Stalling into wind.

[dobbin1]

I came across some professionally produced instructor briefing notes recently and the briefing for stalling stated that stalls should be done into wind.

I can't think of any reason why the direction of the wind would have any influence on stalling at altitude. Can anyone explain this one to me?

[Genghis the Engineer]

Uses less turf underneath you, so you finish the exercise about the same place you started, thus reducing SA workload?

G

[LAI]

As Genghis says, it is purely a sortie management/S.A. consideration - nothing to do with the actual aerodynamics of the situation (I hope!! :eek:)

[dobbin1]

I hope so too. Seems odd to include it in the brief to a student though.

[LAI]

Maybe so, but I guess if you look at it from the perspective of sending them off in future to do solo GH (including stalls), then it might be a valid airmanship point in the "don't get lost while you're busy flying the perfect stall Bloggs" category!

[GipsyMagpie]

From my training it was so the increase in drift doesn't distract from the core technique. Bit weak though.

[GgW]

Seems odd to include it in the brief to a student though.

You are joking right??

[fireflybob]

Surely from a sortie management point of view it's best if possible to do upper air work upwind of the airfield - of course with controlled airspace constraints this is often not feasible.

Seeing as a lookout turn of either a 180 or two 90s each way is the norm immediately prior to a stall one of these may be a better option wrt to staying upwind and/or in the training area.

That said I generally prefer to teach the pre stall checks into wind since this seems to take a lot longer that the actual stall for the average student.

[RequestAsymmetrics]

Hmm sounds a little bit pedantic... A switched on student eventually works out to pick a slice of horizon which doesn't have them staring into the sun or pointing towards CTA.

[foxmoth]

To me this is something worth mentioning in the briefing as a "consider" point, if you do multiple stalls in a light wind you could actually end up further away from home than you want!

[fireflybob]

Well said, fox mouth, it all depends...

[wantobe]

A brand new student doing stalls crosswind doesn't usually have his/her eyes in the right place to begin with and hence very little directional control.

Entering the stall in a cross wind situation (especially in a stronger wind) makes it difficult for them to keep the aircraft straight and in balance (weather cock). Usually resulting in a wind drop stall.

[bingofuel]

Entering the stall in a cross wind situation (especially in a stronger wind) makes it difficult for them to keep the aircraft straight and in balance (weather cock). Usually resulting in a wind drop stall.

Would you care to expand on this phenomenon?

[Heston]

I bet £5 he wouldn't...

[foxmoth]

Never had that myself - get them to use a cloud to keep straight on, that will normally have the same or similar crosswind that the aircraft has!

[WeeJeem]

I have hazy recollections of hearing this a long time ago, and I vaguely recall that it was ostensibly to minimise the risk - during the transition from the "dropping like a brick through the breeze" phase to the "floating like a cloud on the breeze" phase - of only (un)stalling one of the sticky-out bits and somehow popping into a spin rather than flying out of a stalling. Can't for the life of me remember what the underlying mechanics were meant to be to achieve this, tho :ooh:

Wasn't particularly convinced then, and no more so now.


ETA:

Entering the stall in a cross wind situation (especially in a stronger wind) makes it difficult for them to keep the aircraft straight and in balance (weather cock). Usually resulting in a wind drop stall.

Actually, that rings a bell. That might very well have been the "reason".

[Genghis the Engineer]

An interesting thread this for Freudian slips.

So far I count "Fox Mouth" and " Wind Drop".



On a more technical point, presumably a pilot, particularly an inexperienced one, might well use external references to try and hold the aircraft "straight" when flying with a crosswind thus induce sideslip. Particularly likely, one might assume, at low speeds - thus making a spin more likely.

Thinking out loud, I wonder if this might have been a player in a few stall/spin accidents off base or crosswwind. It would certainly be compatible with the reports about a few fatals.

G

[bingofuel]

GtE

Having read your post and re read the initial comment which I read as 'the crosswind acts on the aircraft at altitude' instead of 'moves with the air mass'
I can now see the original poster may have meant what you have described, the student will try to point at his reference point using rudder and create an out of balance situation, whereas he should be checking the balance ball to remain in balance.

