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Guest vcom

>John's info was that it couldnt be modelled in FS9.Why not? Sorry but this CAN BE MODELLED it is POSSIBLE.PMDG 747 do this and Level-D 767 do too.Ernest.

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Guest Phoenix5

Ernest,If you read the next sentence to the post you quote, Norman states that John was mistaken on this occasion.

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Guest skippy

>FWIW, the workaround I use is:>1) On short final, ensure NumLock is off.>2) Upon touchdown, tap the 5 key on the numpad to center the>control surfaces. The PSS 777 will now roll right down the>centerline with only minor rudder input to compensate for any>crosswind you may have.>>Hope that works for you until this issue is resolved.>>JeffHi Jeff,I've done some more "test flights" and come to the same conclusion as you.1st Flight. Manually locked all 3 NAV Radios to the ILS. When established on ILS disconected Joystick and put FCTL on the Left Inboard Display to watch what was happening with the control surfaces under A/P input. Also popped an extra view window open and view a/c head-on. At main gear touchdown the a/c was reasonably centred on the RWY. However, as soon as the nose wheel touched down (and apparently still under A/P control) the a/c immideiately started it's left turn off the RWY. I noticed on the FCTL display that the rudder was centred throughout but the alerions were indicating a "correction" to the left.2nd Flight. Did all of the above but at main gear touchdown I pressed 5 key and continued to press it throughout the rollout. Although the a/c still tried to veer to the left, repeatedly centering the controls with the 5 key kept it reasonably straight. Thrust reversers didn't engage until almost stopped.I've confirmed for myself what others have posted - that something is amiss with the A/P on touchdown and throughout the rollout. Hopefully it is or will be addressed by PSS. It's a great plane but clearly has some bugs that need to be ironed out. I'm sure they will be. Norman, will you take.up this issue in "The Sticky" post ?CheersChris.

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Guest FlyinJ

Nice testing there Chris. PSS should put you on the Beta Test list for the patch. :)Jeff

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Jarrod:That is NOT the way things work in the real world! You don't land on any side, you aim for the center line...crosswind, no wind, headwind, hail, act of god, deer on the runway, etc... center line.Second, you don't want a few degrees of bank in an aircraft with wing mounted engines because you then run the risk of using your GE-90s as sleds. Sometimes it can't be helped but trust me it is seldom on purpose. Third, you don't kick out once the wheels are down, you kick out just BEFORE the wheels are down. Otherwise you will eventually overstress the gear and find that you are taxiing to the gate on your belly.Fourth, I am having the same yaw problem too. Once I touch down with any amount of yaw I start sliding towards the opposite side from where the wind is blowing. This is made worse since I am trying to disconnect the autopilot, autobrake and autothrottles because they won't disconnect themselves as they are supposed to so I find myself fighting the T7 all the way down the runway, taking out runway lights and unsuspecting groundskeepers mowing the grass as I struggle by.Similarly I am also havin the autopilot issue. Bank oscillations all the way down the glideslope (not as severe now I turned down my realism setting (argh!!!)). Still once on the ground unless I disengage the AP I'm certain to start heading towards the grass with even a slight crosswind.

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Guest NormanB

Mike,As always thanks for your input, as indeed everybody else. Whilst I don't reply to every post it is all noted and passed to those who do the fixing.Jeff, you can't seriously suggest we would want somebody who insists on sharing a nickname with a 'roo? ;)Chris, despite your love of antipodean marsupials, your points have been added to a similar list we have internally and when I get a moment will ammend the sticky post.

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Guest FlyinJ

Norman - Do you mean as in "skippy to the roo my darling"? :-lol -Jeffp.s. Sorry Chris! No offense! :)

