Strong winds landing

[Kenan]

When doing a final correction ie. turning the nose towards the runway just before the touchdown (because of the strong winds it usually banks sideways during the whole approach), do you use trimmer/rudder pedals or simply roll the aircraft with the stick as if making the turn and then add some rudder to it?

 

I tried both and it's kinda easier for me to simply roll it and then afterwards use the rudder pedals to keep it straight once I already landed. If I use rudder pedals only, my aircraft tends to loose balance so I have to apply both stick (to the opposite direction) and the rudder at the same time.

[scheffchen]

When wind comes from the right direction there are 2 ways:

1) direct nose "into the wind" so you keep on drifting on the right pathway.

On final approach (30 meters before tuchdown) you should first use the rudder pedals to allign to the runway while compensation with the rolling the joystick a little to the right.

2) keep the right wing hanging down a bit so your roll-rate stabilizes your drift. This can be dangerous if crosswind is hard, because your wing might touch ground first, so you have to go horizontal seconds before touchdown

 

This scheme on wikipedia shows the methods nicely: http://en.wikipedia.org/wiki/Crosswind_landing

 

 

Most important rule is to never let the wind "under" your right wing, because this will cause instability at once. see here (ca. at 0:40 - 0:45):

 

 

Make a mission with a steady crosswind without any turbulences to practice the procedure. That helps a lot !:-)

 

Greetings

Boris

Edited April 19, 2011 by scheffchen

[Kenan]

That was very informative. Thanks! :)

[Scrobes]

Hopefully Headspace won't mind me linking this video he made, but I think it might help as it covers this topic. :) Watch in 720p!

 

[ErichVon]

When wind comes from the right direction there are 2 ways:

1) direct nose "into the wind" so you keep on drifting on the right pathway.

On final approach (30 meters before tuchdown) you should first use the rudder pedals to allign to the runway while compensation with the rolling the joystick a little to the right.

2) keep the right wing hanging down a bit so your roll-rate stabilizes your drift. This can be dangerous if crosswind is hard, because your wing might touch ground first, so you have to go horizontal seconds before touchdown

 

This scheme on wikipedia shows the methods nicely: http://en.wikipedia.org/wiki/Crosswind_landing

 

 

Most important rule is to never let the wind "under" your right wing, because this will cause instability at once. see here (ca. at 0:40 - 0:45):

 

 

Make a mission with a steady crosswind without any turbulences to practice the procedure. That helps a lot !:-)

 

Greetings

Boris

 

I am not a real life pilot, just a sim one.

 

Years ago, to Hershey Park's gardens (Pennsylvania) I was watching real pilots land on the airport runway not very far away. That day it was very windy. I watched them land for an hour while wife was having fun with the flowers.

 

Every propeller plane coming into land, came in really fast, into the wind, faster than a typical "nice day" landing.

 

Erich

:pilotfly:

[MasterZelgadis]

Maybe because of the crab and sideslip. You need more power to compensate for the crosswind. When you do the sideslip, that excess power generates forward thrust, making the plane come in faster..

[hassata]

Here's a fun post by BBall:

http://simhq.com/forum/ubbthreads.php/topics/3115890/Crosswind_Landings.html#Post3115890

[VF31_Subsonic]

The technique is simple in expression and tricky at first in practice.

 

You will be in a crab, nose into the wind, on final. If the crosswind is not too extreme your FPM will be on the touchdown point of the runway and your HUD ladder displaced to one side of the HUD.

 

At about 200-300 feet begin to transition from the crab to a forward slip. This is done by adding rudder input to align your nose with the runway (your HUD ladder should center), while simultaneously banking into the wind, which will be the opposite direction of your rudder input. Hold this all the way to touchdown, adjusting as needed for wind changes(little more or less rudder and bank adjusted...never really one without the other). As you bleed off speed your inputs should become slightly larger as control authority is lesser as speed decays. You will flare with some angle of bank and some rudder input and the upwind wheel should touch down first. Once planted you should be rolling full aileron into the wind to keep the upwind wing planted, although this is not essential in this sim, but proper technique and we are going for realism right? Retract flaps for max braking (less lift more weight on wheels) Roll out as normal with NWS applied at the proper speed.

 

As you refine your skill you can delay your transition from crab to slip until a lower alt or just over the fence even. I recommend the high and early transition to allow you to get a full feel for the wind and allow for alignment corrections down the glideslope so you don't wind up in the grass.

 

Erich, the speed you mentioned has nothing to do with crabs, slips, or thrust (well it still has to do with thrust). When you are flying on gusty days and often that is the case with cross winds but not always, you increase your approach speed by one half the gust spread to avoid stalls when the wind "dies". This is especially important when coming down the pipe in forward slip since you are effectively cross controlled and if you do experience a negative gust you could stall one wing deeper than the other since one wing is experiencing a greater relative wind, and well....thats how spins start and spins that low=BAD.

 

Hope that makes sense.

