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guy

777-300Er unstable on autoland

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On autoland the 777-300 balances from left to right.With no wind it is a light ,almost imperceptible movement , but with wind(even light) it is relatively pronounced.I have not seen this on the 777-200.Guy

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I use the Justflight CD version with patch.The date of PSSB773ER-GE.air is 8/04/2006 21:59.Guy

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Only JustFlight can tell you if the file date is correct. It sounds around the right date though.

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I asked the question on the justflight forum.Didn't get any answer.As I applied their patch I suppose I have the right airfile.The 777-300 has also a tendency to turn into the wind on rollout!Guy

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Not always the case, and its why I asked for the date. If you have not done so, I would redownload their patch since there was an issue with the 300 air file patch although this was replaced quite quickly.

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Downloaded it on the 15th of May.So it must be the good one.Guy

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have made some research on the Justflight forum.Found a thread "patch 1.1 NOT UPDATING THE b777-300 AIR FILE ".In that thread yourself intervene and say that you sent a new airfile, that was the 9th of april!Guy

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>In that thread yourself intervene and say that you sent a new>airfile, that was the 9th of april!That may be so, but what JF did after that I don't know. I do however have no doubt they rolled it out.You will need to ask over at their forum since they are the folks who sold you the product. Thanks,

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Martin from the Just-flight forum has answered: I have the right 777-300 airfile, the same he has.He asked also if I load first the default-aircraft, which I always do.To be sure I nevertheless reinstalled the aircraft and the patch.But the problem is still there, there are even 2 problems:1) when auto-landing with sidewind(8 or 16kts) the 777-300 has bank-oscillations which increase when I approach the runway.2) on autoland after touchdown (still with sidewind) that is during autoroll, the 777-300 and also the 777-200 turn or slide to the side the wind is coming from. It is difficult to stay on the runway in those conditions. I have made some research on this forum and seen that this has also been signaled (after the patch) by others (see for exemple the thread:"Aircraft still unsteady when landing").Fortunately handflying the approach and landing is easy.Guy

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I did not have the time to check the manual, but isn't autoland limited to a 10Kt crosswind component?

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Guy,1. The PSS 777 does not have auto roll out so you need to disconnect the AP on touchdown in order to control the xwind.2. I believe that there is a rw xwind limit for auto-land - I know you can get "30 kt fog" but normally I am sure this sytem is only used with very little wind. As far as the PSS 777 is concerned, I have the patched LR and this will auto land with a 16 kt xwind component - it tracks the LOC very smoothly to touchdown but you have to be quick in disconnecting the Ap and gaining manual control of rudders and aileron.How is your LR with a 16 kt xwind?John R

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The side-wind limit for the 777 must be something like 20kts, I think. But the oscillation problem on the -300 exists already with 8 kts .My 777-200LR also turns into the wind (8 kts sidewind) on autoroll.The pss 777 does nor have autoroll? But it is indicated on the PFD!Or is not functionning ?Perhaps Norman say something about this.I got also another interesting message from Martin on the justflight forum:"As promised I did test the ER with an autoland and I can confirm that I am experiencing the same issue.On approach with a 12 kts crosswind the ER was unstable at 3.5 miles out rocking noticeably on approach. It's almost as if the aircraft is experiencing a much stronger crosswind than it actually is.As for the rollout I found it necessary to disconnect the AP sooner than normal to prevent running off the runway."Happy (auto)landings to all.Guy

