Fleet grounded at 7kts??

[XL319]

I had a flight booked at my local flight school. The TAF read 30016kt 9999 FEW031 BECMG 1719 28003. The METAR was 30007KT with the runway being 231 degree's. The school would not fly. I asked why they would not fly as the wind is 7KT's forcast to decrease and they said the wiond direction is dangerous being right across the runway. I couldn't beleive what i was hearing. A C152 has a demonstrated Xwind landing of 15KT's.
I was somewhat bemused as to why they would not fly.
Later checked and the wind went down to 29002KT:eek:

[mad_jock]

Sounds like an excuse to cancel.

It could be multiple reasons why they wanted to cancel you and a 5 knt x-wind wasn't one of them.

[Joe'le'Toff]

Egnv?

Cfs?

[FREDAcheck]

Well I know some schools won't let their planes out if the crosswind is over the demonstrated limit for the plane, but 7kt? Only for low-hour students with no crosswind experience, perhaps? Shurely shome mistake (or really another reason to cancel).

[gcolyer]

Well the TAF was saying 16kts

[flyingphil1]

I always say "when in doubt .. leave it out!" however 7knots would have been good for some relatively easy crosswind landing practice. I think you should talk to them again!

[flyingphil1]

sorry ...I didn’t read properly.. if the cross wind could have been 16 knots which was, according to the TAF, you can hardly blame the school .. apologies and promise to read more carefully in the future.

[Rod1]

Get a share and save the pain.

Rod1

[Whirlybird]

the wind is 7KT's forcast to decrease
According to the TAF, it wasn't forecast to decrease until after 5pm, which is after dark at this time of year. So that can be disregarded. The TAF reckoned the wind would be 16kts, and around 30 degrees off the runway heading....actually probably more like 35 degrees in reality, as the wind direction is true, the runway direction magnetic. You don't say how much experience you have, but that's a reasonable crosswind, especially for a low hours pilot. And forecasts are not that precise - suppose the wind increased to 20kts, and backed to 290 (and it did back, didn't it?). Not a lot of change, but now you have a strong wind by most people's standards, straight across the runway, and out of the limits of both what's stated for the C152, and more importantly, the limits for many pilots.

I think the school was being cautious, but not overly so.

[flyingphil1]

Hi Whirlly .. am I missing something ? is the offset not 70 degrees? If so would that not make 100% of the crosswind and officially beyond the limits of a 150? Anyway I have heard of one airfield |(2 people swear this is true) training in 40 knot plus crosswinds?!! The CFI was 35,000 hours but I find 25 knots very demanding and have 500 hours in 150s but even so rermind myself I'm still a relative novice and leave the heroics for more able pilots.

[matelot]

Did the METAR come from your own field, or another? If so, how far away? Just because it was 7kts one minute, doesn't mean you won't get veering shear and an increase the next.

The TAF forecast 16kts right on the beam (300 - 230 = 70 deg.) Yes, it may have been OK for an instructor, but you may have done a short flight and then got completely caught out.

Having said that, I don't know what your status is (hours/stude et al).

Lightish winds not as forecast is... sod's law. A meaningful discussion with the one who made the decision is often beneficial to learn why people make the decisions they do.

[smarthawke]

It may sound a bit pedantic but I think you'll find the C152 max demonstrated cross wind limit is 15mph not knots (ie 12kts or so).

It would make for an interesting insurance claim if the TAF/METARs exceeded the max demonstrated limit and an aircraft was damaged - even if it wasn't as a result of the cross wind.

Years ago someone reckoned on another forum the max demonstrated cross wind limit was set on the day of the FAA-observed flight test so could only be as much as the wind was blowing on the day - doh!

[XL319]

I understand people's issues here. Remember the TAF always forcasts the worst case scenario for the period indicated. The METAR was 7KTS for 1 1/2 hours as i was watching it. It never went over 12KTS.

I think the FTO was being very over cautious. At the end of the day its their aircraft, but on many occassions the TAF has been wrong and updated as was the case on sunday in Manchester.

I've landed in 15KT crosswinds....it's good practice for me

[Whirlybird]

Hi Whirlly .. am I missing something ? is the offset not 70 degrees?

