The intricacies of cross-wind landing?

[Tailgate]

Miss Helen hit the Duxford Bump there as shown in that footage. Look closely and you can actually see the grass mound - nasty!

 

Hopefully that was an emergency landing and the unmarked ski jump isn't part of their grass strip. lol. I bet there was a bit of structural damage with that jolt. Obviously not a strip with those taxiways cutting across.

Edited October 4, 2012 by Tailgate

[VH-Rock]

Looks a little bouncy to me. Actually it looks a lot like some of my landings? ;)

 

9XuMylC7gSc

 

They had a mag failure and the engine lost power on final approach. There is a large grass hill, followed by a taxi way, followed by the grass strip. Miss Helen touched down before the grass as the pilot had no choice

[JimMack]

Miss Helen hit the Duxford Bump there as shown in that footage. Look closely and you can actually see the grass mound - nasty!

 

Actually - the Duxford bumb is an "in-joke" amongst pilots to explain a bad landing!

There is not one, the grass in that area he landed was a different colour!

[Yskonyn]

Wow that's a nice save actually!

It's it very easy to topple over the nose and there is no go-around with a failed magneto! :thumbup:

[Yo-Yo]

Bouncing? What bouncing? :)

 

Maybe a little bit...

[VIMANAMAN]

Nice Yo-Yo,

 

The first one is a thing of beautiful.

 

The second one uses the special technique I still practise regularly:)

Excuse no.1 'a deer ran across the runway. Honestly. Did no one see it?'

[VIMANAMAN]

Here's my range of outcomes with a decent xwind - it's very variable - more practise required...

 

 

This is the 'middle 3' of 8 circuits I did during one of many practise sessions - 8 is the most circuits I've managed with this weather setting without pranging before. I was knackered after 8 circuits, and for the first time in my self imposed practise program I left the runway with an unbroken Mustang.

 

I (now) really do think excessive bounce is controllable / avoidable but very very hard to get right? (in 1.2)

 

I can't remember if it says or not - weather was 11m/s 090 to rwy hdg, turb 2.5m/s - not beyond limits.

Edited October 5, 2012 by VIMANAMAN

[TX-EcoDragon]

Using only partial flaps is good idea, however you do not need to add much additional speed for a crosswind. Additional speed need only be added if the wind is gusty, and the general rule is to add 50% of the gust factor to your airspeed (ie. if the wind is 12kt gusting to 20kt, half the gust factor is 4, so approach 4kts faster than usual.)

 

As far as the technique: When further out on final approach you simply fly the extended runway centerline by doing a coordinated turn into the wind such that your ground track is appropriate, but your nose will not be pointing down the runway so as you near the landing flair you need to transition to the "sideslip" in order to point the nose down the runway while still preventing any lateral drift. Essentially you want to use the ailerons to bank into the crosswind such that you eliminate any lateral drift, and you simultaneously add opposite rudder to keep the airplane aligned with the runway. You will be in a slip and as such drag does increase some and so this is why some people will approach a little faster than normal. You maintain this cross controlled state until after touchdown and will touch down on the upwind wheel first, and then continue to add ever increasing cross controlled inputs as the airplane decelerates and aerodynamic control authority decays.

 

Here's a demo of a crosswind takeoff and landing that shows the technique fairly clearly:

 

 

I actually just discussed the issue of a crosswind landing with tail-wheel planes with a fellow pilot friend tonight, he said that to control the plane after tail-wheel touchdown you use the breaks, not the rudder to steer.

 

This is incorrect - you absolutely do not want to use the brakes for directional control in almost any scenario! Proper technique is to use the controls as outlined above - aileron into any crosswind, rudder opposite it, and if a swerve starts and you already have all the rudder applied then what you need to do is add a quick shot of power (not brakes). This serves to increase the authority of the rudder and elevator, as well as to increase directional stability. Any tailwheel pilot that uses lots of brakes on landing will not only add a lot of wear and tear to the airplane, but stands a pretty good chance of balling up the airplane when they are confronted with some wind.

 

My advice for tailwheel: I have never flown a tailwheel IRL yet, but will soon. I know what it's best to keep your tailwheel off the ground as much as possible, as the plane would rather taxi backwards, which leads to ground loops.

