Which Cross Wind Technique

[dutchroll]

How to do it, or how not to?

Yeah to be honest I admire people who have the foresight and skill to recognise that they really need to go-around and give it another shot. Wish I could say the same for that guy!

 

 

[David Isaac]

How the hell he maintained control in that little bit of low level tap dancing is amazing in a tail dragger. Apart from the fact he should have gone around (you could see the gusting wind in the tree movement), that was an amazing bit of control.

 

Notice his "controlled ground loop" at the end. Able to be done because his ground speed was so low and swinging it into wind meant he wasn't going to go over. Sounded and looked like a C180, I love those old birds ...heaps of rudder and aileron authority, pretty evident in that example.

 

The amazing part is he got it down ... was it skill, definitely a lot of that or he would have lost it. Was it good luck, maybe a bit of that too given what we witnessed. He was lucky the runway was that wide.

 

 

[metalman]

Not sure if it's a Cessna, looks like a glass air sportsman, pretty freaky weather to be flying in,

 

 

[David Isaac]

Yeah, Matty you could be right, the tail is a little too swept back for a 180, sure sounded like a 6 cylinder and the way the wheel hung out the back made me think it was a C180.

 

 

[facthunter]

A global is a version of a Volkswagen two cylinder engine, conversion. I posted this days ago but my keyboard died. and it sat there. Nev

 

 

[metalman]

Yeah, Matty you could be right, the tail is a little too swept back for a 180, sure sounded like a 6 cylinder and the way the wheel hung out the back made me think it was a C180.

it's probably the wildest crosswind landing I've seen,either great skill,,,,huge amounts of "brown adrenaline" ,or dumb luck,,,,going by the apparent touchdown ground speed I might have (and given room do now) tried landing into the wind regardless of where the runway is,,,still, I wasn't the one doing battle that day!

Heres one I got sent a while back, he has a few goes then gets smarter,,,or tired of being scared!

 

 

 

[Guest Maj Millard]

First big mistake there of course is he is trying to plant it on pavement instead of the grass, those planes were never designed for pavement. Ten times harder then sticking it on the grass !........he actually had it on in the first try, all he had to do was to get off the power and suck the stick back, so it says stuck......Maj....

 

 

[facthunter]

A few things there didn't add up. The wind was not strong enough to prevent him making headway into it, easily on approach. The wings were able to be kept level and not rocking as they tend to do on tripers and why would you do a three pointer in a wind like that? ( and keep the power ON). Nev

 

 

[dutchroll]

How he avoided smashing up his plane and himself in the first 4 minutes I'll never know. Not the wisest piece of aviation I've seen.

 

 

[metalman]

First big mistake there of course is he is trying to plant it on pavement instead of the grass, those planes were never designed for pavement. Ten times harder then sticking it on the grass !........he actually had it on in the first try, all he had to do was to get off the power and suck the stick back, so it says stuck......Maj....

yeh, in that position, and I've been there plenty, I go to his final decision real quick, as for the conditions, I've been filming a bit lately and it amazes me how the camera doesn't convey they true conditions, I've been on final getting chucked all over and then watch the video and thought "where did all the wind go",

 

 

[M61A1]

A few things there didn't add up. The wind was not strong enough to prevent him making headway into it, easily on approach. The wings were able to be kept level and not rocking as they tend to do on tripers and why would you do a three pointer in a wind like that? ( and keep the power ON). Nev

It looks a little like something (terrain or buildings) may have masking the wind, or something funneling it at a point further down. The wind seemed worse right after where he was trying to touch down. I experienced something like it ( not as severe)when landing at a friends place out on the plains, all the dwelling areas there have trees planted as windbreaks. The last bit of my approach was shielded by the wind break, didn't really think about it, thinking all is sweet, holding off, ready to touch down as I passed the wind break, that's when it all went to poo, quite untidy. No damage, luckily , learned a lesson.

 

 

[Phil Perry]

CROSSWIND LANDINGS ?