The only thing you're missing is that Whirly hasn't yet recovered from the effects of a rather good New Year's Eve and therefore can't do simple arithmatic! ;)

[matelot]

Do those things with the whirly bits on top ever experience crosswinds on t/o or landing? Can't they always point into wind and in reality don't even know what a crosswind is? :p

[silverelise]

Years ago someone reckoned on another forum the max demonstrated cross wind limit was set on the day of the FAA-observed flight test so could only be as much as the wind was blowing on the day - doh!
That's correct isn't it?
Shirley the "cross wind limit" is the maximum demonstrated cross wind tested during the aircraft's certification process???:hmm:

[flyingphil1]

I fly a 150 aerobat ... have just checked the P.O.H. and ...... there is no cross-wind limit stated!!! Unless I'm also suffering from ex-party syndrome (well done Whirly) and missed it I may take my personal limit to 40 knots crosswind too (Ok not really able ) .. are there any threads on this new tax on aviation fuel which may prematurely end my flying hobby? ............anyone for tennis?

[Gertrude the Wombat]

40 knots crosswind
Tried to go flying on Friday, gave up because of crosswind, instructor landed and that was that.

Then the instructor told me about the time he had to land in a 55kt crosswind. Had to, because the aeroplane (a Shackleton which was on an S&R mission but became a victim itself) had become broken such that they only had one go at putting it down.

He says they took out just one row of runway lights and considered it a good landing!

[flyingphil1]

instructor told me about the time he had to land in a 55kt crosswind
any increase? I have landed in a 50 knot but that was a 747 and someone else P1!!!

[muffin]

Do those things with the whirly bits on top ever experience crosswinds on t/o or landing? Can't they always point into wind and in reality don't even know what a crosswind is?

Yes they do. Actually you always try to land and take off into wind which is normally easy. However, if the site restricts you it is quite possible to do so out of wind but you have to be careful as it is trickier. The crosswind limit is actually determined by the amount of cyclic authority available, as you obviously have to be stationary as you let it down on to the ground. If you don't have enough sideways cyclic control available to hold it in one place as you touch down, then you have to turn into wind where the control range availability is much greater.

[xraf]

any increase? I have landed in a 50 knot but that was a 747 and someone else P1!!!

Oh yes… no problem. I’ve landed on one wheel, having had the others shot off, in a 200kt, 90 degree crosswind on top of a Tsunami wave, avoiding the gaping crack of a huge earthquake to the left and wake vortex from the Space Shuttle on the right………………………………in a Tomahawk.............with asymetric flap………......Twice that day!

If you tell studes today that........they'll never believe you:E

[flyingphil1]

If you tell studes today that........they'll never believe you:E [/FONT][/COLOR][/SIZE]
They don't know they're born!!!
However .... I know someone who can beat that claim ..... where are you Ferryair .? come in ...Ferryair......Ferryair?

[Whirlybird]

matelot asked:
"Do those things with the whirly bits on top ever experience crosswinds on t/o or landing? Can't they always point into wind and in reality don't even know what a crosswind is?"

And muffin replied:
"Yes they do. Actually you always try to land and take off into wind which is normally easy. However, if the site restricts you it is quite possible to do so out of wind but you have to be careful as it is trickier. The crosswind limit is actually determined by the amount of cyclic authority available, as you obviously have to be stationary as you let it down on to the ground. If you don't have enough sideways cyclic control available to hold it in one place as you touch down, then you have to turn into wind where the control range availability is much greater."

You also have to consider the effects of the wind on the tail rotor. If you're landing with a crosswind from the left, you can get "tail rotor breakaway", which roughly means the tail rotor stops working properly, so that the pedals won't keep you straight! I always thought this was LTE (loss of tail rotor effectiveness), but I've recently been told the two phenomena are slightly different...for those who understand about this or care. The R22 doesn't seem to suffer from this much, and I've never experienced it. But I've been told that it can definitely be a problem in other helicopters. So yes, as Muffin said, you always try to land into wind. However, you can make your approach crosswind, and then turn into wind as you come to a hover...which you can't do with f/w really!

You also need to be careful starting up in a strong crosswind, as you can get blade sailing and chop off your tail! The direction the helicopter is facing and the way the rotor blades turn makes a difference as to whether this happens, but if I think about that too much my head hurts.

Anyway, to avoid all these nasty unpleasantnesses, and having to work out the likelihood of them occurring, we hover-lovers take off and land into wind if we can. :ok: And why not? After all, we don't need runways. :ok: :ok: :ok:

[SkyHawk-N]

any increase? I have landed in a 50 knot but that was a 747 and someone else P1!!!