 

Sorry to nitpick you a second time, but this isn't really right either....I think you are thinking of the recommendation to use the "wheel landing" where the airplane lands at a more or less level pitch attitude. This can be useful in blustery conditions where there is some windshear, but generally the best best is still the 3 point landing where the tailwheel touches down either just before, or at the same time as the main gear. The truth is, you actually WANT the tailwheel firmly planted on the runway surface, so as soon as you touch the tailwheel to the runway, you should bring the stick back into your lap to help keep as much weight on the tailwheel as possible. Keeping the tail up eliminates that additional point of runway contact which quickly becomes critical as the airplane decelerates. Also, lowering the tail once the aircraft is slow also means that the relative impact of gyroscopic action of the prop is stronger, while aerodynamic control authority is minimal, which will lead to a yaw-wise swing when the tail comes down. There are still those pilots who will debate the notion of the 3 pt landing being the best landing in *most cases* but most of us with experience will say that in general, it is the way to go, even during strong crosswinds. Many piston engine warbirds also have prop clearance issues when in the level "wheel landing attitude" and so 3pt is mandatory for landings and tail low takeoffs are performed as well. Of course there are exceptions, such as airplanes like the DC3, or the Beech 18 which may lose some tail authority in the 3pt attitude, or when operating on rough/unimproved/rocky terrain the small tailwheel must be held clear of the terrain...etc.

 

In summary: during a crosswind do a 3 point, sideslip/winglow landing, pin the tailwheel down firmply as soon as you can get it there, keep the aileron into the wind after landing (and add more and more as you slow), and don't forget to position the controls correctly during taxi! :-D

Edited October 8, 2012 by TX-EcoDragon

[TX-EcoDragon]

Any time in Mustangs? Any substantive facts to back up your allegation?

 

I have some time in the 51, and find it to be a rather well behaved airplane as far as tailwheel airplanes are concerned. The wide track gear, long tail moment, struts, and the fairly low vertical component of CG make for a pretty honest airplane. I did encounter some more bounce character than I expected in the earlier beta, but I just tried out the current version of the sim and there wasn't much bounce to speak of and I feel that it does a pretty decent job of handling the touchdown.

Edited October 6, 2012 by TX-EcoDragon

[VIMANAMAN]

Nice one TX Ecodragon very informative, TY!

 

Very clear demonstration vid as well - excellent detail on the ailerons into wind procedure for T/O and Lndg rolls - learnt something there.

 

From this thread and with a bit of experience I'm now pretty clear on correct approach procedure - partial flaps, a touch of extra speed, offset the nose to maintain and track the extended centreline. Approaching the flare, apply balanced opposite rudder and aileron, to bring the nose and the centre line track together i.e. point it down the centre line, and this lowers the upwind wing. Flare touching down the upwind wheel first, and keep it there with increasing aileron pressure as you slow. With recent practise, execution of this is reasonably straightforward, but it's good to now know precisely what I trying to do, and that this is correct!

 

Touchdown and landing roll are where it can all go horribly wrong for me still -

Seems to be some debate on what's best with 3pt v wheel landings, but I guess that's because there's no absolute right or wrong?

 

I will try 3 pointers again, exactly as you describe, pinning the tail to the deck, with increasing windward aileron. A shot of power if I'm on the rudder stops and it's getting away from me. And thinking about it, it'll be an advantage simply going considerably slower! Lower forces and all that.

 

With a wheeler it is good to see the centre line at the flare, helps make sure you're lined up properly. But the transition from tailwheel fully off to being fully on, is as you say a directional nightmare. I'll keep trying these as well, pinning down the tail once it's touched down, and dito a shot of power when it gets away from me, and see if that helps also.

 

Re brakes - my intuition does indeed say leave them alone (until fully settled), but they are frequently saving the day at the mo! I'll try and stay off them. I'm probably over / under controlling the nose and creating my own problems, the rudder sweet spot is tiny and moving :). More finesse required!

 

Speaking of power control at touchdown can anyone confirm... 3 pointer = chop to idle at or just before touchdown? Wheel = ease it back slowly only AFTER touchdown? I guess this must be right? I think this is what I'm doing at the mo.

 

I'll try 3 pointers exactly as you suggest and also keep practising some wheels and see what works best for me out of all of the above. Any further pearls from anyone, most welcomed.

 

TY Dragon and all.

Edited October 6, 2012 by VIMANAMAN

[Tailgate]

TX-EcoDragon, I enjoyed your Xwind tutorial, very good instruction. It would be nice if you could create one specifically for DCS Mustang. It would be a good addition to the Mustang training wiki.

[JimMack]

Here is a hint, put clouds in the mission.

