Crosswind landing question

[Mikeingreen 139]

I just finished watching the Discovery series Flying Wild Alaska, which I found fascinating, especially the croswind stuff. I understand why they try to land one wheel first but I am not sure which wheel. I am guessing that if the wind is blowing right to left you try to settle on the left gear first to keep from flipping over to the left. I can also imagine it would be right gear first to keep the aircraft tilted into the wind. Which is correct?

On a side note, the pilots in that show are insane.

[Overload 91]

You land on the into wind wheel first. Typically you are "crabbing" on approach, keeping the nose just enough into wind to keep the aircraft tracking the centre line, so if the wind is right to left, you'd have the nose pointing right of the runway to maintain the centre line, once over the threshold, use the (left in this case) rudder to straighten the aircraft and line up with the centreline. If you then kept the wings level, because the wind is blowing from the right, the aircraft would start drifting sideways towards the left edge of the runway, so you turn the yoke a little to the right (the greater the crosswind, the greater the into wind aileron), lowering the right wing, this stops the drift, but is why the right wheel would touch down first. 

I've found this technique works well in MSFS, and I can cope with really hefty crosswinds. The aircraft can be a little "squirrelly" on the ground as the rudder loses effectiveness as the aircraft slows, holding full into wind aileron after touchdown helps. 

[G550flyer 1,013]

Yep, the wheel touch is just a by product of your landing as you lean into the wind. I am a big wing low method fan. I like to get my hands and legs warmed up around 200 to 300ft so I get a feel of what my crosswind controls will be like.

[psolk 3,040]

1 hour ago, Overload said:

You land on the into wind wheel first. Typically you are "crabbing" on approach, keeping the nose just enough into wind to keep the aircraft tracking the centre line, so if the wind is right to left, you'd have the nose pointing right of the runway to maintain the centre line, once over the threshold, use the (left in this case) rudder to straighten the aircraft and line up with the centreline. If you then kept the wings level, because the wind is blowing from the right, the aircraft would start drifting sideways towards the left edge of the runway, so you turn the yoke a little to the right (the greater the crosswind, the greater the into wind aileron), lowering the right wing, this stops the drift, but is why the right wheel would touch down first. 

I've found this technique works well in MSFS, and I can cope with really hefty crosswinds. The aircraft can be a little "squirrelly" on the ground as the rudder loses effectiveness as the aircraft slows, holding full into wind aileron after touchdown helps. 

I've always done this as well unless I'm in a smaller GA bird... 

My understanding has always been in a large jet  you want to stay away from large rudder deflections (thinking of the AA flight that crashed in NY) and in GA your legs should be tired after the flight LOL. 

Is the rudder heavily used on a commercial jet while crabbing or is it a last minute flick?  Always wondered this and if I was doing it correctly.  Probably not LOL  

[G550flyer 1,013]

3 minutes ago, psolk said:

Is the rudder heavily used on a commercial jet while crabbing or is it a last minute flick?  Always wondered this and if I was doing it correctly.  Probably not LOL  

It all depends. I'm old school and have always used wing low in heavies. When I flew DC10s, you had to use a lot of rudder in crosswinds, it weather vanes easily. With a good 28 to 30kt crosswind, you have A LOT of rudder input in. During recurrents in the sim, you got a workout on engine out approaches and go arounds. Those big cans under the wings put out a lot of thrust on the go and you would be shaking from rudder input after a couple wing single engine gos. If they are nice, they will leave you with the tail engine which was a no brainer. I have flown with some guys who have said that wing low can't be done in jets with low wing engine ground clearance. Maybe like a 737 that already has the engine adjusted at the bottom for ground clearance. I love the wing low method because I can sync and drift kill my cross controls early on. In the flare I'm only thinking of the sight picture and the call out cadence. I can imagine doing the kick in the flare my lead to some rudder dance as you try to feel input for alignment and work your sight picture. I have had some peeps touch down in a crab before and did not like the way the jet snapped and how quickly the runway edge approached. Would be nice if all jets had that crosswind crab system that the B52 has. Weird, but it works like a charm.