 

This is an interesting subject isn’t it ?? This question has been coming up for years and it will continue so to do as long as we have NEW pilots learning to fly and ( hopefully ) land aircraft safely. the POH for ANY aeroplane type will quote a MAX crosswind limit of X knots, . . . and it is fair to assume that this figure is going to be the sum T O T A L sidewind component, otherwise and popularly known as “crosswind”, . . .ie, not dependent upon from which angle to the particular landing runway that the wind is orientated.

 

LINEAR OR LOGARITHMIC ??

 

The next question for the landing pilot is this; is the crosswind quoted going to affect his aircraft in a

 

linear or logarithmic fashion. . . . .( ? ) OK, let’s look at it like this. . . . . acceleration of ANY kind, is measured logarithmically. . . . . so if a sidewind is quoted as two knots, it follows that a sidewind of this figure will have an effect approximating four times two knots, as it is dependent upon the laws of logarithmic physics, ( tangential velocities ) and as such, it is not a smooth, linear transition between wind velocities. Then you have to factor in the angular difference from runway centreline, and you have quite an interesting mathematical situation. { This stuff is really for Geeks and let’s not go too far into that } For instance, landing on runway 27, a twenty five knot wind at 215 degrees will produce a crosswind factor of “X” knots. NOW,. . . . what if the wind direction is 205 degrees at twenty five knots ? ? ? Rwy 27 is still the best runway, BUT what would be the logarithmic total crosswind with which your aircraft would have to handle ? and would it be capable ? even if YOU were ( ! ) And what if it was a Gusty crosswind . . . .? ? ? ? it'd be whizzing up and down the logarithmic scale a little, with a constantly large variation of effect upon lighter machines.

 

Regrettably, the aircraft designers don’t know which way the wind will be coming from on landings when they set the max crosswind limits for a particular machine. . . . so this appears to be where all the questions arise, and the poor old air traffic controller can ONLY give you the wind DIRECTION AND VELOCITY . . . . It’s the pilot who has to decide if this surface wind is acceptable for his machine type in order to effect a safe landing.

 

I have read various posts with some interest, regarding what various owners believe that the max crosswind limit is for their particular aeroplane and some of them are quite amusing, (although I must qualify that by saying that they are only repeating what their POH or aircraft designer says. . ).

 

I heard today from my friend Simon, (A local pilot ) that his Savannah machine has a max crosswind limit of thirty knots. ( ? ) blimey, I know of certain rather heavy metal types which have a limit of nearly half of that and I certainly wouldn’t want to try and land a light aircraft of ANY kind in a sidewind approaching that velocity, because, in MY experience . . . . it would fall outside both the controllability of the aircraft and probably MY ability to fly it. . . ! and I would more than likely break it and have to limp to the airport bar for my treble vodka and serious apologies to the FBO.

 

From memory, (which isn’t that good at my age ) the crosswind max limit on a C-172 is around 17 knots. . . . ( I have around 370 hours on type plus some on 182. . . but this was a long time ago .)this is a much bigger and heavier beast than a Savannah, with much bigger ailerons and a lot more inertia, so. . . . . I don’t know where the SLA salespeople get these impressive crosswind figures from. . . . . unless Cessna reduced their book numbers to preclude any possible litigation. . . . .

 

I must admit though, I really DO like all the varied ideas and opinions regarding crosswind landings, and this is why I love forums so much. . . .I used to be addicted to cocaine, but the flying forums are much cheaper, and don’t get up my nose anywhere near as much.

 

Happy Groundloops . . . ( ! )

 

Phil

 

 

[poteroo]

First big mistake there of course is he is trying to plant it on pavement instead of the grass, those planes were never designed for pavement. Ten times harder then sticking it on the grass !........he actually had it on in the first try, all he had to do was to get off the power and suck the stick back, so it says stuck......Maj....

Yup - a Glasair Sportsman. As MM says, one of the little tricks that can be used in these situations is to land on the grass - on the upwind side of the sealed or gravel runway. That alone helps keep your wing down into wind. Unfortunately, this Sportsman never was placed into a proper wing down attitude -so it's no wonder he was shifted laterally onto the downwind side of the runway where it's more likely the wind will lift his into wind wing. (it did-and he was lucky to recover it). Many pilots show an aversion to lowering the wing on the left side. Yes, you'll have to use a lot of right rudder if your ailerons are effective - but that is the answer. Judicious use of power makes rudder more effective, and control is very important here.