50 knot crosswind? that's easy in a Cessna! Just land ACROSS the runway, simple :ok:

[XL319]

Surely we should plan to forecasts, and evaluate the weather in realtime. If the club had said the forecasts show the crosswind component outwith the limits of the aircraft and or yourself during the morning, then thats fair.They shouldn't say no flying until the booking time comes up. Due to the nature of the weather things change! Warning you that its highly unlikely is both good practice and fair.

If you however wait until your booking time and the wind has died to a mere 7knots crosswind component and they are happy to lend you an aircraft with that in mind, one should be able too.

Not hiring because a forecast said it could have been 16 knots is crazy. I had a perfect example last week.

I fly from a private strip in Scotland, wind was forecast 18knots cross wind component at mid-day, decaying to approx 12 by tea time. I thought 'oh bugger' no flying for me and went out to the airfield at 1pm to tidy the hangar. The wind was approx 5 knots across the runway and the trend to decay was still forecast. Incedentally our strip is approx 5miles from a major airport which also had the same wind conditions.

Sounds like some club busy-body taking things too literally. Ie a jobsworth who believes because a forecast is made at 3.30am in the morning it must be abided by all day. . . things change. The chaps in the met office agree and are always on the end of the phone . . . call them and look at your windsock!

Exactly my point Capt Flash :ok:

[PicMas]

Regarding max. demonstrated - thats what it is: demonstrated.
Furthermore, for certification the max demonstrated is completed without any corrective action ie. sideslip or otherwise cross control input.

It should thus be an easy task to land an aircraft above the max demonstrated x-wind component.

[HR200]

I have the same problem at EGNM. Even when the weather seems fine and nothing serious on the TAF. They are good with excuses.

Im a PPL so, i hire them out, they dont let us go if the vis is less than 15k, and if the crosswind component is more than 14kt, they get very funny bout it, even though the Robin limit is 18kt.

They are so expensive and find any excuse not to let you go. I haven't flown for 4 weeks now.

I no you have to be safe, but they take the biscuit sometimes, I think if the weather is in safe limits of the aircraft, pilot, and within the qualification of the licence, I don't see a problem.

[dublinpilot]

14kt crosswind is not an unreasonable club imposed limit for low hour pilots, or low currency pilots.

I'll quite happily accept a higher crosswind, but not if I haven't flown in the last month. I find that the ability to deal with strong crosswinds is one of the first skills to be hit by a lack of currency.

Again, 15km viz is not unreasonable for a lower hour/low currency pilot who is navigating by DR in an area that they are not familiar with. Certainly 10km by DR in an unfamiliar area isn't much fun, if you're trying to avoid controlled airspace etc. So 15km gives a reasonable margin for a low hour/currency pilot.

Obviously as a pilots experience and currency improves, they need to be able to remove these restrictions (by proving their ability with an instructor onboad, and maintaining currency), but as a general club rule, I don't think these figures are unreasonable.

dp

[AC-DC]

any increase? I have landed in a 50 knot but that was a 747 and someone else P1!!!

I was flying at 40kts headwind at FL065. Does it count?:)

[tmmorris]

Oh come on, I was flying in a 40kt headwind today at 2000ft! Made the old Robin seem a bit sluggish...

The real fun was my best crosswind landing to date - 20kt crosswind, directly across the runway. The Robin has a demonstrated max of 22kt and I can see why. This was also my first wing down landing in anger - I was always taught to crab but to be honest the wing down landing was a fantastic revelation. But at 20kt crosswind I had pretty much full rudder deflection, so I can see why 22kt was the max!

Tim

[172driver]

Landed a few times in 35-40 kts - pretty much straight down the rwy, I hasten to add, however ! Actually, the taxiing is the interesting part in this kind of wx :eek:

Where I learned to fly and where I fly now, quite a bit of wind is pretty much the norm. I find it sad and not very productive, that FTOs don't make use of a benign x-wind situation to teach their students how to handle the a/c. In the real world, you will land in x-wind and it's better to be trained for that than doing the trainig on your, errr, first x-wind landing as PIC. :=

In any case, all POH's I've ever seen carry a note underneath the 'Max demonstrated crosswind' saying something to the effect 'the above value does not constitute a limitation'.