Rick 

[psolk 3,040]

5 minutes ago, G550flyer said:

It all depends. I'm old school and have always used wing low in heavies. When I flew DC10s, you had to use a lot of rudder in crosswinds, it weather vanes easily. With a good 28 to 30kt crosswind, you have A LOT of rudder input in. During recurrents in the sim, you got a workout on engine out approaches and go arounds. Those big cans under the wings put out a lot of thrust on the go and you would be shaking from rudder input after a couple wing single engine gos. If they are nice, they will leave you with the tail engine which was a no brainer. I have flown with some guys who have said that wing low can't be done in jets with low wing engine ground clearance. Maybe like a 737 that already has the engine adjusted at the bottom for ground clearance. I love the wing low method because I can sync and drift kill my cross controls early on. In the flare I'm only thinking of the sight picture and the call out cadence. I can imagine doing the kick in the flare my lead to some rudder dance as you try to feel input for alignment and work your sight picture. I have had some peeps touch down in a crab before and did not like the way the jet snapped and how quickly the runway edge approached. Would be nice if all jets had that crosswind crab system that the B52 has. Weird, but it works like a charm.

Rick 

Great information, than you for sharing Rick!  So I shouldn't be scared to give it some input even in a 777/787 with a stiff crosswind!  I can relate to the leg shaking, I've experienced that in the race car when you spend too much time trying to put the pedals through the floor to magically go faster or stop quicker LOL. My coach always reminds me pressing the pedals harder only works "to a point" 🙂  

[G550flyer 1,013]

20 minutes ago, psolk said:

Great information, than you for sharing Rick!  So I shouldn't be scared to give it some input even in a 777/787 with a stiff crosswind!  I can relate to the leg shaking, I've experienced that in the race car when you spend too much time trying to put the pedals through the floor to magically go faster or stop quicker LOL. My coach always reminds me pressing the pedals harder only works "to a point" 🙂  

No Sir, just point the nose down centerline on short final and use roll control to move left and right. Pedal to the floor unlocks the secret option lol.

Rick

[188AHC 2,138]

Right right. Left left as stated

 I've landed in some pretty strong crosswinds and my first serious crosswind in a C-150 scared the stuffing out of me. Landed almost sideways but some left rudder at td cleaned it up. Also remember to keep your upwind wing down slightly so you don't end topside down. 

Thank you for a posting a great aviation related topic in Hangar Chat. 

This is the kind if stuff I appreciate in this forum. 

[Chock 17,769]

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18 hours ago, Mikeingreen said:

I just finished watching the Discovery series Flying Wild Alaska, which I found fascinating, especially the croswind stuff. I understand why they try to land one wheel first but I am not sure which wheel. I am guessing that if the wind is blowing right to left you try to settle on the left gear first to keep from flipping over to the left. I can also imagine it would be right gear first to keep the aircraft tilted into the wind. Which is correct?

On a side note, the pilots in that show are insane.

As you've surmised, you touch down on the wheel which is into the wind, but really this is just a function of the fact that the aeroplane is banked over leaning into the wind to counter the drift, so inevitably, one wheel will touch before the other one.

Technically, there are two ways to do a crosswind landing, these being the 'cross-control, aka wing-low method' where you essentially fly down toward the runway centreline, but lean the aeroplane into the wind by banking it into the direction of the wind, then use opposite rudder to keep it tracking straight when you have it in the sweet spot, which is basically a sideslip maneuver. The other is the 'crab' method, which is where you essentially stay wings-level, but point the aeroplane into the wind by several degrees to counter the wind drift, meaning come down at the runway slightly 'sideways', then you kick the thing straight just before touchdown.

Which method you would use is somewhat dependent on preference, but also on the type of aeroplane you are flying. In reality, I think it is fair to say that quite a lot of pilots sort of mix and match these two methods a bit as the situation calls for it, rather than only doing one or the other.

