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WilloW_737

Cross wind landing & auto brake setting ?

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Greetings:

 

When landing in a direct cross wind of around 23 knots (90 degree to landing runway direction), it's often challenging to keep the aircraft centered on the center line immediately after touchdown.

 

Through trial and error, I've discovered that auto brake settings higher than 1 (2-3) provide better lateral control when using the rudder to maintain the center line.  This "appears" obvious as the higher auto brake settings minimize the time that the aircraft is being buffeted by the cross wind.

 

Is this correct procedure ??

 

Are my assumptions correct ??

 

Thank you,   WilloW

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Whatever works for you in the sim. In the real world bean counters only want you using higher autobrake settings for contaminated/short runways. Higher brake settings cost money, on a dry long runway with a crosswind you would be expected to use a lower autobrake setting, idle reverse or max reverse if required.

 

That huge rudder and the required skill should be more than adequate.

 

At the end of the day you are in command, but I don't think an explanation of better lateral control on rollout would cut it if you we're called into the office for tea & biscuits. I think they would send you back to the sim for an assessment :)

 

Btw, all desktop airliner addons are terrible with crosswind and ground handling, combine that with off the shelf rudder pedals and no real feel it becomes pointless comparing it in detail to the real thing.

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Thanks for the reply.

 

I usually use a setting of 1 for the auto brake.  Only recently I accidentally discovered that using higher setting with a strong X-Wind gave better control.

 

As it's not the usual done thing, I'll opt out and go back to using 1 and the pedals!!   Cheers,   WilloW

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Yesterday I was on this flight (in the video)

 

Landed on Rwy 35, Displaced Threshold, Vacated on Delta. B737-800

~1100m Stopping distance.

 

Wasn't in the cockpit, so no idea what autobrake setting was used. I suspect more than 1 ;)

 

http://www.airservicesaustralia.com/aip/pending/dap/SCBAD01-136.pdf

(yes the taxyway designations don't make much sense. P, N, M, C, G, D, F, A1)

 

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(yes the taxyway designations don't make much sense. P, N, M, C, G, D, F, A1)

 

From listening to 774 Melbourne I thought that nothing made sense in Canberra.  :rolleyes:

 

Do you know if VA is repainting the Virgin Blues in the white livery?

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From listening to 774 Melbourne I thought that nothing made sense in Canberra.  :rolleyes:

 

Do you know if VA is repainting the Virgin Blues in the white livery?

 

Yep. Some of the E190's are already in white livery. Even some of the 737-700's that got retired recently got painted in the white livery first, then retired several months later. They seem to be doing the old money saving trick of only repainting them when they are scheduled for a new paint application anyway, so give it 3 years or so lol.

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To close off the topic, I spoke with a 737 pilot fried and he said auto brake is not used for what I mentioned, although it would have an effect on stopping distance. therefore, minimize the time that a cross wind effects an aircraft.  WilloW

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And just so we don't get into sim-isms, Autobrake selection should be covered in company SOP's, so different airlines may have different considerations. Different types of brake (Carbon or steel) different training and/or maintenence programs. Different airports (some have wider/longer runways than others). Some airlines like pilots to utilize automation more than others etc.

 

Bit like southwest and their years of not using autothrottle (and making their 737-700 PFD's look like badly rendered 737-200 cockpits) and in some cases literally covering up the VNAV button so it couldn't be used.

 

One airline wants manual braking used through in crosswinds? don't doubt it. Not sure every airline does the same though. Delta isn't the same as American, isn't the same as Transavia, isn't the same as Virgin Australia, isn't the same as China Southern, or South African etc. They all operate in different environments with their own commercial considerations.

 

Flying into a 60m wide 3500m long runway with Cat III ILS approaches isn't the same as a 30m wide 1800m long runway off a VOR Non-Precision approach, or GNSS RNAV.

