Take off in Cross wind

[zoomie36]

Well, much much anger trying to take off in crosswind. For starters, there is no wind direction in which the cross wind is, i am assuming if the weather states 17 degrees, it means winds are from 017? Or does it mean 170. In either case when I attempt to take off i usually get to about 50-70 knots and the aircraft yaws to the right and then i thunder in. :mad:

 

Anyone have some tips? Wish there was a better weather read out so at least I could know for sure which way the cross wind is hitting me.

 

Thanks in advance

 

signed

 

frustrated flyer

[effte]

17 degrees is 17 degrees.

 

In the real world, it is always FROM. In the DCS mission planner, it is still TO. From the in-game ATC, I think it has been both but I would hope it is FROM by now. Should be apparent after the first approach which it is. :)

 

I don't bother flying the propeller aircraft in crosswinds for now, and I would recommend you to do the same and save yourself the frustration.

 

/Fred, taildragger rated

[Art-J]

I presume we're talking about "crosswind takeoff" mission of P-51 campaign, on Beslan Airport? Then, the direction in briefing is "to" 17 degrees i.e. when standing on treshold of runway 28 You get the wind blowing from the left. I admit I didn't check what direction ATC is giving though.

[[DBS]TH0R]

I don't bother flying the propeller aircraft in crosswinds for now, and I would recommend you to do the same and save yourself the frustration.

 

Seconded.

[VH-Rock]

Crosswind take-offs aren't too bad when you get a little experience with the Mustang. Power up gently, no higher than 45" MP, 3000 RPM.

 

Use the rudder to keep the aircraft on the centre line and hold the stick to the direction that the wind is coming from. Practice makes perfect.

[[DBS]TH0R]

Can't speak for effte, but for me it isn't the difficulty but the current physics modelling that is putting me off.

[Anatoli-Kagari9]

It certainly is a complex question...

 

I posted sometime ago on this subject, that I was finding the "deflected propwash" effects overdone, but after exchanging a few PMs with a fellow who owns a Hornet Moth and replied to one of my topics at PPrune, I confess I am confused :-/

 

This piot, with thousands of hours logged on all sorts of aircraft, including many taildraggers, sort of confirmed that this might indeed hapen at extreme x-wind situations, the kind of no one would dare taking off in...

 

Common sense still makes me think it needs to be fine tuned though...

 

I've found that, under strong x-wind, taking off without flaps, and smoothly applying throttle instead of firewalling it at the start of the takeoff run makes it "piece-of-cake" :-) Flaps and the effects they have greatly enlarge asymmetric the deflected propwash over the downwind wing.

Edited November 4, 2014 by jcomm

[[DBS]TH0R]

This piot, with thousands of hours logged on all sorts of aircraft, including many taildraggers, sort of confirmed that this might indeed hapen at extreme x-wind situations, the kind of no one would dare taking off in...

 

Interesting. What does he define as extreme x-wind?

[HotTom]

Many (most) folks may already know this but it is worth repeating, I think:

 

The affect of a cross wind (either landing or taking off) is on the tail of the plane, NOT the nose.

 

Thus, if the wind is blowing from right to left it is going to push the tail to the left and thus the nose will be pushed to the right, INTO the wind.

 

Seems simple but it is counterintuitive and it took a long time of getting the Cessna (back when dinosaurs still roamed the Earth) I learned in straightened out "instinctively." If the wind is coming from the right, the nose will want to drift right (into the wind) so you need to use the rudder to keep the nose to the left.

 

Again, apologies to those who already know this.

 

Also, the portion of the manual on cross wind takeoff and landing gives some very useful tips.

 

This is another one of those things that requires doing it over and over again to get the right "feel." The "Create Fast Mission" function is good because wind increases with the cloud setting. It took me awhile to feel confident in takeoffs and landings with a cross wind but I can do it, anyone can!

Edited November 4, 2014 by HotTom

[Tucano_uy]

The key is: KEEP THE TAIL WHEEL ON THE GROUND and the STICK FULL BACKWARDS up until about 100mph.. If you try to raise the tail before, when you have not enough rudder and aileron authority, it's going to hurt.

 

 

50m/s take off

 

http://forums.eagle.ru/showpost.php?p=2221266&postcount=5

Edited November 5, 2014 by Tucano_uy

[[DBS]TH0R]

Thus, if the wind is blowing from right to left it is going to push the tail to the left and thus the nose will be pushed to the right, INTO the wind.

 

The deflected slipstream will apparently move the nose in other direction. ;-)

[effte]

Thus, if the wind is blowing from right to left it is going to push the tail to the left and thus the nose will be pushed to the right, INTO the wind.

 

And that's the point - in DCS, it doesn't.

 

There only one conclusion to be drawn: DCS has unearthed a flaw in reality.

 

The real world will be updated to implement this in the next patch.

 

:pilotfly:

 

Kidding aside, I'm sure we'll see convergence eventually.

 

Cheers,

/Fred

 

Edit: Wasn't there a post identifying or even linking those reports? I can't seem to find it.

Edited November 5, 2014 by effte

[HotTom]

And that's the point - in DCS, it doesn't.

 

There only one conclusion to be drawn: DCS has unearthed a flaw in reality.

 

The real world will be updated to implement this in the next patch.

 

:pilotfly:

 

Kidding aside, I'm sure we'll see convergence eventually.

 

Cheers,

/Fred

 

Edit: Wasn't there a post identifying or even linking those reports? I can't seem to find it.

 

Ity seems pretty accurate to me...but I've never flown anything with that much power, so my view is strictly subjective.