Things to consider with regard to these methods are the sweep of the wings (very well swept back wings will get near the ground on a landing flare if you are banked over), the dihedral angle of the wings (a large dihedral angle gives you a lot of extra clearance), the proximity of modern split scimitar winglets to the ground (these can get really near the ground on a swept-wing aeroplane if it is banked over and flared), and the proximity of any underslung engine pods on the wings (some aeroplanes, such as the 737 NG, have these quite close to the ground as it is, so you have to be careful). The crab method largely eliminates the risk of any of these features of an aeroplane getting too close to the ground since you are wings-level with that technique, but you do have to make sure you kick the thing straight before touching down or you can put too much sideways force on the landing gear. But with care and consideration for these potential factors, this does not mean the wing down technique cannot be used on an aeroplane with some of those physical characteristics, so long as one is aware of it all and the limits they impart.

One interesting thing which a lot of people are unaware of in all this malarkey, is the fact that quite a few airliners - the A320 Airbus for example - have a system which limits the amount of aileron input you can make the moment the wheels touch the ground. This triggers via a weight on the wheels sensor in the undercarriage which detects that the undercarriage oleos have compressed. What this system typically does, is halves the maximum throw you can put into the ailerons when the plane touches down, in order to prevent an accidentally excessive input near the ground during a crosswind landing which might cause an engine pod strike. This means you'd need to be aware that if you were using the wing-down technique in gusty conditions, you might have to be ready to really shove the stick over the opposite way to counter a gust which threatened to cause a wingtip or pod strike, because your ailerons are going to be limited in what they can do.

Another thing to be aware of, is wind gradient. Typically the headwind and crosswind components your aeroplane will encounter during a landing will drop off a bit as you get nearer the runway. This is because as the wind blows over the landscape, it encounters drag from the terrain, but as you get higher up, there is less drag from this. What this means is that crosswinds and headwinds often lessen as you descend toward the runway, but they can also shift around a bit as the wind blows over and around structures and hills etc. This is of course why we always land at a speed well above the stall speed, to give us a margin of safety from a decreasing headwind component, but it also means that picking a bank angle or crab angle for a crosswind landing is rarely a 'set it and forget it' type of deal, but rather something you have to adjust as you descend.

If all of this stuff sounds tricky, it's as well to be aware that most of it is fairly dynamic and intuitive in real life if you are a half-decent pilot who knows what the controls do, because on a real aeroplane you have far more feedback than you do on a flight sim, so don't worry too much if you find you are not instantly brilliant at crosswind landings on a flight sim, because sat at a desk rather than being bounced around in a cockpit with a wide field of view, you are missing a lot of the clues you get when doing it on the real thing.

Edited March 12, 2022 by Chock

[Overload 91]

Back in the olden days (1970's), I was an instructor at a flying club based at EGBB, Birmingham UK. The prevailing wind  in the UK is Southwest to West, so with the main runway 15/33 there was a lot of opportunity to practice crosswind landings. 

I developed an instructional technique that worked rather well. For the 1st couple of circuits I would control the ailerons, with the student controlling the rudders. I favoured the crab - kick it straight - drop a wing method, so on crossing the threshold the students only job was to use the rudder to keep the nose lined up with the centre line, I'd used bank to slip as required to maintain the centre line. The students pretty much all kicked it straight fine, but then would not realise more rudder was needed as rudder effectiveness reduced, less if the wind dropped - it was a constant dance on the pedals to keep it straight. The runway was 7500 long, and a C150/PA28 would float forever with around 1700 RPM, loads of time to practice the skill.

After 2 or 3 of these circuits, we'd switch, I'd keep it straight with the rudder, they'd use into wind aileron to maintain the centre line, they usually found that a little trickier, but learnt it's a constantly changing amount of bank, just like it was with the rudder, and with a float lasting forever, had loads of time to get it together.

Then finally they'd do the whole thing, and marry the 2 components together, and most of them finished with a much better understanding of what they were trying to achieve. On most days - except flat calm, those cross wind skills are needed to a greater or lessor amount, so a good understanding of the technique should improve any landing.

[Mikeingreen 139]

Thanks to you all for the answers. That cleared it up for me, now just to put it to use. 

[Fielder 3,662]

I wonder if anyone posted this (happened a month ago), 35-40 knot winds at Heathrow.. Airbus of some type...

 

[n4gix 4,947]

Just a little runway rash. That should buff right out. /s