[bluepilot76]

jv44bubi

I think that was very well described! I think you might be a flying instructor in RL?

Cheers

[hassata]

Once planted you should be rolling full aileron into the wind to keep the upwind wing planted, although this is not essential in this sim.

 

Why do you say that? Just curious.

[VF31_Subsonic]

Lets say the wind is from the right front quarter....Full right stick raises that aileron, essentially spoiling lift and keeping that wing planted by lessening the chance that the relative wind of a strong gust will raise lift and the wing and create ground controllability issues(or in extreme cases flip a plane).

 

In the sim I dunno how well that is modeled as I have no messed with really strong winds so I am not sure it is essential....but IRL it is SOP (at least in GA aircraft) to aileron into the wind on the ground for a quartering headwind and aileron away for the quartering tailwind. Even if the winds are not extreme it is good practice for that day you land very lightly loaded in strong winds and you wish your habit was to always correct for the wind on the ground no matter how light it is. The airplane is always flying until it is tied down.

 

This link should help you visualize it....

http://www.glenndale.net/flight_training/training_aids/exhibits/Windcorrection.gif

[effte]

One of those topics where opinions vary. Adding half of the headwind and all of the gust factor (i e gust speed in excess of basic wind speed) works well to keep you out of trouble.

 

Normal procedure for the A-10 is also to add 10 knots to the recommended speeds for crosswind components in excess of 20 knots, in order to compensate for ASI errors as you slip into the wind on short final.

 

Example: 20G30, 20 knots gusting 30 from 45 degrees off the nose would mean a headwind of 14 knots, so add half of 14 plus all of the gust factor, 30-20, or 10 knots. An approach speed of 120 knots would then become 120 + 14/2 + 10 = 137 knots.

 

For extreme weather, this has to be applied with a bit of common sense. Try applying the rule of thumb blindly in 30G49 down the runway... and prepare to go supersonic on the approach. :)

 

Aileron into the wind is not required for the A-10. The wide track means the wind is not likely to lift the upwind wing.

 

You add half of the headwind as you can expect the wind to drop as you descend. If your approach speed is 120, your stall speed should be in the region of 90 knots. Imagine coming down the approach, fat dumb and happy, at exactly 120 knots. Then you enter the still air behind an obstacle, and that headwind goes away. All of a sudden, your airspeed drops by 14 knots - half your stall margin. Then a gust comes along from your rear, dropping your airspeed a further ten knots. Now you're at 96 knots... and then you correct the wing drop caused by the gust using aileron, increasing the effective angle of attack of one wing tip and thus increasing the stall speed of that wing. That's the recipy for an incipient spin down low, a surefire way to get yourself killed.

 

There are really three different crosswind techniques:

 

1) Fly the aircraft in a crab (nose pointed into the wind) all the way to touchdown. Hard on the landing gear, but landing gears are designed to take a lot of punishment. Apparently the mains of the B747 are built to take the beast coming down at a 45 degree crab. Slightly overdesigned, if it's not a hangar tale, but they should cope with a lot. The A-10 dash 1 clears landing in a crab as long as you see the runway through the center windscreen a 10 degree crab.

 

2) Fly the aircraft in a crab until just before touchdown, when you push the downwind rudder pedal to align it with the runway. Apply aileron as required to keep the wings level. Must be initiated late enough for the inertia of the aircraft to prevent the aircraft from starting to drift downwind to any significant degree, or that downwind row of runway lights will start coming close very quickly indeed.

 

3) Fly the aircraft in a crab until short final, where you align the aircraft with the runway and lower the upwind wing into the wind to enter a slip to prevent the aircraft from drifting off the runway centerline. The distance at which you go from crab to slip can be varied due to conditions and personal preferences. You touch down still in the slip, upwind wheel touching first.

 

(1) is easy, but hard on the equipment. Still, making mess out of (2) or (3) will likely be more damaging.

 

(2) requires careful timing, but as you touch down level it is good if you have low-slung podded engines far outboard, or if you have stores under the wing which reduce ground clearance.

 

(3) is easy, but you risk striking a wing tip, an engine pod or stores on the runway if the bank angle is too large. You are applying crossed controls, so be vary of your air speed. Remember that you cannot trust your ASI when you are in a slip. Landing on one wheel first effectively increases the damping in the landing gear, making it easier to land smoothly and avoid bouncing.

 

All three can then be combined to varying degrees.

[hassata]

I think the ground handling as it relates to wind is modeled effectively. Give it a try. On take-off I sometimes have to adjust as you describe, especially in the Su-25.

[VF31_Subsonic]

One of those topics where opinions vary. Adding half of the headwind and all of the gust factor (i e gust speed in excess of basic wind speed) works well to keep you out of trouble.

 

Agreed there are essentially 3 techniques...I essentially illustrated two and then three since most folks in combat sims have never really had to deal with cross winds or wind factors modeled this well before and I agree with your points on three, although I doubt we will never fly missions in this sim with winds severe enough to strike weapons on the pavement. Most guys will be lucky to be remotely near center line in that case.

