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Guest venquessa

X wind landing Q.

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Something I have neglected to practice in simming that much is getting the plane straightened up when touching down in a strong X wind.I was thinking about this a bit and here's what I came up with.On approach you might have a 5 or 10 offest from center line due to wind. Landing like that is probably not good for the gear, certainly it will wear the tyres badly, possibly flat spotting them, which give vibration and they need replaced. If you land heavy and remember "grip" is directly related to force on the contact area of rubber (from driving sims :D), the plane may even attempt to roll up on you. You could even bust the gear off in the extreme or slap a wing tip into the deck.So I thought that, hitting the rudder hard over just in the flare to get the wheels track straight for touch down then straighting up to hold the plane straight would be the correct thing to do.However there are a number problems when you try this.1. The A/P doesn't like it. It will go to CWS wont it? That will then make you in control of the flare as well.2. If you straighten up even a second before touch down, then the plane will still be flying sideways across the runway, aided by the wind, so the wheel will still have lateral velocity on touch down.3. Because of 2 you tend to float across the runway. If the A/P is doing its job you should be on the centerline, yet when you straighten up a good 20knot X wind can blow you off the runwway, or at least well off the center line.So, I would suspect that either landing in up to the A/P rated X wind without straightening up in acceptable, or you have to fly the last few hundred feet down by hand, move over the up wind side of the runway, so that when you flare and straighten the wind has blown you back onto center line.Any thoughts advice of the real procedures?Thanks.PS. I have been attempting to find my limits (and the NGs) with wind. I managed to land, heavily but "ok'ish" in a 0 knot wind, with gusts at 70knots. It's not easy, you have stay fast and keep pushing her down into the gusts as she tries to soar. Then idle and float down the runway, remembering to almost literally force her down, if you let it float down to VREF (with no wind correction added), when the gust drops you stall and hit the tarmac hard.A 0 gusting 140 wind, was too much though and resulted in the plane being slammed into the tarmac at about 0 IAS.

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I wouldn't worry about the tires that much. They're replaced I don't know how many times. I've once flown on a CO 757 that was landing in a crosswing, and the pilot was crabbing it to where I could almost see the runway. When we touched down, he quickly turned it to the centerline with the rudder and you could feel a quick jolt along with some tire screeching. I think the tires can handle something like that, especially since they're replaced so often.Nick B.Continental Airlines Virtual 737NG Pilothttp://www.precisionmanuals.com/images/forum/800driver.jpg--AMD Athlon XP 3200+ @ 2.2 Ghz (Equal to 2.8 ghz)400W Power supply3x 80 mm Case FansSoyo VIA KT600 Dragon PlusnVidia GeForce FX 5200 128 mb2 x 512 PC400100 GB Western DigitalMicrosoft Sidewinder Precision 2

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"So I thought that, hitting the rudder hard over just in the flare to get the wheels track straight for touch down then straighting up to hold the plane straight would be the correct thing to do.1. The A/P doesn't like it. It will go to CWS wont it? That will then make you in control of the flare as well." No since rudder is not control colume."...If the A/P is doing its job you should be on the centerline, yet when you straighten up a good 20knot X wind can blow you off the runwway, or at least well off the center line." Well once on the ground there is no centerline guidence on the RW NG or this aircraft. You MUST manually disconnect the A/P atfer T/D. Well I think if the wind is going good maybe one should be manually flying it down. Don't really know, good question for Brad Marsh though ;-)... Best Wishes,[h4]Randy J. Smith[/h4][h3]P M D G's 747-400[/h3][h4]coming to a runway near you[/h4][/font color]Caution! Not a real pilot, but do play one on TV ;-)AMD 64 3200+ | ASUS KV8 DELUXE | GFORCE 5700 ULTRA @535/1000 | Maxtor 6Y080M0 SATA 80 GIG | 512 DDR 400 | Windows Xp Pro | Windows Xp Pro 64 |

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Just some thoughts (guesses).As you know there are specific limits when it comes to allowable x-wind. I