 

Using manual braking allows the pilot to control the pressure of each brake, so instead of an even application of left main and right main gear braking system, you can have more braking pressure on the left and/or right side which may assist in steering, basically turning the brakes into a ground steering augmentation system. Considering the pedals also control the rudder at the same time this may be a little difficult to impliment. It also possibly creates more brake-pad wear depending on how much force the pilot applies, whereas an autobrake setting would be potentially more graduated.

 

That said, although there's a bunch of airline-specific guidelines, Boeing put an autobrake system there, but they also put brake pedals on the floor too. It's up to the Captain, in consultation with the airline SOP's and training, to decide what will provide the best outcome, weighing up saftey, passenger comfort, cost, SOP, Airport runway/taxiway configuration, runway surface information, weather etc.

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Hi WilloW,

 

 


When landing in a direct cross wind of around 23 knots (90 degree to landing runway direction), it's often challenging to keep the aircraft centered on the center line immediately after touchdown.

You should checkout the Landing section of the FCTM (Flight Crew Training Manual) included with NGX. In there you will see that if you land fully crabbed, you should expect the aircraft to veer off the centreline at touchdown. Boeing themselves describe this and expect the pilot correct and regain the centreline expeditiously using symmetrical braking and reverse.

 

There are other options for landing in a crosswind, such as de-crabing during the flare or adopting the sideslip method before the flare.

 

They generally have their pros and cons. For example, in strong crosswind and dry conditions, perhaps landing fully crabbed isn't the best option. By the same token at the crosswind limit perhaps the sideslip method won't be sufficient without introducing crab too. Maybe in strong gusty crosswind conditions decrabbing in the flare could perhaps be the least stable. You get the idea I hope.

 

With all that in mind, select the technique most appropriate for the conditions so that the use of autobrake should really depend on the desired stopping distance and turnaround time, taking into account the runway conditions and other factors that affect landing performance.

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There are other options for landing in a crosswind, such as de-crabing during the flare or adopting the sideslip method before the flare.

 

 

Thanks for the replies   I actually favour the de-crab most of the time.  I dislike the side-slip.

 

Saying this, I realize that 23 KN direct crosswind is nearing the maximum.

 

Cheers,   WilloW

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Hi to all,

I'd add another consideration to all the previous answers: differently to real world you've to remember you're alone into the cockpit...no possibility to use toe-brakes (you) and rudders (your fellow in the right seat) to decrab the plane at the same time..so if I had a 30 knots crosswind t that is the crosswind limits on dry rwy for many companies) why  shouldn't I use my autobrake for slowing down while I use pedals as rudder to decrab my plane?

 

Ciao

 

Andrea B.

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You decrab in the flare, it is never a case of PF applys brakes while the other decrabs or vise versa.. And what's all this talk about sideslip? This isn't a Cessna.

 

Andrea, have you ever actually flown a real aircraft?

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My suggestion: Do what the FCTM calls for. If that won't work because of simisms, then modify.

 

Almost no one I fly with does a side-slip on final (one guy in 6 years on the 737).

 

Crabbed landing is very rare, and it's gotta be very windy before I do it, and that's usually on a slick runway.

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Sideslip in a 737 is a late final transition from crab to wind down attitude within in the last few feet before the flare. The result is that the aircraft touches down on one wheel first. This is not that uncommon, many pilots decrab into a sideslip and flare and touchdown wing down.

 

The standard decrab is arguably simpler to perform, but the advantage with sideslip is that that it is easier to control lateral drift during the flare to touchdown.

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The result is that the aircraft touches down on one wheel first. This is not that uncommon, many pilots decrab into a sideslip and flare and touchdown wing down.
I don't know how you can de-crab and not be in a side-slip.

 

3 options, in order of occurence:

 

De-crab in flare

Crabbed

Slide-slip on final (no transition in flare)

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I don't know how you can de-crab and not be in a side-slip.

Well I suppose technically the aircraft is in a sideslip condition when decrabbing. However, for simplicity, I am purely writing in context of Boeing's description of the techniques in the FCTM and their definition of crabbed and sideslip landings.

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