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Did some research on crosswind limitation.Found this interesting article by a real 777 pilot on the site "Flying safely on the 777 "(http://www.geocities.com/khlim777_my/asFAQ29.htm#whyd):"There are 4 crosswind landing techniques on a Boeing 777, namely, 1. Side slipping (zero crab)2. Crabbing - for slippery runway3. De-crabbing - removal of crab during the flare4. Combination of crab and sideslip.In order to use any of such techniques, there are crosswind guidelines. For instance, when applying the crabbing method, the limitations vary according to the existing runway conditions: If it were dry - 45 knots; wet - 40 knots; standing water or slush - 20 knots; snow, not melting - 35 knots and ice, not melting - 17 knots.If the pilot decides to use the side slip technique, (zero crab) the crosswind guideline is restricted to 40 knots. When executing the side slip, over controlling the roll must be avoided because any excessive bank could cause the engine or outboard wing flap to contact the runway.When applying the de-crab technique, the touchdown is made with cross control with both the gears touching down simultaneously. The upwind aileron is used to keep the wings level.On a slippery runway, when using the crab technique, the crab angle must be maintained until touchdown. In this way, the pilot workload is reduced when proper rudder and upwind aileron is maintained.Some pilots prefer to use a combination of the crab and side slip technique. As upwind gears touch down, a slight increase in downwind rudder is applied to straighten the nose. Simultaneously, the aileron is applied to maintain the wings to keep them level.Phew!! A pilot needs to work quite hard if the wind approaches the limit! The difference between a Boeing 777 and a light plane like a Cessna 182 or Piper is the strength of the crosswind. I believe the airplane manual for the light airplanes would recommend the appropriate techniques."On another site of the Chicago O'Hare airport they say that crosswind limitaion for all heavies is 20 kts.On the site "Landing/Autopilot Question for the Heavy Drivers" (http://glocktalk.com/sitemap/topic/210409-1.html) they say : "The headwind/tailwind/crosswind limits required to autoland vary by aircraft but generally 25-30 kt HW/XW limits and 10 kt tailwind limits are pretty normal for heavy metal jets. In lower viz Cat 2/3 approaches, a 10 kt crosswind generally applies"Guy

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Norman,Does the 777 have autoroll, yes or no?Guy

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GuyJust watch your ILS indications on touchdown. Just before td APP goes out and LOC illuminates, then at td, LOC goes out. The ap is still engaged but there is no mode light on.John R

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John,I have seen that now: the Loc light goes effectively out after touchdown, as you said. So probably you are right, the automatic rollout is not functionning at all.That would also explain why the Pss guys have become silent on this.Guy

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>That would also explain why the Pss guys have become silent on>this.Guy,Silence means nothing. I notice the exact same thread over at JF's forum which Martin has just replied to.

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Norman,I still do not know your opinion about this rollout thing.Guy

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Guy,As a support forum, we support our customers. As we both know, your custom is actually with Just Flight since they are the guys who took your money.My personal opinion which you seek however I give freely. Autolands are not my thing. Despite being an Airbus guy I would much rather fly with hands on from 10k to the surface. For me, FS is all about the actual flight planning and the instrument work involved in flying a departure or an approach by hand.

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Norman,I am almost sure Pss got at least a part of my money for the 777.I am a long-time Pss customer since the Fs2000 days. Had the old 777/747 and still have and fly with pleasure the A320/A330/A340 and also the Concorde on FS2004.All great planes and the new 777 for Fs2004 is probably the best of them all.I like both handflying and automatic flying.And I suppose that Pss did all this programming not just for fun , but so that we can use it. For pure handflying I can use the default 777.I ask some questions about things I see and would be interested in an answer.With all respect, if you don't know the answer, couldn't you ask or transmit to someone else in the team ?Because, where can I ask them, if not here, on this forum?RegardsGuy

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GUY,If you got youre 777 from Just Flight ..Then you really should ask them in their own support form..And you saying the 777 goes out of controll when you have it in autoland? Is youre C/G (Center Of Gravity) Correct..Are you disconneceting the A/P when you touch down.?James

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JamesHave a look at the JF forum and you will see that he has two problems:1. AP oscillating when tracking the ILS LOC in the ER - more pronounced as xwind increases. This has been reported before with the ER - I have the LR and have never had a problem so I guess it must be something in the FDE as I assume that both share the same panel including AP?2. He assumed that the PSS 777 had auto rollout.The first problem might also be something to do with his kit - the only way that I could reproduce the AP problem in the LR was by reducing FPS to very low single figures.As to the second, all he needed was a one word answer - whether rollout was modelled or not. Unfortunately neither Just Flight nor PSS have been able to provide a definitive answer!John Rooum

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Hey John,i wasnt trying to be a smart*** i was just saying if he had tried any of the things. Like disconnect A/P on touchdown...And as far as JF. That is the reason i dont buy from second hand companys..If PSS makes the model and all that i will buy it from PSS..Not that i am saying anything is wrong with JF. And as far as me i dont have a problem and i only fly the 200lrJames

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JamesHey, I was not getting at you. Also I agree your point about buying from companies such as JF - although their support is now 100% better than it was a couple of years ago.My point was that, in these support forums, I think those such as Guy could at least expect to be given definitive answers on what is modelled and what is not. It saves an awful lot of hassle and wasted time.RegardsJohn

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