Crosswinds

[HelenD]

What does everyone feel the best method for a PPL student or low hours PPL to use? I have been formally taught the wing down approach but think I used to instinctivly kick the rudder in. I need more practice to decide which I prefer though unless there is an overwhelming vote for one method or another.

[Aussie Andy]

G'day HelenD,

They taught crabbing rather than wing-down at BAFC in Wycombe where I learned, which seems to work well for most people, especially in the early stages.

However, for me personally, I now prefer a combined method i.e. crab until very very short final (i.e. over the hedge) then I convert it into wing-down. I had been having a few 'mares the other way, and this just works for me... I think its very much a matter of what works for you.

As long as you feel you're not at a stage where it will add to confusion, I'd suggest you ak your instructor to demonstrate all three methods: crab only, wing down only, and combined crab/wing-down method. Could be a fun way to spend a nice gusty afternoon :)

Hope this helps,

[distaff_beancounter]

I mostly fly low-wing singles & twins.

I always use the crab approach. It was the way I was taught (at Cabair) & seems to be the logical method to me. I think that it gives you the best assessment of the wind, 'cos you can judge the actual wind by how much crab you have got.

Just before touch down, turn ailerons into wind, & keep them there on the landing roll, to prevent the into-wind wing from lifting, & kick rudder straight.

Remember, that on your initial call to the airfield for joining, you can always request their surface wind. This gives you time to get set up for a decent approach.

Happy flying :)

[M14P]

Never Kick always PUUUUSH!

I find that it depends on aircraft type also. Some 'feel' right wing down and others do crabbing quite well. That said I only ever do the wing down bit in the late stages of finals because I feel it difficult to judge further out.

[QNH 1013]

I think it is all a question of what works best for you. I was taught the crab method but when I progressed to taildraggers I found that the wing-down method worked best (for me).
If I can, I set up wing-down as soon as I am lined up on final thus giving me the longest time to stabilise the approach.
The exeption has to be when you are flying an aircraft with wing tanks less than, say, 1/3 full. Prolonged wing-down can then lead to fuel starvation if you have the down-wing tank selected. If this is likely, the P.O.H. usually recommends crab followed by wing-down on short final.
Grass is much more forgiving for cross-wind landings than tarmac, particularly for taildraggers. Unfortunately you don't often get the choice.

[A and C]

The crab seems to be the way most low wing aicraft land best and the wing down seems to be the preferd option for the high wing aircraft .

Myself I favor the crab whatever the aircraft in the end i think that you should just do what feels good for you.

[Genghis the Engineer]

In my opinion, this comes far more down to the aircraft's characteristics than personal preference.

For example, if an aircraft has low lateral stability and good rudder power, a crabbed approach will always be preferable (for example a Zenair CH701). Similarly, an aircraft with high sideforces, such as an X'Air needs this approach, because the sideslip during wing-down is incredibly uncomfortable.

However, if lateral stability is higher, a crabbed approach can be difficult to fly because of the large attitude change during the transition to wing-down in the flare, so (particularly if the aircraft has lowish sideforce due to sideslip) a wing down is favoured. The high wing Cessna's come firmly into this bracket in my book, as do the Shadow and L1011 (now there's two aircraft types you rarely get together in one sentence).

The use of crab-only is generally reserved for aircraft without independent yaw controls, and boasting especially strengthened undercarriages. I land a flexwing microlight, or a 2-axis aeroplane (flying flea variants) like this, but would not normally contemplate that in anything else - you'll probably pull the gear off in a decent crosswind, and certainly upset the owner.

Having said that, many aircraft are "in the middle" with regard to lateral stability and rudder power, so it's reasonably to pick which one you're most comfortable. but, the POH for the type should give you guidance, and I'd recommend starting with that at-least. Mind you, I just got a PA28 manual off the shelf, which offers no advice at-all, although my experience is that wing-down works best on that type because the sideforces are so low.

G

[Monocock]

QNH 1013..........

Nice point.

Never thought of it like that and I fly a high wing.....scary thought.

[FlyingForFun]

I think it mainly depends on aircraft type.

The Europa monowheel really wants to be landed using the crab method - it's single main wheel is in the centre of the aircraft, and if you land wing-down, you'll land with the outrigger first - risk of damaging the outrigger, or groundlooping, or both.

Airliners always seem to use the crab method, too - I've heard various reasons for this, including being more comfortable for pax, and not enough clearance below under-wing engines to approach wing-low. Never heard of a definite case of fuel-starvation due to approaching wing-low, although it's certainly believable. In fact, the engine failure on G-WLAC (http://www.aaib.dtlr.gov.uk/bulletin/jun01/gwlac.htm) a couple of years ago is believed to be due to fuel starvation of this kind, although it was never proved and couldn't be repeated - and that's a high-winged aircraft!