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I don't know if this will help with PDMG (I'm new to the PDMG simulation), but there are 2 normal procedures when landing in a crosswind in a small plane. Which one you use is mostly dependent on pilot's preference & comfort.The first procedure is to 'crab' the airplane until just before the flare. As you are ready to flare, you kick in the rudder & straighten the nose so that it is aligned with the runway. The trick here is to also lower the upwind wing at the same time so that the plane does not start turning. Depending on the strength of the crosswind, you may end up touching down on one wheel first & then lowering the other wheel.The second procedure is to maintain a forward slip on the approach, meaning you keep the upwind wing low while simultaneously keeping the nose straight & aligned with the runway all the way to touch-down (also likely on one wheel). I found this method more tricky in real life than my preferred crabbing approach when I used to fly Cessna's.Note that in both procedures the controls are crossed (right rudder - left aileron or left rudder - right aileron)

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>>The second procedure is to maintain a forward slip on the>approach, meaning you keep the upwind wing low while>simultaneously keeping the nose straight & aligned with the>runway all the way to touch-down (also likely on one wheel). I>found this method more tricky in real life than my preferred>crabbing approach when I used to fly Cessna's.>That's actually a "sideslip" or "wing low" approach. In the forward slip the plane is yawed away from the direction of movement ... in the sideslip on the other the plane's longitudinal axis is aligned with the direction of movement ... the plane is just banked.there's 2 problems that I know of with crabbing with an airliner:1 - airline companies for what I know, have rules against using it because it makes passengers mighty uncomfy and nervous. 2 - (and this might be more important) the engines in most common airliners are hanging down from under the wing. A wing low touch down might very well bend the wing to the point of having an engine strike. Single engine planes don't have the same problem, especially high wing planes. These is just what I heard ... I don't know for sure and I don't have material to back this up, so I may be wrong ...

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I stand corrected about the term I used :-). You are quite right about it being a sideslip rather than a forward slip. For your other point however, I don't think you are quire right about what the airliners do. I go & watch airliners landing at the Toronto airport quite often, & whenever there is a crosswind, they always crab during the approach whenever I have watched them (& in some cases, rather severe crabbing).It would be interesting to hear from an airline captain to see what they are told to do. If they are told not to crab, then most of them are ignoring this (at least in the Toronto airport) as far as I can see.As far as landing on one wheel is concerned, I believe this is the only way to avoid drifting during the actual landing and I have seen many airliners touch down on one wheel as well. It does does not have to be a really low wing touchdown, just low enough to prevent the drift.Comments from airline pilots would be be very appreciated.Thanks

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>I stand corrected about the term I used :-). You are quite>right about it being a sideslip rather than a forward slip.>For your other point however, I don't think you are quire>right about what the airliners do. Ok. I am dumb. I mis-typed what I wanted to say.I typed:"there's 2 problems that I know of with crabbing with an airliner:"Wrong. What I meant to type instead is:"there's 2 problems that I know of with SIDE-SLIPPING with an airliner:"Airliners SHOULD crab and SHOULD NOT side-slip (again, to the limit of the my knowledge).Sorry for the confusion. Doh.

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Is the side-slip approach what I've heard referred to as a cross-coordinated approach?I personally tend to fly my approach crabbed until about 2nm out when I rudder out of the wind and add a touch of bank into the wind. The only reason I do this is when I'm hand flying it's a little easier for me to tell where I am in relation to the centerline and make any minute last minute corrections. This may be incorrect though; I only do it because I always flew smaller props cross-coordinated for xwind landings when I was learning to fly in sims.

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Real life airliners can land in a crab in a strong wind. New generation autoland systems can do 25 knots crosswind and will land in a 5 degree crab. I know there are some sites that have videos of some horrendous landings into Hong Kong. the only time any of the planes were on the centerline is when they taxied in.

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Not sure about your first question since both crabbing & sideslipping necessitate crossed controls.The reason I preferred 'crabbing' in a real Cessna was because I found that the plane almost automatically assumed the correct crab angle with only minor corrections necessary along the way. When approaching with a sideslip instead, I always found it much more difficult to remain in the runway center line. I learned to fly in a small airport with only one runway, so crosswind landings became almost natural to me at that time.I do find though that crosswind landings in a Cessna in FS is much more difficult that I recall in real life. It seems that you do not get the visual clues as quickly in the sim and I've never been able to master crosswind landings in FS.