 

 

 

One observation made after many years of eyeballing windsocks, is that pilots don't look at them carefully from above to determine direction, and they don't understand how to determine wind speed by the 'hang' of the sock. So many mistakes made with wind determination - no wonder there are so many crosswind/downwind related incidents. Also, with experience, pilots learn that the stronger the wind - usually the greater the swings in direction, and in the vertical gusts that result from mechanical interference. When in doubt - flypast the sock and get an appreciation of what to expect - it's smarter than trying to work it all out on short final!

 

 

 

In any case - whatever happened to landing more diagonally into wind? If you already have a relatively low approach speed - by taking 20-30 degrees into wind, off your runway heading, you further shorten the landing roll, plus reduce the cross-wind component. In desperate situations such as where the cross-wind component is judged to be way above the POH maximum - all bets are off, and it's a case of save yourself ! Think about the numbers:

 

 

 

runway is 32, wind 270/25 = xwc of 18kts, or beyond your bugsmashers POH limit of 14kts. Change your direction from 32 to 30, and the xwc is closer to 12kts, ie just within limits. But, your landing roll is shortened considerably. On 32 the h/w is 15kts, but in the 30 direction it is 21kts. You won't need as much distance - so you can do it.

 

 

 

Yes, I expect to hear all the reasons why you can't, shouldn't or wouldn't do this. However, pilots need to develop life-saving skills which might well be beyond what's written down in textbooks. It's unwise to adopt such pious, precious attitudes when you've never tried it. Get a competent instructor and try it. You will be surprised at the difference a few degrees makes.

 

 

 

happy days,

 

 

[Phil Perry]

Yes !! We laugh at it each time we use full flap !

Hi Ian,. . . . .

 

I used to fly an Auster regularly out of Casey airfield near Berwick Vic, back in the early 70s,. at Groupair flying Club, Keith Hatfield's place. . . .I think that the reg was VH-ARX . . . I saw what I believe was the same machine on the front cover of an Auster Club magazine some years ago. It had lost it's all over white colour and had been painted in airline livery, silver, red and white, but I can't remember what airline ( Ansett ? ? ? ) and it was privately owned by then by a bloke down in Gippsland but I can't remember the name of the airfield. I seem to remember that it had split flaps, very similar to those you mentioned and an operating ;lever above left in the cabin. It was a four seat version, as I regularly took rear seat passengers up in it and I'm sure it wasn't a "Six" as I helped restore one of those quite recently, which had been an artillery spotter variant with a huge rear window panel and one rear facing seat and it had separated frise flaps which hung below the wing trailing edge unlike the split type on the earlier models.

 

Lovely aeroplane though, dead easy to fly ( for us old blokes anyhow ! ! )

 

Phil

 

 

[Camel]

Poteroo thankyou for your wise professional comments and agree totally with you.

 

The videos posted do not illustrate skillful techniques in my opinion and am surprised they did not end in disaster.

 

I have landed on sevseral occasions in severe crosswind and know what's involved.

 

I used to live in a windy place and learnt to deal with it so when I was in severe crosswind I knew what to do but the experience of landing a C172 in around 50 knot quartering side wind at Broken Hill was testing, the flying doctor took off before me and the mailman landed after me in a Cherokee six which I watched and he did make it look easy. On the way to Broken Hill the land was covered by a severe dust storm, this was Sept 2002. The next severe one was landing at Port Augusta in a J230 with a full 20kt plus direct cross wind, which on the first attempt was not looking good so I went around straight away my second attempt was perfect and totally controlled .

 

From my experience I have learnt do not rush the landing, take your time, set it up , stay calm ,you can only land in these conditions with a defensive calm attitude. As Poteroo said if you watch the wind socks you will know what is happening and what the best options are.