On the other hand, with many very light single-seater or two-seater taildraggers, you'll find the accuracy needed to de-crab at the exact time needed to avoid any drift is very hard to achieve, and you're much better off with the wing-down method - de-crab a fraction of a second too early or too late, and you'll risk ground-looping.

However, I think most training aircraft would be perfectly happy with either method, or with the combined method. Therefore, get your instructor to demonstrate all three, practice all three, and decide what you like best.

Personally, I was taught the crab method, but never really got the hang of it. On my skills test, I completely screwed up a cross-wind landing. The examiner passed me, but suggested I not only get some cross-wnid practice with an instructor, but also ask the instructor to teach me the wing-down method. I did, and I found the wing-down method much easier. (I've now got to learn the crab method, though, because I've bought a share in a Europa monowheel!)

Practice, practice, practice!

FFF
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[DFC]

With the exceptions listed above, nobody lands the aircraft in the crab. Every aircraft is landed pointing down the runway with the wing into wind either down or about to go down as the aircraft touches the runway.

So, the only difference between the two methods is how early the nose of the aircraft is aligned with the runway centerline.

In the "crab" method, this is in the flare and in the "wing low" method this is some time before this.

Students (and PPLs) can often have hard enough of a time getting the flare right. Adding in the transition from crab to wing low at this critical time can produce overload.

Word of Warning. When flying wing low the ball is way out to one side. If you get slow and stall, the aircraft will spin. Flying with the ball way out to one side causes extra drag. Thus in order to prevent speed decreasing, one needs to used an increased power setting.

The above warning is something to be aware of. So if flying wing down, add a knot or two and dont reduce the power too early.

My recomendation is to set up the aircraft on final approach not below 500ft crabbing into wind. At say 300ft, adopt the wing down method and fly the aircraft down to the flare. Remember that as power is reduced, speed will decrease more rapidly than normal and with this decrease in speed comes a requirement to increase control deflection in order to keep straight.

As experience and confidence increases, move the point at which the changeover occurs closer and closer until you are making the changover in the flare.

Personally, I still fly wing low from about 200ft because I find it easier.......if the rudder isnt enough to keep you straight then there is no point in landing because you will end up running off the edge. :)

DFC

[D Beaver]

I find the crabbed approach followed by transition to wing down in the flare works very well for me in the Bellanca Scout towplane right up to the cross-wind limits (15 kt).

I also use the same method in 172, although Genghis comments about lateral stability and pitch changes have got me thinking. I'll have to have a look at that next time I fly a 172.

I agree with others comments that the wing down approach is not comfortable for passengers.

[G SXTY]

As another low hours student (C152), I’d say to use whatever works.

In the very early stages I tended to crab all the way in, straightening up in the flare – although as already mentioned, this can give you an awful lot of work to do in the last few seconds of flight. Combined with lack of experience, this makes for - ahem - interesting touch downs. :o

Now with a little more experience (around 30 hours) I find myself subconsciously using wing down until the last 100’ or so, then a combination of aileron & rudder to keep wings level along the centre line. This seems to produce consistently acceptable landings, if not exactly greasers.

Don’t be too worried if it doesn’t all come together straight away – technique will certainly develop with practice. (I vividly remember my first ever approach – crosswind, naturally – and wondering why we weren’t flying towards the runway, even though I was pointing the nose straight at it). :D

[alphaalpha]

GFC's post was very interesting, but I would like to comment on one point he made, ie:

'Personally, I still fly wing low from about 200ft because I find it easier.......if the rudder isnt enough to keep you straight then there is no point in landing because you will end up running off the edge.'

The wind (and the crosswind) is often a lot stronger at 200ft agl than at 20ft. I have often been surprised at the amount of drift correction needed at 200ft or so which have lead to a reasonable landing, well within the authority of the rudder, due to reduction in wind strength and change of direction close to the ground.

I therefore try to make my decision to land or go around as late (low) as is safe when the crosswind is strong. This decision often depends on how gusty the day is as well as the usual factors like currency, type of aircraft etc.

Regards

[Wee Weasley Welshman]

Crab.

For people aspiring to a career Crab is what you will need later in your career and trust me a B737 is just the same as a PA28 in that respect.

Crab is generally easier and safer in my opinion. The issue of stall leading to spin with wing down is very valid.

Crab is how the large FTO's teach.

With good students I like to teach both techniques and see which they are best at. With not so able students I stick to crab.

WWW

[Chuck Ellsworth]

You guys are losing me here.

I am having difficulty understanding how you can go from a side slip into a spin during a landing approach.

Please enlighten me.

Cat Driver:

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:D The hardest thing about flying is knowing when to say no.:D

[Tinstaafl]

I generally prefer a combination: crab for final then somewhere around flare height change to wing down.

In some particularly gusty/strong winds the a/c I fly (an Islander :rolleyes: ) is incapable of being rolled fast enough to vary the sideslip to stay over a particular point, and is also too slug-like to be yawed fast enough for a standard crabbed landing. When conditions are like this I leave the yaw until an instant before touchdown then used maximum rudder authority + asymmetric power reduction. I still tend to want to lower the wing though...