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I dunno, I've never flown in real life. The part that was hardest for me flying a crosswind landing in FS is like you say, a visual cue, I'm never able to tell if my track is on the centerline. I attribute it to poor visual limitations imposed by a "small" monitor (relative to your actual field of view). With cross coordinating I'm able to more easily tell if I'm heading down the centerline. Best crosswind landing I ever did was crosswind of 60 knots gusting to 70 in a beach 58... I had to do that with a mix of crosscoordinating and crabbing, was just playing around, but it was a challenge.

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Actually crabbing doesn't require cross control input. All you're doing is maintaining a course by adjusting your heading for wind drift.As for a crosswind procedure, our pilots are trained to crab into the wind with no bank input during the approach. It's the procudure at the flare that takes some practice. They use the GPWS altitude calls and rad alt as reference along with how strong the crosswind is to determine a height to kick the nose straight. Anywhere from 20 ft. for a light crosswind to just before touchdown on a heavy crosswind. The trick is to kick the nose straight and keep the wings level without drifting too far off the centre line at touchdown. Done too soon and you will drift.BTW, unless the conditions warrant, the auto pilot is not used during the approach by our crews. If it is required, they disconnect at DH and hand fly to touch down. Not too many Cat II and III runways in Canada.Cheers,JohnBoeing 727/737 & Lockheed C-130/L-100 Mechanichttp://www.precisionmanuals.com/images/forum/ng_driver.jpg

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The short answers:Autopilot (autoland) --The autopilot

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Trick I used when I got my Pilots license was to try and keep touchdown spot from moving on the windshield. That way you knew that you were headed for a certain spot on the runway. Then just use the wheel for the wind and the rudder for the runway, as you are flaring.

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>I do find though that crosswind landings in a Cessna in FS is>much more difficult that I recall in real life. It seems that>you do not get the visual clues as quickly in the sim and I've>never been able to master crosswind landings in FS.No kidding!One of the things I noticed is that putting a real plane in a side slip doesn't really affect its forward momentum right away. It takes a bit for the plane to slow down and because it's in a side slip, it will drop and slow faster than if it was a straight landing.But in FS that effect is tripled to say the least. As soon as I cross the controls the plane sinks like a brick in flight sim.In real life I can float for a bit.That probably depends on the fact that in real life I crab all the way down until I see the runway threshold disappear under my nose (usually I am 10-20 feet AGL at this point) and that's pretty much when I kick the crab out and go wing low. The ground effect here helps me soften the blow, the plane slows but not as much and it doesn't sink all of a sudden (which makes the transintion relatively smooth ... if I handle it right).In FS ... there is no ground effect that I can discern.

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I'm fairly sure there is ground effect in FS2004. If you don't make the touch down "firm" in the 737 you float along the runway, even with the stick pushed forward she wants to fly! 2 seconds earlier with the throttle on it wanted to sink, so something must be happening close to the ground.I think there are a lot of different techniques being confused in this thread. As someone pointed out a normal Xwind approach doesn't require any cross controls, you simply fly a course with a wind correction angle to hold the centerline.Side slipping I thought was used for losing height without lossing that much speed and being able to keep the throttle open when doing so meaning you can come out of it quickly, for example in a small plane diving for the deck due to being higher than wanted on approach. Half rudder and half aleron will slow you down a bit and cause you to sink quickly, in roughly a straight line, just with the aircraft sitting sideways. This is not the same as flying a wind correction angle landing. I think someone said, this is NOT done in an airliner and I can imagine what it would feel like in the back! My stomach tells me it would not enjoy the manouver.Sorry for delibrately avoiding the correct terms, but a) I think it's these that are causing confusion and :( I am not sure enough about them to use them correctly.The "kick it straight and drop the wind side wing" idea. I'm not sure I can run that through the grey matter visualizer (my brain) and get the correct results. If you kick it straight you will drift. If you then drop the wind side wing, you will drift more (and probably sink faster) as you have exposed more (upper) wing surface to the wind. You should start to turn into the wind though which brings us back to a wind correction angle. If you counter that with the rudder, we are into a sideslip sink then. So I'm confused with this.Thanks for the discussion, very interesting. :)

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"If you kick it straight you will drift. "I think the point he was trying to make is that if you use the rudder to kick it straight you will still retain your flight path for a little while longer (the slip), it won't be an immediate change of flight path, but it will be an immediate change of yaw angle to line you up with the runway heading. The trick stated is to do it at just the right altitude, as mentioned if you do it too high you would drift.

