news, and believed.Try playing with some settings. You'd be surprised what you might find.maybe i should be more specific and merely reply "Glad you found the issue on your end" . . . Different systems -- different strokes. And mine is a low end system.

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Chris,I previously wrote that I had encountered this behavior on FS2000/2002 Pro with PSS A319/320/321 Pro, AB330, and on FS9/9.1 with PSS AB330, B773ER and B752RR, and those only. No AS was used then on the former FS's, and FSUIPC of various versions only on FS9 if I recall correctly.If it were AS, it should look like an outside disturbance, but the last case I reported is documented well enough to suggest that it is the result of aircraft control input during autoland flare.Regarding the suggestion that it is system related, that could well be, such as an interaction of the above PSS aircraft with the above FS variants. In my words, the PSS control logic used. The older B744 and B777 never did that, which might lead somewhere. Also, I own and fly every conceiveable modern quality FS9 add-on aircraft, but have not seen it there.

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