Chuck, I think they're referring to IF the student should stall while in a sideslipped condition due to not maintaining the correct speed etc.

Not sure why increasing the speed by a knot or two as was suggested would be beneficial unless they're compensating for pitot-static errors caused by the slideslip...

[Chuck Ellsworth]

Hi Tinstaafl:

The Islander is a great bush plane.

Yeh I think I know sort of what they may be driving at, but there comes a point where common sense has to prevail or everyone will be afraid to fly.

By the way I have spent the last two weeks getting approval from your CASA to train some Aussie pilots on an airplane that they bought and re registered under Aus. Reg.

My, my, I had forgotten what a paper chase something like that can result in. For the first time in my career I have been asked to supply a copy of my personal log with three pages of proof on type.

Here in Canada there is no need to keep a personal log book ( except to show proof of time for a license or type upgrade, or instrument rating, etc. also for recency. ) Anyhow I haven't kept a personal log for many years mainly because I have never needed one. So there is always something exciting and new in Aviation.

Anyhow, eventually we will get it all straightened out. They agreed to accept an outline of my last thirty five years on type, because it is very simple to prove such flying.

Hope to get to Australia some time, the training for the type rating on the Aus. machine will be done in Europe, however I probably will get down your way eventually. Somehow I never got any closer to Australia than Fiji and Singapore.

Don't pay to much attention to some of my posts as I just get bored and have to join in once in a while.

:D :D :D

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:D The hardest thing about flying is knowing when to say no.:D

[flying snapper]

Thank you one and all for some very interesting reading.

I was practicing crosswind landing on Sunday and since then I have had this horrible feeling that I will be unable ever to master it. The reply about "giving you a lot of work on the flare" is bang on as my instructor wants me to crab until just before flare and then wing down and opposite rudder. My problem seemed to be that I did not know by how much (wing down and rudder that is!) I was fearful of touching the tarmac with wing or drifting off the tarmac completely. I also had difficulty flaring too high.

This all resulted in a depressingly bad lesson.

It was reassuring to read that many, many people are in the same situation!

[G SXTY]

Hope you were reassured then! Part of the reason for my post was to point out that in less than 30 hours, you can go from thinking its all impossible to quite acceptable crosswind landings – it will come with practice.

[Tinstaafl]

Flying snapper, if you're finding the workload a bit high when changing to wing down during the flare try changing just prior to arriving over the runway eg the undershoot area.

Also in any light a/c I can think of the wing tip is nowhere near the ground as long as you still have enough rudder input to maintain the heading ie the AoB isn't large enough. You will run out of rudder authority long before the wing is likely to scrape the runway.

Next time you're at the a/c stand some behind it. Position a ruler a ruler at arms length so that it appears to go from a mainwheel to the wingtip on that side. Now measure - or guesstimate - the angle between the ground & the ruler. It's quite large even on low wing a/c.

That angle is approximately the AoB you would need to have to scrape the wingtip.


I have heard (& seen the bodgie repair job) of a bloke scraping the wingtip in a C210 :eek: but he was a d!ckhead trying to show off by doing a one-wheel touch and go ==> lost control ==> eventually got airborne at some large angle to the runway direction after doing what was effectively a medium/steep level turn while still on the ground.

[DFC]

Chuck,

An aircraft in a sideslip (foreward slip) is flying out of balance. One can determine this by the fact that the balance ball is out to one side.

If the ball is out to one side then there is a component of yaw present.

Stall + Yaw = Spin.

When flying out of balance, extra drag is created. If power is reduced then speed will reduce quicker when out of balance then when flying in balance due to the extra drag.

If you are flying a crab approach in balance and transfer to the wing down, extra drag is created which will slow the aircraft and if the initial approach was at 1.3Vso then you can quickly find that you are below that speed at a low height with the ball way out to one side. Flying initially a few knots above 1.3 Vso should have the speed settled at 1.3Vso when the wing down is established.

DFC

[Jason2000]

I find the use of crab a lot easier than the wing down method, and that is in PA28's. I learned in the States, but now fly from Oxford, and that appears to be the prefered method here aswell.

I never got to grips with the wing-down method, personally, but find crabbing reasonably straightforward.

As everyone else says, just get an instructor to demonstrate the various methods to you and take your pick.

[Chuck Ellsworth]

Hi DFC:

I am aware of the relasionship between where the ball is and balanced flight, what I am trying to point out is the simple fact that when entering a sideslip to correct for drift or to increase rate of descent it is necessary to lower the nose to allow for the increased drag of the sideslip.

Therefore it is obvious that if the sideslip is taught correctly the concern about stalling is not a factor.

I think what we have here is a lack of understanding on how to instruct rather than what method to use.

I must go now as I am late for an appointment.

Later:::p

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:D The hardest thing about flying is knowing when to say no.:D