 

I should have added in there this is all in relation to what your headwind component is, but the adding of all the headwing and half the gust to your approach speed is new technique to me. I can see where it gives you a larger margin of error but yes, approach speeds could get out of control in higher winds.

 

Normal procedure for the A-10 is also to add 10 knots to the recommended speeds for crosswind components in excess of 20 knots, in order to compensate for ASI errors as you slip into the wind on short final.

 

Good to know

 

Aileron into the wind is not required for the A-10. The wide track means the wind is not likely to lift the upwind wing.

 

Didn't think so due to weight/track/modeling, put that in there for illustration purposes for those wanting to fly the little ones at some point in life. May as well develop good habits in the sim.

 

You add half of the headwind as you can expect the wind to drop as you descend.

 

Not sure I am onboard with this since although often winds can be the same or even more lower for many reasons.

 

There are really three different crosswind techniques:

 

1) Fly the aircraft in a crab (nose pointed into the wind) all the way to touchdown. Hard on the landing gear, but landing gears are designed to take a lot of punishment. Apparently the mains of the B747 are built to take the beast coming down at a 45 degree crab. Slightly overdesigned, if it's not a hangar tale, but they should cope with a lot. The A-10 dash 1 clears landing in a crab as long as you see the runway through the center windscreen a 10 degree crab.

 

2) Fly the aircraft in a crab until just before touchdown, when you push the downwind rudder pedal to align it with the runway. Apply aileron as required to keep the wings level. Must be initiated late enough for the inertia of the aircraft to prevent the aircraft from starting to drift downwind to any significant degree, or that downwind row of runway lights will start coming close very quickly indeed.

 

3) Fly the aircraft in a crab until short final, where you align the aircraft with the runway and lower the upwind wing into the wind to enter a slip to prevent the aircraft from drifting off the runway centerline. The distance at which you go from crab to slip can be varied due to conditions and personal preferences. You touch down still in the slip, upwind wheel touching first.

 

(1) is easy, but hard on the equipment. Still, making mess out of (2) or (3) will likely be more damaging.

 

(2) requires careful timing, but as you touch down level it is good if you have low-slung podded engines far outboard, or if you have stores under the wing which reduce ground clearance.

 

(3) is easy, but you risk striking a wing tip, an engine pod or stores on the runway if the bank angle is too large. You are applying crossed controls, so be vary of your air speed. Remember that you cannot trust your ASI when you are in a slip. Landing on one wheel first effectively increases the damping in the landing gear, making it easier to land smoothly and avoid bouncing.

 

All three can then be combined to varying degrees.

Great detail on all three. As far as trusting the ASI, only the POH can tell you what to expect in deviation when in a slip...not sure how far off it is in the A10 though it does not feel like much. Bottom line is it is variable, challenging since the inputs are changing for gusts and obstacles, but fun as hell and satisfying when you get it down right!

[doright]

Don't confuse ground taxiing in high winds with winds in flight.

 

Most important rule is to never let the wind "under" your right wing, because this will cause instability at once. see here (ca. at 0:40 - 0:45):

...

 

The video doesn't show wind getting "under" the wing. The airplane is still in the air and therefore moving with the airmass. What the video shows is the effect of a rapid yaw causing differential lift or possibly partial stall of the left side.

[ErichVon]

When doing a final correction ie. turning the nose towards the runway just before the touchdown (because of the strong winds it usually banks sideways during the whole approach), do you use trimmer/rudder pedals or simply roll the aircraft with the stick as if making the turn and then add some rudder to it?

 

I tried both and it's kinda easier for me to simply roll it and then afterwards use the rudder pedals to keep it straight once I already landed. If I use rudder pedals only, my aircraft tends to loose balance so I have to apply both stick (to the opposite direction) and the rudder at the same time.

 

This is my favorite video:

=================

 

 

and check out the other related videos, after.

 

Watch the 1st link until he actually lands.

 

Ever see a B-52 do a crosswind landing? Pretty cool.

 

When the CIA hired pilots to fly non-military during 'Nam was pretty cool stuff.

 

The Navy Reserve hired Evergreen Airways out of Iceland to fly our battalion to the Gulfport, MS airport, late 1970's, for our annual ACDUTRA. I think the pilot got his license out of a Cracker Jack box. He really scared us landing and again taking off. 1st time down was cloud to about 500 feet and he was half off the runway, over grass. He had to go around again.

 

Leaving: I helped load the baggage on that jet; it was stuffed to the gills underneath. He used every last inch of runway, leaving. I swear our wheels touched the top of the fence.

 

 

Erich

:pilotfly:

Edited April 21, 2011 by ErichVon

[Flamin_Squirrel]

Flaps reduce stability in both pitch and roll so in windy, especially gusty conditions, it might be worth landing with partial flaps. This will require higher approach speeds.