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I know this sounded a bit confusing about using crossed controls in a crab. I did not really mean during the crabbing period, but simply when getting out of the crab.When I kick in the rudder in the opposite direction of the crab angle & straighten the plane so that the nose is pointed in the direction of the center line, the plane would start drifting if I did not at the same time lower the upwind wing to avoid drifting.An example may make it clearer. If the wind is coming from the left side, the nose would be pointed left of the center line during the crabbing approach (wings level). As I reached the numbers, I would kick in the right rudder just enough to center the nose. This would normally cause a drift to the right if I did not at the same time lower the left wing to cancel the drifting motion. This is when the controls are 'crossed' & the side slip occurs rather than during the crabbing glide.Hope this makes it a bit clearer :-)

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>I'm fairly sure there is ground effect in FS2004. >I don't know what to tell you. I tried to do soft-field take offs in the Cessna in FS and the plane just doesn't take off.Translation: in soft field takeoffs you (supposedly) take off from rough fields (dirt or grass) and you want to get the plane away from the runway surface ASAP. In order to do this you exploit ground effect.During the take off you pull the yoke and keep it pulled during the takeoff roll, with about 10 deg of flaps down.The plane will prematurely come off the ground (because it's in ground effect) and because of that it will not stall but it will behave normally even if the airborne speed is very slow an below stall speed.If you let it climb too much out of ground effect the plane will indeed stall and fall back on the runway and then you need to deal with Advil and Insurance Deductibles. So to avoid that you bring the nose down, and let the plane fly parallel to the runway surface, about 5-10 feet above the runway for about 5 seconds, letting the plane pick up speed in ground effect, then as soon as you hit Vx (best angle of climb speed) you bring the nose up and the plane literally shoots up from under your ####. That's Real Life.In flight sim, I tried to do this and the plane would just start screaming stall as soon as the wheels come off the ground and then it will stay stalled and not fly. Even a few feet off the runway.I remember trying it in FS2002 first and then being disappointed when I tried in FS2004 (the first day I got it) and finding out that it wasn't modelled in there either. So my guess is that either ground effect is not modelled or it's not modelled completely. So I really don't know what the answer is about ground effect in FS.>I think there are a lot of different techniques being confused>in this thread. As someone pointed out a normal Xwind>approach doesn't require any cross controls, you simply fly a>course with a wind correction angle to hold the centerline.>>Side slipping I thought was used for losing height without>lossing that much speed and being able to keep the throttle>open when doing so meaning you can come out of it quickly, for>example in a small plane diving for the deck due to being>higher than wanted on approach. Half rudder and half aleron>will slow you down a bit and cause you to sink quickly, in>roughly a straight line, just with the aircraft sitting>sideways. This is not the same as flying a wind correction>angle landing. There's two slips:1 - forward slip: its purpose is to lose altitude without gaining speed. You cut power, turn the yoke all the way to one side and push the opposite rudder all the way in and then pull the yoke towards you to slow the plane down. So if you bank the plane to the right you push the rudder to the left for example.That's what I do if I need to bleed a lot of altitude at 2000 feet per NY minute. I like to keep my speed around 80-90 knots depending on the plane and the loading. Any faster and some planes start to buffet ... and slower and the plane is too close to a stall for my comfort.Cessnas like to forward slip a lot more than Pipers ... my Piper is a pain in the #### to forward slip.While you forward slip the longitudinal axis of the plane is NOT aligned with your direction of movement. In other words, in order to look staright at where you are going you have to look out your side window ... literally. and then 2 - Sideslip: it's similar to forward slip in that you keep your controls crossed but you don't fly from one side. You fly straight down your nose ... with the plane longitudinal axis aligned with your direction of movement ... and it's the wind that is keeping you aligned. >>The "kick it straight and drop the wind side wing" idea. I'm>not sure I can run that through the grey matter visualizer (my>brain) and get the correct results. If you kick it straight>you will drift. If you then drop the wind side wing, you will>drift more No you won't, because you will lower the wings AGAINST the wind. This means that your lift vector will be pointing towards the wind and there's gong to be a "horizontal" component of your lift vector that will pull you laterally against the wind. The stronger the wing the deeper the bank you have to use. I hope this is not killing you because Vectors and such are indeed complicated to understand and visualize if you haven't studied them a little bit deeper. It's that lateral component of lift countered by the wind that is keeping the plane flying straight as opposed to the forward slip.>(and probably sink faster) as you have exposed more>(upper) wing surface to the wind. Yes you do sink faster but that's not the reason why.You sink faster because now your lift vector is partially spent against the wind and the vertical component just got smaller.That's when I usually apply a bit of power during the flare to slow my sink rate ... but only during the flare because the last thing I want is to prolong the float in a cross wind. The less I need to keep flying with my controls corssed the better I feel.Here's where ground effect helps a bit by softening your initial sink rate.Keeping the plane aligned with the centerline with control crossed in variable winds or even in wind shear is not exactly my idea of an entertaining flight ... so that's why I go wing low right before I pass the threshold (as someone else in this thread mentioned)>You should start to turn>into the wind though which brings us back to a wind correction>angle. If you counter that with the rudder, we are into a>sideslip sink then. So I'm confused with this.No you don't need to do that. As you are using your lift vector against the wind you are now using your rudder to keep yourself aligned.In other words you change your "lateral" position in respect of the runway with your bank angle (you bank more or less to keep the plane flying along the centerline).You will use the rudder to keep the nose straight aligned with the centerline, not to crab and not to counter the wind. Don't feel bad: it is hard to understand and some real life pilots even with many many hours, better pilots than me, still have problems with this (including me). >>Thanks for the discussion, very interesting. :)I can tell you this: I landed in real life with a 25 gusty to 32 knots wind.It was NOT fun. In fact at the end of that landing I had to stop out of a taxiway and I had to wait 2 minutes because my hands were shaking and my knees were hurting and I was drenched in sweat. And it was in the middle of winter.I landed on the centerline but I had to fight the plane all the way to a stop. The sucker (it was a Skyhawk SP) wouldn't stop bucking even with all three wheels on the runway. I then went home and tried on FS2004.I couldn't do it. I just couldn't. As soon as you cross the controls the plane becomes uncontrollable and sinks like a brick (compared to real life). It will try to turn and drift on you no matter what you do with your rudder. There's just something missing in the modelling of the phisics in this case. Either that or the "feeling" of flying in a simulator is just lacking so much in terms of "situational awareness" that I can't correct my mistakes in time in FS ... I don't know what to tell ya.