PS: I have, to agree with some others here that probably the best x-wind a/c I've ever flown is the Robin. Amazing what this thing can handle !

[Gertrude the Wombat]

if the crosswind component is more than 14kt, they get very funny bout it, even though the Robin limit is 18kt.

It's the pilot's limit that matters.

Where I fly they'd let me up with a 15kt crosswind according to the rules ... but there's no way I'd take off in that.

(I go flying for fun. That wouldn't be fun, even if I did manage not to bend the aircraft.)

[xraf]

What has so far been missing from this discussion are the ever-present health and safety and legal retribution considerations that are associated with all businesses these days.

i.e. If the TAF forecasts a wind increase and the student (or whoever) has a crash/incident etc, during the following 'investigation' the authorising instructor and ultimately the school will be in trouble for ignoring it. This will be the case even if the wind at the time of the accident was less than forecast, less than the limits etc etc.

Regardless of the fact that every pilot knows meteorology is about as close to witchcraft you can get without actually buying a broom and a black cat!:ugh: Civillian courts, juries and lay people generally still assume its all very predictable, especially as the highly trained 'Met man' says so!

Hence, 'Beware the lawyers':= has to be the attitude of the day and so we can expect in aviation as in every other walk of life a continually more conservative attitude to, well, pretty much everything!

We used to say 'If you believe a Met report I can sell you the Brooklyn bridge' these days its more like 'If you dont believe your Met report, you'll wind up swinging in the wind underneath the Brooklyn bridge!'

Regards to all
Xraf:ok:

[S-Works]

It may sound a bit pedantic but I think you'll find the C152 max demonstrated cross wind limit is 15mph not knots (ie 12kts or so).
It would make for an interesting insurance claim if the TAF/METARs exceeded the max demonstrated limit and an aircraft was damaged - even if it wasn't as a result of the cross wind.
Years ago someone reckoned on another forum the max demonstrated cross wind limit was set on the day of the FAA-observed flight test so could only be as much as the wind was blowing on the day - doh!

It may also be pedantic but the 152 does not have a crosswind LIMIT it has a demonstarted crosswird component NOT a LIMIT. And my POH says 17 KNOTS..... DEMONSTRATED.

[tmmorris]

True that it's demonstrated not limiting, though I wonder what a court would say if you had been advised that no test pilot had demonstrated a capability beyond X knots and you exceeded that and damaged the aircraft.

I was taught C152 was 12kts, so that tallies with 15mph quoted above. It's a big issue with my home base - runway 01/19, typical wind 240/10-15: it was fine when runway 06/24 was still open...

Tim

[Flyin'Dutch']

I had a flight booked at my local flight school. The TAF read 30016kt 9999 FEW031 BECMG 1719 28003. The METAR was 30007KT with the runway being 231 degree's. The school would not fly. I asked why they would not fly as the wind is 7KT's forcast to decrease and they said the wiond direction is dangerous being right across the runway. I couldn't beleive what i was hearing. A C152 has a demonstrated Xwind landing of 15KT's.
I was somewhat bemused as to why they would not fly.
Later checked and the wind went down to 29002KT:eek:


XL, you don't make it clear at what stage of the game you are.

Not flying because of that wind and crosswind component does not seem to make a lot of sense as others have said unless you are an early solo pilot who needs to do more solo circuit consolidation.

The new year looks promising, only 5 days old and I am already agreeing with Bose-X, what is the world coming to!

It may also be pedantic but the 152 does not have a crosswind LIMIT it has a demonstarted crosswird component NOT a LIMIT. And my POH says 17 KNOTS..... DEMONSTRATED.

There are a gazillion threads on crosswinds etc.

The demonstrated crosswind is exactly that. It ain't a limit, it is nothing legal other than a certification requirement.

At best it is some guidance.

Happy (crosswind) landings.

[S-Works]

True that it's demonstrated not limiting, though I wonder what a court would say if you had been advised that no test pilot had demonstrated a capability beyond X knots and you exceeded that and damaged the aircraft.
I was taught C152 was 12kts, so that tallies with 15mph quoted above. It's a big issue with my home base - runway 01/19, typical wind 240/10-15: it was fine when runway 06/24 was still open...
Tim
Yadda yadda, what is with Brits always hiding behind what a court might say! You will be talking with a yank twang next and never leaving the house in case you get taken to court for farting in the street.
There is no crosswind limit on a 152. The demontsrated componed was just what was available to the test pilot on the day. Do you really think they sat and waited for a mega windy day?
If you are current and capable you can put an aircraft down way beyond the "demonstrated" cross wind. When I had my 152 I put it down in 30+ kts straight accross the runway on a regular basis and still had rudder authourity. I still do the same with my 172 as the runway still points the same way.
What a dull life we would lead if always fearfull of the scumbag lawyers! Its not a police state its a laywer state.