It gives you a visual point of reference as to direction, both on take off and a 3 point landing.

 

Nice one TX Ecodragon very informative, TY!

 

Very clear demonstration vid as well - excellent detail on the ailerons into wind procedure for T/O and Lndg rolls - learnt something there.

 

From this thread and with a bit of experience I'm now pretty clear on correct approach procedure - partial flaps, a touch of extra speed, offset the nose to maintain and track the extended centreline. Approaching the flare, apply balanced opposite rudder and aileron, to bring the nose and the centre line track together i.e. point it down the centre line, and this lowers the upwind wing. Flare touching down the upwind wheel first, and keep it there with increasing aileron pressure as you slow. With recent practise, execution of this is reasonably straightforward, but it's good to now know precisely what I trying to do, and that this is correct!

 

Touchdown and landing roll are where it can all go horribly wrong for me still -

Seems to be some debate on what's best with 3pt v wheel landings, but I guess that's because there's no absolute right or wrong?

 

I will try 3 pointers again, exactly as you describe, pinning the tail to the deck, with increasing windward aileron. A shot of power if I'm on the rudder stops and it's getting away from me. And thinking about it, it'll be an advantage simply going considerably slower! Lower forces and all that.

 

With a wheeler it is good to see the centre line at the flare, helps make sure you're lined up properly. But the transition from tailwheel fully off to being fully on, is as you say a directional nightmare. I'll keep trying these as well, pinning down the tail once it's touched down, and dito a shot of power when it gets away from me, and see if that helps also.

 

Re brakes - my intuition does indeed say leave them alone (until fully settled), but they are frequently saving the day at the mo! I'll try and stay off them. I'm probably over / under controlling the nose and creating my own problems, the rudder sweet spot is tiny and moving :). More finesse required!

 

Speaking of power control at touchdown can anyone confirm... 3 pointer = chop to idle at or just before touchdown? Wheel = ease it back slowly only AFTER touchdown? I guess this must be right? I think this is what I'm doing at the mo.

 

I'll try 3 pointers exactly as you suggest and also keep practising some wheels and see what works best for me out of all of the above. Any further pearls from anyone, most welcomed.

 

TY Dragon and all.

[sam777777]

What kind of crosswind are you guys talking about?

 

I fairly instinctively picked up the 10ms^-1 crosswind (20knt), which seems to be an operational extreme to me. I've read that the actual maximum is 25knts but I haven't tried that yet. Had an interesting incident with controls though, they kept locking themselves in the forward position, and then the hydraulic leaver came out automatically, as if I was somehow clicking those levers... so my first few landings had a failed downwind gear as well, after 4 landings I came down heavy and forced the gear up, breaking off the aileron. :music_whistling:

[JimMack]

What kind of crosswind are you guys talking about?

 

I fairly instinctively picked up the 10ms^-1 crosswind (20knt), which seems to be an operational extreme to me. I've read that the actual maximum is 25knts but I haven't tried that yet. Had an interesting incident with controls though, they kept locking themselves in the forward position, and then the hydraulic leaver came out automatically, as if I was somehow clicking those levers... so my first few landings had a failed downwind gear as well, after 4 landings I came down heavy and forced the gear up, breaking off the aileron. :music_whistling:

 

At Duxford, for Spits, P51Ds etc we have a max limit of a cross-wind of 20 mph.

[VIMANAMAN]

What kind of crosswind are you guys talking about?

 

I fairly instinctively picked up the 10ms^-1 crosswind (20knt), which seems to be an operational extreme to me. I've read that the actual maximum is 25knts but I haven't tried that yet. Had an interesting incident with controls though, they kept locking themselves in the forward position, and then the hydraulic leaver came out automatically, as if I was somehow clicking those levers... so my first few landings had a failed downwind gear as well, after 4 landings I came down heavy and forced the gear up, breaking off the aileron.

 

Hi Sam777777 - I started at 7, then 9 and have settled on 11m/s - which I make about 24.5mph - a bit fast but didn't know the limits when I started - I understand 13m/s is the limit for landing. (I was having some success so I stuck at it)

 

I've made heaps of progress (thx mainly to everyone that's contributed to this thread) and now I think I've got it reasonably reliably.

 

Here is a hint, put clouds in the mission.

It gives you a visual point of reference as to direction, both on take off and a 3 point landing.

 

Thanks JimMack - it was the second hint that finally made the difference :thumbup: (and everybody else's advice obviously) - big xwind = 3 pointers!