Just shows how important the correct choice of words is in teaching.

[foxmoth]

An interesting thread this for Freudian slips.

So far I count "Fox Mouth" and " Wind Drop".

I think these are not so much Freudian slips as not picking up on an unintended autocorrect, I know that is certainly the normal problem with my own user name!:hmm:

[dobbin1]

I could buy the "ground reference " explanation if we were stalling close to the ground, but if course we don't do that and at 3,000 ft the visual clues from the ground are negligible.

I can see that stalling into wind might keep you from being blown away from the airfield, but this is a bit thin and I don't see why you would mention that on a pre-flight brief.

Surely "wantobe" is a troll.;)

[wantobe]

Yes I'm a troll. And Aircraft do not weathercock into wind, okay suit yourself.

Just to be clear I see it happen everyday, student enters stall crosswind. Tries to set drift with rudder because we are getting blown downwind, aircraft is unbalanced and will always result in a wing drop stall.

[dobbin1]

You see students change their approach to a stall due to the relative movement of the ground 3,000 ft below? And when the student is most likely looking ahead anyway?

All I can say is this is not my experience. At 3,000 ft the movement of a distant horizon is barely perceptible. If your students are getting frequent wing drops during stalling exercises the cause is not keeping the ball in the middle, not the wind.

Aircraft do of course weathercock into wind on the ground. Not at altitude.

[27/09]

Yes I'm a troll. And Aircraft do not weathercock into wind, okay suit yourself. And an instructor to boot. Following on from your statement in an earlier post I presume your were using a bit of sarcasm here. I hope you don't mean to apply the weather cocking statement to an airborne aircraft. If so, you'd better review your P of F.

Just to be clear I see it happen everyday, student enters stall crosswind. Tries to set drift with rudder because we are getting blown downwind, aircraft is unbalanced and will always result in a wing drop stall.I've never seen this in over 4000 hours of instructing. What are you getting the student to use as a reference point? From your earlier post I get the impression you aren't actually telling them where to look. Whose fault is then if they are looking in the wrong place? I always get them to use something on the horizon or at least towards the horizon. Any drift is then imperceptible. Do you not also teach them to check the "ball" is centred?.

[Heston]

Yes I'm a troll. And Aircraft do not weathercock into wind, okay suit yourself.

The only accurate statement you've made so far.

[Runaway Gun]

I recently had a check flight with a CFI and he informed me that he had been practising stalls earlier that day, and it was so windy that he had to point into the wind. I just nodded.

[Tee Emm]

if you do multiple stalls in a light wind you could actually end up further away from home than you want!


Assuming you are flying a light training aircraft type that stalls at 45 knots then multiple stalls should not take you far in terms of distance over the ground.

[dubbleyew eight]

aeroplanes only ever fly into (an apparent) wind.
it is what gives them lift.

only numpties who's mindset is that of a person on the ground would think the way the poster has commented.
once your wheels are off the ground you are flying into the surrounding parcel of air.

you have to wonder these days if people really actually understand anything at the end of their training.

[Hadley Rille]

As a student Stick and Rudder has been the most useful book I've read and I'd recommend it to anyone learning to fly. Chapter 6 Wind Drift covers this subject and Wolfgang explains it really well.

[taybird]

I'm pretty sure the LAA test flight schedule calls for stalls to be carried out into wind.
The reason I prefer into wind (although not exclusively so) is that any head-on gusts will lead to symmetric effects on the aeroplane, whereas a gust from the side can lead to different lift effects as well as potential yaw, which will lead to a stall at a higher indicated air speed and a more likely wind drop.

[MarcK]

The reason I prefer into wind (although not exclusively so) is that any head-on gusts will lead to symmetric effects on the aeroplane, whereas a gust from the side can lead to different lift effects as well as potential yaw, which will lead to a stall at a higher indicated air speed and a more likely wind drop.
You get a lot of gusts at 3000' in your part of the world, do you?

[fireflybob]

Have to say this thread is descending into something farcical now - must make sure I don't stall near a time vortex.....