[HGFC1]

Bose - are you sure you weren't reading your POH for the 172* or a PA28? The demonstrated crosswind component (which Cessna say should not be considered limiting) for a C152 is 12, TWELVE knots NOT 17! 17kts is the limit for a PA28 and 20kts for a DA40.
* I have never seen the POH for, or flown a 172 so cannot give the figure in the POH and don't have access to one to check but I am absolutely certain that it is 12 knots for the C152 having not only read the POH but also recently been chatting to the CFI about it and he has thousands of hours in 152s.

[XL319]

XL, you don't make it clear at what stage of the game you are.

Not flying because of that wind and crosswind component does not seem to make a lot of sense as others have said unless you are an early solo pilot who needs to do more solo circuit consolidation.

The new year looks promising, only 5 days old and I am already agreeing with Bose-X, what is the world coming to!



There are a gazillion threads on crosswinds etc.

The demonstrated crosswind is exactly that. It ain't a limit, it is nothing legal other than a certification requirement.

At best it is some guidance.

Happy (crosswind) landings.

I have a fair bit of experience. Landed a 152 in a lot worse than 15....the club had stopped flying to everyone. At the end of the day it's their airctaft and my licence so sods law

[S-Works]

Bose - are you sure you weren't reading your POH for the 172* or a PA28? The demonstrated crosswind component (which Cessna say should not be considered limiting) for a C152 is 12, TWELVE knots NOT 17! 17kts is the limit for a PA28 and 20kts for a DA40.
* I have never seen the POH for, or flown a 172 so cannot give the figure in the POH and don't have access to one to check but I am absolutely certain that it is 12 knots for the C152 having not only read the POH but also recently been chatting to the CFI about it and he has thousands of hours in 152s.

My 152 manual says 17kts. I have more than a thousand on hours on that aircraft alone. But whatever figure it may be it still does not say LIMIT. I was merely making a pedantic point. There are enough rules and regulations in aviation without making up more!!1

[formationfoto]

On the subject of rotary cross wind is, as has already been suggested, an issue. This is particularly the case if you have to fit in with the f/w circuit traffic or there are obstructions around the landing are preventing you from approaching into wind. Under these circumstances you are crabbing with the crab angle increasing as you slow down. Side cyclic limits are a factor but so is the tail rotor. This is one area where the R22 seems better than most. Getting onto the ground is not normally a great problem if you do it right. The challenge is then hover taxiing back to dispersal. Try this in something like a Brantly with limited tail rotor effectiveness and it become an interesting exercise once you get past 15 knots or so - particularly in confined areas.

[The Nr Fairy]

I once had an "interesting" time in a B206 (JetRanger) in gusty conditions - with a gusty crosswind from the right, in the hover, when the gust disappeared.
The bootful of left pedal I had (keeping the aircraft pointing where I wanted it, against the crosswind) meant that the gust dissipation led to an instant 90 degree turn to the left before I could catch it (ending up pointing downwind and descending in the process) - so it's not just the arrival of a gust which can cause problems, it's their departure too, and not just for helicopters, I'm sure.

But generally we have it easier that our f/w compatriots because we don't have to land then stop, we stop then land, so there are more options on what we do below 50 or 60 knots.

[Tim_CPL]

Hi Whirlly .. am I missing something ? is the offset not 70 degrees? If so would that not make 100% of the crosswind and officially beyond the limits of a 150? Anyway I have heard of one airfield |(2 people swear this is true) training in 40 knot plus crosswinds?!! The CFI was 35,000 hours but I find 25 knots very demanding and have 500 hours in 150s but even so rermind myself I'm still a relative novice and leave the heroics for more able pilots.

As I am sure you are aware, the max demonstrated x-wind is not an operating limitation, this point has been raised many times in the past. Having said that a 20K direct x-wind would be a demanding situation requiring precise technique and competancy for any pilot....

