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Ringway Flyer
13th Jan 2005, 18:27
Just been to Dublin on a short break from MAN. We were a bit concerned hearing about gusts to 60 knots a fair way off the runway heading forecast. Being used to limits of around 18 knots in a PA28, I would be interested in knowing what the limits are for commercial aircraft? We went Ryanair on a 1980s 737-200....

Georgeablelovehowindia
13th Jan 2005, 20:15
It's around 30 knots for most jet transport aircraft, including the 737.

The Greaser
14th Jan 2005, 07:41
35 knots for the 737, in my company anyway.

BOAC
14th Jan 2005, 09:30
A manufacturer will 'demonstrate' crosswind landings on a new type ie the company test pilots will 'explore' the practical limits during test flying.

This limit will be the maximum that most companies would consider using due to liability issues. I think the 737 has been 'demonstrated' by Boeing at 40kts on a dry runway, and this indeed was the BA limit for captains (when I left last year, anyway). My current operator specifies 35kts dry.

There is no reason to expect that it would be 'impossible' nor unsafe to exceed this limit. It is just that Boeing will only 'guarantee' this product up to 40kts.

The limits are nearly always reduced for wet, narrow and contaminated runways. Normally co-pilots have lower crosswind limits. Also it is common practice to consider only the steady crosswind rather than the gusts in analysing the situation, although there is always a subjective input in that process!

I think that's about all I know. HIH:D

omnidirectional
14th Jan 2005, 09:33
Its 40 knots in my company on 737

Ringway Flyer
15th Jan 2005, 06:25
Thanks for the information. Further to the cross wind question, a number of missed approaches were noted at MAN during the windy weather owing to wind shear. What is the decision height for, say 737, and how is the go-around initiated by the aircraft? (The comment 'the aircraft decided to go-around' was heard quite often), so I assume the computer took the decision?
Just curious.....

batty
15th Jan 2005, 08:05
The decision height varies according to the type of approach being flown ie Precision / Non Precision,the airfield in use, the category of aircraft being flown and sometimes the experience of the pilot. The decision to land or not can be made at any time it isn't just made at the decision height. The decision height is the point at which if your not visual and within the landing criteria you have to go around.

Your not totaly commited to a landing until the speedbrakes pop up on touchdown ie you can still go around below decision. Should the aircraft become unstable at any stage a go around should be initiated thats above and below decision.

The go around is normaly initiated by the pilot pressing the TOGA switches and rotating the aircraft into the climb. The go around is normaly flown by the pilot but on occasion it can be flown by the aircraft depending on the autopilot set up but even in this case the aircraft doesnt make the decision its the pilots.

We have to do a little work you know..;)

SVK
18th Jan 2005, 14:21
The go around is normaly initiated by the pilot pressing the TOGA switches and rotating the aircraft into the climb. The go around is normaly flown by the pilot but on occasion it can be flown by the aircraft depending on the autopilot set up but even in this case the aircraft doesnt make the decision its the pilots.
You lucky, lucky sod. In my aircraft (not saying what but it is almost 40yrs old) when the Capt. decides to go around, I guard the throttles to make sure he doesn't overtorque the engines. Simultaneously I'm bringing the flaps up to T/O whilst raising the gear and landing lights with my third and fourth hands. The Eng just calls out the Torques and the Nav shouts out the MAP.

It can get a bit busy.....:{

batty
18th Jan 2005, 18:49
We also have to set F15 raise the gear check the GoAround thrust...etc etc...the TOGA is just the start...;)

Bearcat
19th Jan 2005, 07:58
boac....boeing do not guarantee a 737 landing in 40kts x w/v....they have written in legalise that the max demonstrated crosswind is....so in other words if you put it into the grass boeing dont want to know about it.....most companies are 35kt limited.

having flown the lot the best aircraft is sh*tty weather for me is the venerable 737....fantastic roll control.

scroggs
19th Jan 2005, 08:20
The A340-600 has a maximum 'demonstrated' crosswind of 37kts, which is what we use for normal ops. It, like most recent Airbus aircraft, is also equipped with windshear detection which will command (but not carry out) a go-around if windshear is detected on the final approach. The go-around is actioned by placing the throttles in the TOGA position; the aircraft will then climb at V2+10 (or thereabouts) and carry out the MAP automatically.

For SVK; even in this computerised mega-beastie, we still have to operate the gear, flaps and radios manually - and there's no eng or nav monitoring what we do, so it's still pretty tense in bad weather! But, ahhh, I remember it well....;)

PS I'd have thought they'd have realised by now that the lights aren't a high priority at that moment!

BOAC
19th Jan 2005, 08:38
Bearcat boac....boeing do not guarantee a 737 - exactly - hence the apostrophes! The point I was making is that it would be a foolish operator who 'allowed' crosswinds above Boeing's 'demonstrated'.

SVK
19th Jan 2005, 10:55
Scroggs, unfortunately for me I forever dread the call of,

"Co? Isn't the port landing light still extended?"

"Oh bugger! Loadie? Is the landing light still on the wing?"

:}

Ringway Flyer
19th Jan 2005, 20:19
Glad I asked! The driver of the 737, Ryanair EI-CNT, was certainly kept busy over the last couple of miles, enough to get the hen parties on board clucking a lot... But he put it down (a bit firmly!) bang on the numbers, so well done that man. The forecast wind was about 15 degrees off the runway heading, gusting to, I think, about 50 knots.
Seems there's a bit more to do in those big birds than we do in a PA28!

Vlad the Impaler
22nd Jan 2005, 13:26
Very interesting night in 737 land the other day (STN EGSS) landing on 23. wind 310@20 G33. Oh and +25kts windshear @ 150ft........ever seen a 737 land sideways ? scared the c**p out of me and I was only watching..Nearly all put it on the deck first time round, fair play.

meadowbank
25th Jan 2005, 08:12
Ringway Flyer

757 crosswind limits are 40 kts for landing (wet or dry), 40/25 kts for take-off (dry/wet). Pilots certainly earn their salaries when landing in 40 kts crosswind, especially if it's at all gusty.

barry lloyd
27th Jan 2005, 21:42
Ringway Flyer:

I don't know whether you've seen this before, but

www.flightlevel350.com/picwindow.php?cat=198&pic=116[/URL]

will give an example of a crosswind approach which I imagine the crew would rather forget! I gather they got it down on the second attempt.

Chucky_1
27th Jan 2005, 23:41
Edit: Chucky - your question has been moved to a more appropriate forum (http://www.pprune.org/forums/showthread.php?s=&threadid=161092) where I trust you will get an answer.