 

When I was a student pilot I witness some of my instructors land in severe conditions and remember them smiling and laughing at my fear.

 

 

[rgmwa]

CROSSWIND LANDINGS ?LINEAR OR LOGARITHMIC ??

 

The next question for the landing pilot is this; is the crosswind quoted going to affect his aircraft in a

 

linear or logarithmic fashion. . . . .( ? ) OK, let’s look at it like this. . . . . acceleration of ANY kind, is measured logarithmically. . . . . so if a sidewind is quoted as two knots, it follows that a sidewind of this figure will have an effect approximating four times two knots, as it is dependent upon the laws of logarithmic physics, ( tangential velocities ) and as such, it is not a smooth, linear transition between wind velocities. Then you have to factor in the angular difference from runway centreline, and you have quite an interesting mathematical situation. { This stuff is really for Geeks and let’s not go too far into that } For instance, landing on runway 27, a twenty five knot wind at 215 degrees will produce a crosswind factor of “X” knots. NOW,. . . . what if the wind direction is 205 degrees at twenty five knots ? ? ? Rwy 27 is still the best runway, BUT what would be the logarithmic total crosswind with which your aircraft would have to handle ? and would it be capable ? even if YOU were ( ! ) And what if it was a Gusty crosswind . . . .? ? ? ? it'd be whizzing up and down the logarithmic scale a little, with a constantly large variation of effect upon lighter machines.

 

Phil

Acceleration and logarithmic total crosswind, Phil?. In my simple world the airmass is moving and the aircraft is just being carried along with it until it lands. Once on the ground the wind applies a force to the aircraft and assuming it was initially stationary it would want to accelerate along the ground in the opposite direction to the wind, if it was free to do so, until it was moving at the same speed as the wind. At the point the wind stops pushing and the plane just keeps skating along at the same speed (in an ideal world). Crosswind component for 25kts and 270/215 is 20.5kts. At 270/205 is about 22.6kts. The variation is not linear with changing angle (same for the headwind component). Are you winding us up, or am I just thick and not getting what you're saying?

 

 

[Guernsey]

Cute little Kitten ... Love the sound of that two potter. Is the brand 'Global'? Never heard of it.

I had one in my first Supa Pup Mk2.

 

Alan.

 

 

 

[fly_tornado]

spare a thought for those flying around Europe at the moment.

 

https://www.youtube.com/watch?v=sqVU2YDTCkY

 

 

 

[M61A1]

Acceleration and logarithmic total crosswind, Phil?. In my simple world the airmass is moving and the aircraft is just being carried along with it until it lands. Once on the ground the wind applies a force to the aircraft and assuming it was initially stationary it would want to accelerate along the ground in the opposite direction to the wind, if it was free to do so, until it was moving at the same speed as the wind. At the point the wind stops pushing and the plane just keeps skating along at the same speed (in an ideal world). Crosswind component for 25kts and 270/215 is 20.5kts. At 270/205 is about 22.6kts. The variation is not linear with changing angle (same for the headwind component). Are you winding us up, or am I just thick and not getting what you're saying?

I think what Phil is saying is, basically using the "drag increases at the square of the velocity" thing to say that if the cross wind speed doubles, then the force it applies to your aircraft multiplies by four, and that because of this one should exercise caution in assessing what is acceptable. Yes the aircraft is in the body of air, but especially when you are trying to land, you must also try to maintain an accurate position in relation to the ground as well, and the control authority required, will not necessarily increase in a linear fashion.

I think I've said that right, I sure someone will tell me if I didn't.

 

 

[rgmwa]

I think what Phil is saying is, basically using the "drag increases at the square of the velocity" thing to say that if the cross wind speed doubles, then the force it applies to your aircraft multiplies by four, and that because of this one should exercise caution in assessing what is acceptable. Yes the aircraft is in the body of air, but especially when you are trying to land, you must also try to maintain an accurate position in relation to the ground as well, and the control authority required, will not necessarily increase in a linear fashion.I think I've said that right, I sure someone will tell me if I didn't.