[VIMANAMAN]

Finally got it!

 

Still needs some work, especially T/O - bringing the stick from fully right and hard back to exactly where you need it, exactly when you need it, is taking some practise. And Lndg I'm still not fully straight some of the time, and still mis-judging my height at touch down. But I'm not braking Mustangs anymore:)

 

Big thanks to everyone that helped! (Very boring vid)

 

 

Was trying to workout where I got the idea wheel landings were the only way to go with xwinds...

 

It's page 133 of the manual -

 

Crosswind Landings

The recommended procedure for crosswind landing is as follows:

- Maintain airspeeds slightly higher than for a normal approach.

- Drop the wing into the wind slightly to counteract the drift, and keep the plane straight with the runway.

- Just before touching down, level the wings.

- Be sure to keep the stick back after touch down, so that the tail wheel will remain locked.

- Make a wheel landing if the crosswind is excessive, gusty, strong, or otherwise doubtful. Use approximately half flaps for any appreciable crosswind.

If crabbing is required during the approach, be sure to straighten out before landing. Never land in a crab as it is very stressful on the landing gear.

 

I'm not a real life pilot like a lot of you guys so this kind of mislead me - did I misunderstand this?

 

Anyway it's all good now, needs some polish but I've really learnt some stuff here! - thx again!

 

Right I'm off to blow some shit up! If I can remember how to fly in a straight line:)

 

EDIT: All of this is 1.2 vintage if the manual has changed then great! And ignore above.

Edited October 8, 2012 by VIMANAMAN

[ronht]

Here's where the computer simulation doesn't match reality with regard to wheel landings. If nothing else, start watching this video at the 7:40 mark through the wheel landing touchdown at the 8:30 mark. Notice that in the real aircraft, a fairly solid wheel landing touch-down, doesn't result in a bounce so high you lose sight of the airport, as happens in the simulation.

 

That is the difference I was eluding to in my previous comments about wheel landings not being realistic in regard to the over-all feel in the simulation.

 

[159th_Viper]

Maybe it's just me, but his rate of descent is very slight in that landing. He comes down fast and then arrests it a couple of metres above the runway and puts her down gently. In-SIM with that rate of descent she won't bounce either.

[Echo38]

I've had horrific bounces with a 100-FPS decent rate, which is about as low as you can reasonably expect in a P.C. sim with a flimsy plastic joystick and no tactile feedback. However, that was last patch; I'll try a few wheel landings in this version and see what happens. I'm actually having a harder time with my regular landings (3-point) in this version, simply because things've changed, and I need to readjust.

Edited October 8, 2012 by Echo38

[TX-EcoDragon]

Nice one TX Ecodragon very informative, TY!

 

Very clear demonstration vid as well - excellent detail on the ailerons into wind procedure for T/O and Lndg rolls - learnt something there.

 

You bet, I'm glad that it was helpful!

 

Touchdown and landing roll are where it can all go horribly wrong for me still -

Seems to be some debate on what's best with 3pt v wheel landings, but I guess that's because there's no absolute right or wrong?

 

I love doing wheel landings because they are fun and look cool, and that's a perfectly fine reason to do them! Other than off airport operations and certain aircraft which demonstrate aerodynamic shielding of the tail surfaces when in the 3pt attitude the main reason for wheelies is the cool factor. Yes, you can see over the nose, but you can raise the tail after a 3Pt landing too - if you needed to for some reason.

 

 

I will try 3 pointers again, exactly as you describe, pinning the tail to the deck, with increasing windward aileron. A shot of power if I'm on the rudder stops and it's getting away from me. And thinking about it, it'll be an advantage simply going considerably slower! Lower forces and all that.

Yep, lower speed = shorter ground roll, less damage if you DO ball it up, less wear on the tires and brakes...

 

With a wheeler it is good to see the centre line at the flare, helps make sure you're lined up properly. But the transition from tailwheel fully off to being fully on, is as you say a directional nightmare. I'll keep trying these as well, pinning down the tail once it's touched down, and dito a shot of power when it gets away from me, and see if that helps also.

 

In the real world, a tailwheel pilot becomes a master of using peripheral vision. You look straight ahead, even though there's nothing to see there, you look straight ahead but *see* everything in your peripheral vision. You don't want to turn your head or look off to one side very much at all - believe it or not you will be better off focused right over the nose and simply keeping the "slanted A shaped bits" of runway in your peripheral vision on the left and right side symmetrical. Another thing to do is burn the "sight picture" into your mind when you are sitting on the runway centerline in the 3pt attitude. Remember that image, and try to match it on every landing. If a moose happens to run out into the middle of the runway you are probably in trouble even if you could see it...so mostly we just try to keep the pointy end going straight, and the runway center line between our wheels!