 

If you say something isn't modeled correctly (and it may not be) some specifics and data would be helpful.

[Anatoli-Kagari9]

I'm still trying to find out it this effect is realistic, not the obvious fact that there must be a deflected slipstream washing the downwind wing, but rather that it's lift and drag generation can overcome the effects of a strong x-wind on the tail...

 

I could at least accept it could be true for a tiny little moment as you release brakes and start rolling, because the slipstream speed is nearing it's maximum value, but after a few seconds, with the aircraft gaining speed, I strongly believe the weathercock effect would be more important.

 

One thing is for sure - if you do not use flaps, and smoothly apply throttle, it is easier to control the aircraft during the takeoff run.

 

Been trying with increasing x-wind values, to find the moment when the wind component actually overtakes that deflected slipstream effect, but so far didn't succeed... I believe Yo-Yo also mentioned a possible problem with the wind modeling, so, maybe a fix in one of the next patches will make it more plausible, but it had to affect only prop aircraft, becaus eif you try these same takeoffs in any of the jets, they'll behave as supposed, weathercoking, and requiring a good deal of downwind rudder and maybe into the wind aileron when possible.

 

Personaly, I still find it difficult to believe the way it is presently modeled is realistic... But I have never flown a real prop aircraft, even less a powerful taildragger, so....

 

As a glider pilot my life is a lot simpler... well... not exactly, but for other reasons :-)

Edited November 6, 2014 by jcomm

[Razgriz1]

The key is: KEEP THE TAIL WHEEL ON THE GROUND and the STICK FULL BACKWARDS up until about 100mph.. If you try to raise the tail before, when you have not enough rudder and aileron authority, it's going to hurt.

 

 

50m/s take off

 

http://forums.eagle.ru/showpost.php?p=2221266&postcount=5

 

This, it took me a lot of tries to take off and when I managed to do it was because of this. I also increased throttle slower, but for me the key was to keep the tail on the ground.

[HotTom]

I also increased throttle slower, but for me the key was to keep the tail on the ground.

 

That's exactly what the manual says to do: Keep the tail on the ground until you have rudder authority and have enough speed to lift off (Page 130) and it works! Amazing, huh? :pilotfly:

[Anatoli-Kagari9]

@HoTom,

 

it's not the technique that is being discussed in this last posts, although it certainly matters, but rather the simulation of an effect that, while it makes sense to be modeled and even elevates IMO the level of detail of DCS's flight dynamics model, can also present some problems, even to rw pilot's.

 

No matter what sources you search for in the Internet, books, aviation syllabus, some very well credited like "Principles of Flight", ..., you will always find the references to the usual takeoff procedure under crosswind.

 

1) On crosswind takeoffs, on any aircraft, single or multi-prop aircraft included, the tendency will be for the aircraft to turn into the wind, requiring opposite ( downwind ) rudder, and even..

2) whenever possible, aileron into the wind.

 

Of course taildraggers are even trickier due to their many features from the location of the CoG relative to the main gear, to the fact that p-factor plays an even bigger role etc...

 

Now, if you takeoff on a powerful taildragger, with a strong wind component from you left, the wind, and the prop effects, will sum up to give you quite a tricky initial takeoff run ride. You may have to apply power smoothly, be prepared to counter the natural tendency of the aircraft to turn it's nose upwind, helped even more by the combination of the prop effects, admiting you're flying a CW rotating prop aircraft, like the p51d, or the Dora.

 

Now, In DCS, with the present release, if you do a test, specially if you takeoff with flaps, you will find yourself fighting to avoid the aircraft leaving the runway downwind side ( through the right, in this case in which the wind is blowing from your left side ).

 

This is counter-intuitive, and something I have never seen referred in any book or internet text, nor heard from conversations with my fellow prop pilots ( I am a glider pilot, with SSG and SLG in my license, but those work as supposed with additional interesting effects because the prop is way above the CoG... ).

 

I can't say for sure it is wrong, but I certainly think it is overdone. At most I agree that under such circumstances this effect of the deflected propwash, plus the drag from the right aileron when you apply aileron into the wind during takeoff, can shorten the wind effect, but certainly not overcome it...

 

Then again, not being a prop pilot, I can't say from my own experience... But there are, among us, experienced pilots and even aeronautical engineers, like effte, who certainly know what they're talking about...

Edited November 6, 2014 by jcomm

[BitMaster]

I havent read the last few posts, it may have been covered there, but to make sure it has been said and understood, regardless of how DCS handles it, in RL the aircraft ( or it's nose if you call it that way around ) will steer INTO the wind until centered UNLESS you take countermeasures. The slower you accelerate the worse the effect over time and further off course you get. While applying power quicker to a firm blast you will force the tail to listen to what the prop says rather than what the wind says. The faster you get while running down the tarmac the less the wind effects you in deg/sec.

 

Keep some pressure on the aileron from where the wind comes from to lower the surface and thus have the wind press it down and provide more tracking instead of grinding sideways over the tarmac, also, with speed this is less important up to almost centered stick before lift off.

 

Again, the wind will push your tail around like a Cock gets swirreled around on the church tower when the wind blows, it's a like an arrow in the wind,

it will always have the part with the highest drag at the rear. in our case, the tail feathers.

 

I have never payed attention to were the wind comes from in DCS as I check my nose and what it does and have no problems with the Pony whatsoever in take-off in any condition or configuration.

 

Bit

[zoomie36]

This gentleman, is called, opening up a can of worms ;)

 

Took quite a few take offs before I had a succesfull take off. It takes so long to restart I don't want to practice it again..

 

As for realism, i crew on helicopters, so much easier taking off into wind :)