- Tim

[S-Works]

A 20kt crosswind is not difficult.

An excerpt from my 172 flight manual:

The maximum allowable crosswind velocity is dependent upon pilot capability as well as aircraft limitations. With "average" pilot technique direct crosswinds of 37km/h - 20kts can be handled with safety.

There is no demonstrated crosswind at all in the POH. Flying out of a strip that only has one usable runway most of the winter I often encounter days where the crosswind is much higher than 20kts straight across. Currency and practice count in this situation. Landing at night at our place with these winds is a lot more bum clenching!!!

[IO540]

The other thing is that the reported x/w is measured at the top of quite a tall pole; 10m I think.

So the actual xw seen by the aircraft when about to touch down is a lot less than that reported.

This is why the aircraft normally straightens out by itself, to a large degree or sometimes even all the way to the runway heading, during the flare. Unfortunately, the inertia in yaw eggagerates this effect and one finds that a lot of rudder is needed pretty quickly.

A 20kt genuine x/w is not easy to land in. One needs loads of rudder, loads of opposite aileron, and courage. This would correspond to something like 30kt reported x/w figure.

[tmmorris]

Interesting point about the wind being measured at the top of a pole. Yesterday landing at Cambridge in a C152, the crosswind was gusty and around 20kts. I stuck to it down finals but was 90% sure I was going to have to go around, but in the last 20ft or so things calmed down considerably and in the end it was fine. A wind measured at the top of a pole would have suggested it wasn't possible to land a C152 under those conditions.

[Gertrude the Wombat]

Yesterday landing at Cambridge in a C152, the crosswind was gusty and around 20kts. I stuck to it down finals but was 90% sure I was going to have to go around, but in the last 20ft or so things calmed down considerably
That's normal at Cambridge ... but it's not guaranteed, it doesn't always happen, so being ready for the go-around is definitely the right thing to do!

[tmmorris]

Thankfully the friend I was meeting is a pilot (big stuff) so I didn't feel under any pressure to land if it wasn't safe. He told me afterwards that he'd decided if I went around twice, he would be off home (as would I!)

[9 lives]

Think in terms of "boundary layer". There is the wind speed, and closer to the ground, the earth's boundary layer will begin to have an effect, which will be to slow the wind. Of course, many factors will affect this, so you can't usually quantify these effects. However, they will result in some wind speed reduction very close to the surface. Beware that any topographic "funneling" could cause an opposite effect, but generally, airports are not found where a crosswind funneling effect is fa big problem.

Also, as the aircraft comes into ground effect, the flight controls will be just a bit more effective. Thus, if you can maintain the runway heading with precision down final approach, chances are good that it'll become more easy close to the surface.

[Big Pistons Forever]

As instructor I would like to comment from the other side of the desk.

The OP did not specify who he was talking to when he was refused the chance to fly. Dispatch staff tend to be low experienced individuals and thus are given little descretion. A discussion with the CFI may had generated an exception for you.

On the other hand and at the risk of being rude, maybe they did not think you were good enough. I see discredition applied all time at school where I help out at. Sadly a significant proportion of the rental Pilots only seem to be interested in maintaining their skills to the absolute bare minimum. These pilots don't get the keys if there is any doubt about the conditions. However I have watched a relatively low time PPL get dispatched to a shortish field with a 15 kt 90 degree crosswind. There was not the slightest doubt in any of our minds that he would have any difficulty handling the conditions.

[ChickenHouse]

So much dispute, so little facts.

First, there is a big difference in POHs from different built years. The older POHs of 150 and 172 state only a demonstrated crosswind up to which is has been shown to land safely for an average pilot. Later POH set a clear limit, do not exceed certain crosswind. I remember the SP I took training had a clear limit of, I think it was 17 knots, but the old one I am flying now has this legendary demonstrated sentence instead. Same is true for 152s - the "ordinary" ones have a limit, but the F Aerobats have no sentence limiting crosswind. So, it depends on the correct POH wether it is legal to land and within stated operational limits or not - in the end.

Then we have the question where to fly. I dont know the airfield in question, but had quite some fields where certain wind direction where simply unflyable due to obstacle turbulence.