 

Oh and as far as the throttle goes, in torquey planes like the Stang, you don't need to add a lot of throttle, and you can make things worse if you overdo it...just a quick, and brief shot of power should be enough!

 

 

Speaking of power control at touchdown can anyone confirm... 3 pointer = chop to idle at or just before touchdown? Wheel = ease it back slowly only AFTER touchdown? I guess this must be right? I think this is what I'm doing at the mo.

 

You can do either landing either way, and the way you mention is probably the most common (especially in a heavily laden aircraft). But I'm an opinionated sort and in the real world my stance is that if I need throttle during the landing flair and touchdown, then I've messed up. That doesn't mean it's always a bad idea, or that I will never use it....

 

Leaving some power on makes both of them easier, but touching down with power increases the touchdown speed, and trains bad habits. See the previous argument about the ideal landing happening at the lowest possible speed, plus if you always use power to land, you aren't going to like it when you land in such a way as to NEED the power and it's not there either due to a momentary hesitation, or an outright engine failure. I think it's better to practice the more difficult, but safer, power off approach and not be dependent on the mill turning to make a normal landing.

 

Once when checking out in a Fi-156 the check pilot wanted me to do wheel landings as he did, using only throttle to control the touchdown and little to no elevator, he had also advocated using power for 3pt landings because the airplane was a handful at high AoA when at idle power. I had done wheelies without using elevator inputs before, for fun and as a component of emergency maneuver training (it's a useful skill to practice failed/jammed elevator control) but not as a regular way to land. Initially I did it his way, and later when solo, and trying other things I could see that doing it the way I would normally was in fact a bit sketchy....I could wheel land it power off just fine, but doing 3pts with the nose high, the thing just comes down like an elevator and you can't really arrest the descent rate with MORE pitch, so you either plop it down firmly and let the Storch legs soak it up, or you add a shot of throttle and let it kiss the ground a little more subtly. So in this case, the SLOWEST forward speed is actually attained by a steep, nose high, power off approach and then a fist full of power just before crashing...err...landing (good times).

 

If you want to try the power on wheel landing in the Stang, just trim it for about 100-110mph, approach as normal, and then add a little power to arrest the descent rate around the time when you would normally add aft stick to flair (no I actually haven't done this in DCS - but I imagine it works). The reason leaving power on makes landing easier is because the additional power essentially makes the touchdown happen in slow motion because your descent rate is less, and the effects of induced drag as you increase the AoA are minimized, so you have more time to react and adjust to things.

 

 

So....the short answer is "Try them both ways, and if you can do them power off, then you're good!"

Edited October 8, 2012 by TX-EcoDragon

[TX-EcoDragon]

Maybe it's just me, but his rate of descent is very slight in that landing. He comes down fast and then arrests it a couple of metres above the runway and puts her down gently. In-SIM with that rate of descent she won't bounce either.

 

One thing is for sure, in the real world you feel things before you see them, and can correct sooner than you can in the sim - so I'm not really shocked that my real world landings are a bit smoother than my sim landings.

 

It does seem like the struts are a little less cushy in the DCS:P-51 though!

[Echo38]

+1, simply splendid explanation of everything, EcoDragon.

[ronht]

You bet, I'm glad that it was helpful!

 

If you want to try the power on wheel landing in the Stang, just trim it for about 100-110mph, approach as normal, and then add a little power to arrest the descent rate around the time when you would normally add aft stick to flair (no I actually haven't done this in DCS - but I imagine it works).

 

No it doesn't work, it should, but it doesn't, that's what I've been trying to point out. The slightest rate of descent on a two wheel landing will result in an over exaggerated bounce in full realism in the sim

[Yo-Yo]

I've had horrific bounces with a 100-FPS decent rate, which is about as low as you can reasonably expect in a P.C. sim with a flimsy plastic joystick and no tactile feedback. However, that was last patch; I'll try a few wheel landings in this version and see what happens. I'm actually having a harder time with my regular landings (3-point) in this version, simply because things've changed, and I need to readjust.

 

Actually, nothing has changed regarding FM and physics in the patch... :)

[Echo38]

Huh! I thought there was something improved about the tailwheel steering behavior on the ground?