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Hello,the reference message bears a respectable signature, I'd like to comment about the stated real world practices as I know and teach them:1. In smaller aircraft with poor directional control characteristics (e.g Cessna 206), you certainly would use the runway width to overcome cross wind during runway operations, for the mere reason of safest practice.2. With aircraft approved for operation under contemporary regulation, during crosswind landing you use bank while keeping the longitudinal axis with the runway to counter crosswind and maintain runway centerline till full touchdown. Aircraft wind limitations account for all aircraft characteristics, (with a substantial safety margin to account for below average piloting technique) including engine mount and size. Banking is similarly used during crosswind liftoff to prevent sideward motion. This bank is retained to turn into wind when runway centerline needs to be maintained.3. The best technique to counter crosswind for the flare and touchdown phase, in aircraft holding constant speed during the final apporach (not rotorcraft), is to align the aircraft with runway centerline using the yaw axis when crossing runway threshold, while maintaining runway center with bank till all main undercarriages touch down. Any other technique leads to wheel tires slipping sideways.Based on extensive experience in experimental flight test.>You don't land on any side, you aim for the center>line...crosswind, no wind, headwind, hail, act of god, deer on>the runway, etc... center line.>>Second, you don't want a few degrees of bank in an aircraft>with wing mounted engines because you then run the risk of>using your GE-90s as sleds. Sometimes it can't be helped but>trust me it is seldom on purpose. >>Third, you don't kick out once the wheels are down, you kick>out just BEFORE the wheels are down. Otherwise you will>eventually overstress the gear and find that you are taxiing>to the gate on your belly.>>Fourth, I am having the same yaw problem too. Once I touch>down with any amount of yaw I start sliding towards the>opposite side from where the wind is blowing. This is made>worse since I am trying to disconnect the autopilot, autobrake>and autothrottles because they won't disconnect themselves as>they are supposed to so I find myself fighting the T7 all the>way down the runway, taking out runway lights and unsuspecting>groundskeepers mowing the grass as I struggle by.>>Similarly I am also havin the autopilot issue. Bank>oscillations all the way down the glideslope (not as severe>now I turned down my realism setting (argh!!!)). Still once>on the ground unless I disengage the AP I'm certain to start>heading towards the grass with even a slight crosswind.


Regards, Opher Ben Peretz

KLMMD-11.jpg

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Whilst waiting for the patch, I have been experimenting further with the current standard. I found that whilst the LOC light goes out on touchdown, I can immediately reselect it. The autopilot then appears to react to the localisor BUT it only uses the ailerons/spoilers to try and control the yaw. On three landings with 8

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Nice observations John. 1. Aileron inputs are used to prevent sideward drift, with counter-crosswind roll moments. Their use for directional control low above or on the runway is non-standard , with unpredictable outcome.2. Piloting is an acquired skill, which needs extensive training for both qualification and proficiency retention.3. Landing is the most critical piloting maneuver in transport category aircraft.


Regards, Opher Ben Peretz

KLMMD-11.jpg

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Opher,Agree - afraid 30 years on jet fighters doesn't quite prepare you for a 777 - I can remember one which required full aileron after touchdown when landing on the xwnd limits. Still its a very interesting discussion whilst we await the patch.John R

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Guest FlyinJ

John, Opher,In every single engine aircraft I have ever flown (Cessna, Piper, Cirrus), it has always been standard practice during the takeoff roll or after landing to maintain centerline with rudder and keep the control column (hence, the ailerons) turned into the crosswind to avoid an unexpected 'excursion' due to a gust of wind. Naturally, as speed increases during the takoff roll, the amount of aileron input is decreased and vice-versa for the landing roll as speed decreases.I would imagine this technique also applies to the 'big iron' as well.Jeff

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Jeff,take the Cessna 206 as example (with or without Robertson wing enhancement), real world:The aircraft, more noticeably the variant with the belly cargo hull, has substantial side area, which during cross wind takeoff and landing results in a large sideforce, which pushes the aircraft sideways off the runway. The nosewheel steering is unable to overcome that sideforce due to insufficient control characteristics, both early in the takeoff roll, and after lowering the nosewheel during landing. Similary, neither the rudder nor the ailerons are effective enough to generate sufficient yaw and roll to avoid the aircraft going off the runway, all this within FAA approved crosswind limitations. One operating approach could limit the crosswind flight envelope of the aircraft. Another, especially useful when but not only on a remote flight strip in the middle of nowhere, nobody nearby, sunset on the horizon. Runway width is not a decoration, you use it. I have flown as pilot in command 90 aircraft types, in varying operating conditions, facing odd problems. Adapting flying technique to the situation is an effective approach to safe flying, used by successful organizations, not just improvisers.


Regards, Opher Ben Peretz

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Guest FlyinJ

Good points all, Opher.J

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Guest RichR

For general knowledge, during an auto land when does the nose wheel steering become effective as the control surface forces diminish?What controls the nose wheel steering as the A/C slows down? The reason I ask is all ground handling of the 777 is difficult if the ground speed is over 10Kts. The A/C just skids if the speed is too high. If this is the case during an auto land, I can understand the loss of control if some side force such as a cross wind is present. I have checked a few landings with the playback feature and have noted a slight deflection of the nose wheel during the roll out even though the A/C was on the center line at the time.Maybe I'm missing something. A paper on Auto Landings such as the Auto Throttle usage could be helpful.RichR

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