Last and most important - upon what pilot we are talking? Low time students I would not force into strong crosswind, while high time students should go up to the limits of POH to get the feeling for real crosswind. But all depends on the guesstimate of the FI and his knowledge of the student. Pilots will encounter it later on and it is always better to do with an instructor first ... Or are we talking charter? Then it gets obscure as the flight safety is solely on the discretion of the pilot. And yes, I did landings with up to 35G40 knots crosswind with a C172, but after this I knew I could do if needed, but will do much to avoid it.

[funfly]

You are the student, they are the school.

Listen and learn. :ugh:

[India Four Two]

And yes, I did landings with up to 35G40 knots crosswind with a C172,

With those kind of winds, I would be landing on a taxiway or across the runway.

[piperboy84]

If it's blowing a 20 plus full xwind, I am landing across the runway and onto the grass for the extremely short roll out

[9 lives]

I remember the SP I took training had a clear limit of, I think it was 17 knots, but the old one I am flying now has this legendary demonstrated sentence instead. Same is true for 152s - the "ordinary" ones have a limit, but the F Aerobats have no sentence limiting crosswind. So, it depends on the correct POH wether it is legal to land and within stated operational limits or not - in the end.

I believe this to be not correct;

Unless the crosswind "limitation" is specified in Section 2, limitations (or the earlier format equivalent), there is no limitation. There is a stated demonstrated capability, that is not legally limiting. The pilot may attempt a landing in as great a crosswind as they choose, and be legal.

The prevailing design requirement reads:

Sec. 23.233

Directional stability and control.

(a) There may be no uncontrollable ground or water looping tendency in 90 degree cross winds, up to a wind velocity of 0.2 VS0, at any speed at which the airplane may be expected to be operated on the ground or water.
(b) A landplane must be satisfactorily controllable, without exceptional piloting skill or alertness, in power-off landings at normal landing speed, without using brakes or engine power to maintain a straight path.
(c) The airplane must have adequate directional control during taxiing.

As can be seen, the strength of the crosswind which must be demonstrated is based upon the stall speed. But also note that this "demonstrated" value is based piloting without exceptional skill or alertness.

It is also noteworthy that the design requirements for limitations do not mention crosswinds at all - there is no requirement to state a crosswind "limitation".

Sec. 23.1583

Operating limitations.

(a) Airspeed limitations. Information necessary for the marking of the airspeed limits on the
indicator as required in Sec. 23.1545 must be furnished, including VA and VLO. The significance of each limitation and of the color coding must be explained.
(b) Powerplant limitations. Information must be furnished to explain the powerplant limitations and to allow marking the instruments under Sec. 23.1549.
(c) Weight. The airplane flight manual must include--
(1) The maximum weight;
(2) The empty weight and center of gravity location;
(3) The useful load; and
(4) The composition of the useful load, including the total weight of fuel and oil with full tanks.
(d) Load distribution. The established center of gravity limits must be furnished. If the available loading space is adequately placarded or arranged so that no reasonable distribution of the useful load listed in paragraph (c) of this section will result in a center of gravity outside of the stated limits, the Airplane Flight Manual (where required) need not include any information other than the statement of center of gravity limits. In other cases, the manual must include enough information to indicate loading combinations that will keep the center of gravity within established limits.
(e) Maneuvers . The following authorized maneuvers, appropriate airspeed limitations, and unauthorized maneuvers must be furnished as prescribed in this section.
(1) Normal category airplanes. For normal category airplanes, acrobatic maneuvers, including spins, are unauthorized. If the airplane has been shown to be "characteristically incapable of spinning" under Sec. 23.221(d), a statement to this effect must be entered. Other normal category airplanes must be placarded against spins.
(2) Utility category airplanes. For utility category airplanes, authorized maneuvers shown in the type flight tests must be furnished, together with recommended entry speeds. No other maneuver is authorized. If the airplane has been shown to be "characteristically incapable of spinning" under Sec. 23.221(d), a statement to this effect must be entered.
(3) Acrobatic category airplanes. For acrobatic category airplanes, the approved flight maneuvers shown in the type flight tests must be included, together with recommended entry speeds. A placard listing the use of the controls required to recover from spinning maneuvers must be in the cockpit.
(f) Flight load factor. The positive limit load factors, in g's, must be furnished.
(g) Flight crew. If a flight crew of more than one is required for safety, the number and functions of the minimum flight crew must be furnished.
(h) Kinds of operation. The kinds of operation (such as VFR, IFR, day, or night) in which the airplane may or may not be used, and the meteorological conditions under which it may or may not be used, must be furnished. Any installed equipment that affects any operating limitation must be listed and identified as to operational function.
(i) If the unusable fuel supply in any tank exceeds five percent of the tank capacity, or one gallon, whichever is greater, information, showing that the fuel remaining in the tank when the quantity indicator reads "zero" cannot be safely used in flight, must be furnished. This information must be in the Airplane Flight Manual (if provided) and on a placard.