OK, if that's what he's getting at then it makes more sense. I suppose another way of looking at it is if you're trying to hold runway alignment in a cross wind and the wind speed doubles then drag goes up by four and you will need four times more compensation, either via more crab angle, power or horizontal lift component or a combination of these to stay on track.

 

rgmwa

 

 

[Phil Perry]

Acceleration and logarithmic total crosswind, Phil?. In my simple world the airmass is moving and the aircraft is just being Are you winding us up, or am I just thick and not getting what you're saying?

I agree entirely RGM, and no, I wasn't intending a wind - up. That piece is taken nearly verbatim from an aero club lecture I attended about six years ago at RAF Cosford with the subject matter being "Landing of light, versus heavier airframes" where the lecturer went into all manner of crosswind dynamics, which didn't make a whole lot of sense to me either ! ! I remember that there was a fairly heated ( but polite ) series of arguments from the flight instructors and other experienced pilots in the audience, and there then ensued some deep technical questions involving exponential fluid dynamics and Reynolds equations . . . . after which I think that most of the newer pilots were more perplexed than when they started !

 

And yes M61,

 

That condenses nicely what the lecturer was probably getting at, even though his exponentiation equations were possibly more intended for post-grad aerodynamicists than a bunch of lowly civvy pilots and students. Phil

 

 

[Aldo]

The best method is the one that you are most comfortable with to be able to complete a satisfactory landing.

 

Couple of things to remember though

 

• If the forecast wind at you destination is greater than the published max x-wind for your aircraft then you must plan an alternate where the wind strength is less or there is a runway more into wind to reduce the x-wind component.
   
   
  
• The landing is not complete until the aircraft is parked and tied down - many pilots have come to grief following touchdown and go phew glad that's over, only to find that the problems have only just started.
   
   
  
• The more precise your circuit and approach the better the result - if your not happy the earlier you decide to shoot a missed approach the better, go round and get it better set up next time, providing you have enough fuel you can do this as long as you like, there should be no pressure on private (or commercial for that matter) pilots to get it down on this approach - forget about what other people think and concentrate on what you are doing.
   
   
  
• Don't overthink the situation, there is only one (1) thing that you have to do with a x-wind landing in a light aircraft and that is to control the drift - i.e. the wheels should be pointing straight down the runway at touchdown, all the rest is the same
   
   
  
• If all else fails and you don't have the fuel required to go somewhere else or keep trying, find a road that is into wind do a couple of good precautionary runs to check for obstacles (power lines, vehicles, trees and the like) and put it down there - you will no doubt get your butt kicked by CASA and others but I would rather be alive and asking for forgivness than be dead and have my actions or lack of discussed on a forum such as this one.
   
   
  
• Above all else practice, practice and more practice competency is all about currency.
   
   
  

 

 

Personally I find it easier to lay off the drift (nose into wind) and fly a normal approach, as I approach the flare bring the nose to be aligned with the centre line with rudder and control the drift with aileron, once on the ground maintain full into wind aileron, get the flaps away (only if you have control) and start breaking to get the speed washed off.

 

Aldo

 

 

[David Isaac]

Or if you are in an Auster, approach at 40knots with full flap and land across the strip, choose a spot with a taxi way adjacent to the strip ... Oh and you had better broadcast your intentions. With a decent cross wind you would probably stop in less than 7o metres.

 

 

[kaz3g]

I have been trying to find a YouTube video that DJP sent to the list some time ago. It shows an Auster handling a hell of a x-wind at Moorooduc back in the good old days. Couldn't find it but this one is a bit of a hoot:

 

 

If it won't work (I am a technological dinosaur) then google "Auster on the loose"

 

Kaz

 

 

[poteroo]

Or if you are in an Auster, approach at 40knots with full flap and land across the strip, choose a spot with a taxi way adjacent to the strip ... Oh and you had better broadcast your intentions. With a decent cross wind you would probably stop in less than 7o metres.

Actually - 59m in a SuperCub with 35-40 kts. Vso of 33....so could almost step out! Gustiness is what prevents you from actually doing it in zero distance. happy days,