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If there is ground effect in FS2004 which I doubt it sure isn't like real life. You get a Piper Warrior or Archer about 10 knots over optimum approach speed and level out in the flare and it will take what seems like an eternity for it to bleed off enough lift to land. This doesn't happen in the sim. Bob K.

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I understand the lift,drag,thrust.. em, ah, wwight (acceleration due to gravity) elements of flight, I was quite good at phyisics, I was confused by the terms applied and I believe at least one person used the term incorrectly.I understanad what you are saying about using the lift against the wind. It just made me think about what happens when you bank up steeply to turn across the wind. Trying this in a cessna in FS with a steady 40kt headwind is entertaining. You just can't have enough height, but it does make you go "YeeHa!"OK, i've had enough reality, I'm off to try and do a take off, climb, roll and split S to landing in the 737, anyone wanna take bets on how many times I have to change my undercarrage and how many time the PNF has to change his underwear?My other favourite, though not in the 737 is to take off, climb vertical to 180 stall turn, shutdown the engine, and try and land it, back on the runway. Way cool when you pull it off.

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Well, I have determined that split S to landing is as near to impossible.Below 200kts it's takes thousands of feet to roll it.As to pulling out of a loop and land. No way. LOL It just picks up way too much speed, even if it didn't it's a pig to manovuer at low speed.

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