The owner of the aircraft may have more restrictive rules, and that is their prerogative as the owner, but the pilot is legal to attempt a landing at any crosswind value (not exceeding a limitation), and the aircraft would be insured to do that, as long as the pilot was duly authorized to fly it.

Yes, mechanical turbulence can greatly affect the capability of an aircraft and pilot, and acting as a crosswind, even more.

I have taken off my 150 in 37G43 knots at a 45 degree angle for an emergency flight. I did not attempt to land back on the same runway, I selected a different aerodrome, with the runway right into the wind.

[India Four Two]

Sec. 23.233

Directional stability and control.

(a) There may be no uncontrollable ground or water looping tendency in 90 degree cross winds, up to a wind velocity of 0.2 VS0,
ST,

Which country's regulations are you quoting?

That 0.2 Vso value looks like the reason for the ludicrously-low demonstrated cross-wind value of my club's DG-1000S:
The demonstrated crosswind velocity is 15 km/h (8 kts.) according to the airworthiness requirements.DG FLugzeugbau hedge their bets a bit later in the manual:
Due to the towhook position being in the middle of the fuselage and the excellent effectiveness of the ailerons and rudder, the possibility of wing dropping or ground loops, even on a slowly accelerating aerotow is reduced. Take-off with strong crosswind is possible.

[MrAverage]

Since tmmorris resurrected an 8 year old thread it is unlikely the OP will see this. However, another interpretation is that this could have been his first night circuit session on a short narrow runway (it was night after all) in which case the decision was wise.................

[MrAverage]

Correction, it could have been night...........

[phiggsbroadband]

If you are flying from an crummy airfield with only one runway, what do you expect....
Join a club at a better airfield; with three runways in a triangular layout.

[tmmorris]

Sorry for the resurrection... I was looking for the sort of thing Step Turn posted, because I'd read the POH carefully to see the wording on the 'limit'. Thanks for that!

[ETOPS]

piloting without exceptional skill or alertness.


Do they mean me :eek:

[9 lives]

piloting without exceptional skill or alertness. Do they mean me :eek:

Certainly not ETOPS! ;)

What they mean is that when I as the demonstration test pilot fly the plane, If I use exceptional skill or alertness to make the plane do what the requirement says it must - it might not have passed. Another test pilot might come to refly it, and use "regular" skills, and see if they can fly the same maneuver.

This can be a really tough call to be objective. The demonstration test pilot must have lots of experience, but in essence, they are not really supposed to call upon that skill, unless something goes wrong.

ST,

Which country's regulations are you quoting?

I42, That's copied from the latest FAA FAR Part 23, though the wording for that requirement has been largely unchanged since the CAR 3 days.

[India Four Two]

tmmorris,

No need to apologize. Resurrecting an old thread is often better than creating a new one, since readers can see what was posted previously. Often very useful, if the thread was missed before or forgotten about.

[tmmorris]

In a C152 POH I found online (1980 vintage) I see the exact wording is:

maximum demonstrated crosswind velocity 12kts (not a limitation)

Which is pretty clear. Other POHs may vary.

[Jim59]

Further to previous extracts from CS 23 (previously JAR23) which correctly stated that the certifier only has to test to a minimum crosswind component of 0.2 of Vso, if they think that there is a higher limiting figure they should put it in section 2 of the flight manual. I don't think I've ever seen one given.

V107 PARAGRAPH 23.233 DIRECTIONAL STABILITY AND CONTROL
a. Explanation
(1) Crosswind. This regulation establishes the minimum value of crosswind that must be
demonstrated. Since the minimum required value may be far less than the actual capability of the
aeroplane, higher values may be tested at the option of the applicant. The highest 90° crosswind
component tested satisfactorily should be put in the AFM as performance information. If the
demonstrated crosswind is considered limiting, it should be introduced into Section 2 of the AFM.

[PA28181]

IMHO an AT3 (first production as later models may be different), should have a limit applied given it's handling characteristics on the ground