[taybird]

Mature, MarcK.
It's interesting that you think you know what height I stall at. I simply offered my personal thoughts based on my own experience. If you choose to speak to your students in the same way as you just responded to me, I feel sorry for them.
I have found the comments regarding managing displacement in strong winds during stalling to be valid. The first time I stalled a C172, a long time ago, we were actually moving backwards, with a negative value for the ground speed.

[MarcK]

I understand about stalling "into the wind" in an effort to keep yourself in the training area. I don't understand why some posters think it actually has an effect on the aircraft behavior with respect to the air.

[taybird]

Have you ever had to correct the aircraft attitude in level flight because a gus has tipped you one way or another?
How much more likely is a gusty wind to tip you up if it's from the side as opposed to on the nose? Think about managing a final approach to land with a crosswind as opposed to straight down the slot.

If you're telling me that you don't ever have to correct for a gust in flight, you are telling fibs. A momentary upset by a crosswind gust causes a roll in the aircraft. I'm pretty sure I don't need to explain how this might lead to a wing drop and earlier stall likelihood when flying in less than smooth crosswind conditions.

That said, if you have a better explanation of why this theory is wrong, I would be interested in your thoughts. Learning is much better than being sarcastic and rude to your colleagues.

[MarcK]

I've not seen crosswind gusts in level flight at altitude. I have seen thermals, which come from below. Put a wing in one and that wing will rise. Talk to a glider pilot. Where do you think these crosswind gusts come from? And where did you learn basic meteorology?

[CISTRS]

With much trepidation, I comment:

Do we really need reminding about the basic effect of wind on an aircraft in flight? The differences between course, track, heading, ground speed, indicated airspeed? Is this what we get when we rely exclusively on GPS and nav software? Never happened in the whizzwheel days.

http://i1227.photobucket.com/albums/ee422/pimlican/WindDrift_zpsa1857f31.gif (http://s1227.photobucket.com/user/pimlican/media/WindDrift_zpsa1857f31.gif.html)

We do not lay off the drift with rudder, and skid around the sky. We fly with the ball in the middle, wings level.

Only exceptions would be:
sideslipping to lose altitude without increasing speed
crosswind landings, especially through a wind gradient.

Straight stalls take place with reference to the parcel of air moving over the ground. At training altitude, wind speed and direction are factors only for positioning over the ground.

Before doing the exercise, don't forget HASELL, clearance turns and check for time vortices. :ok:

[taybird]

MarcK - "at altitude"
Says it all - you obviously missed what I said before. I don't carry out final approaches at altitude, and neither do I necessarily explore slow flight and the incipient stall at altitude.

I teach Met at ATPL level.

My suggestion was that a potential reason for why some people are told to stall into wind is because of this. The fact that in training, we tend to operate at higher altitudes doesn't mean that everyone in the world carries out stalling at 5000'. The last time I looked at a stall (not in training) I was at 1500', lowest was at 800'.

It's clear that everyone has their own way of carrying out stalls, and of teaching them too. The fact that some people insist on stalling into wind doesn't make the lesson any less valid, does it?

[WeeJeem]

I've not seen crosswind gusts in level flight at altitude.

We called it CAT, back in the day. :cool:

[WeeJeem]

I've not seen crosswind gusts in level flight at altitude.

We called it CAT, back in the day. :cool:
Unless, of course, it wasn't CAT but was actually wave turbulence, in which case we called it "wave turbulence".

[Cows getting bigger]

I can't say I've previously thought about this. I think there may be a little bit of mileage in the reference point argument, especially when demonstrating the symptoms of an impending stall (yaw at high AOA). Most of the other stuff, in my opinion, is nonsense.

I think I'll keep using HASELL without the addition of a W. :)

[Centaurus]

Before doing the exercise, don't forget HASELL, clearance turns HASELL? What is HASELL? I checked through my Boeing 737 flight crew training manual which covers stall practice and not word about HASELL. :D

[CISTRS]

HASELL? What is HASELL? I checked through my Boeing 737 flight crew training manual which covers stall practice and not word about HASELL

Cast your mind back to your pre-PPL days:

Height
Airframe
Security
Engine
Location
Lookout

No magenta lines....