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Mobilae
20th Jun 2019, 09:19
I just transitioned from a larger jet to the 737 and one of the things I noticed is that it is not recommended to perform sideslip only (zero crab) landings in strong crosswinds. According to the FCTM however, the airplane can land using crab only (zero sideslip) up to maximum crosswind.

Being used to landing sideslip only (full decrab during the flare) I'm not sure how to tackle this. Some recommend a partial decrab, but this feels very unnatural to me. A fully crabbed landing on the other hand does not sound very comfortable to me.

So are there any 737 drivers who land it fully crabbed in strong crosswinds? How does that work out? Very curious!

capngrog
20th Jun 2019, 18:02
I didn't realize it was possible to transition from one type to another without undergoing simulator (or real thing) training.

Cheers,
Grog

yoko1
20th Jun 2019, 18:10
I just transitioned from a larger jet to the 737 and one of the things I noticed is that it is not recommended to perform sideslip only (zero crab) landings in strong crosswinds. According to the FCTM however, the airplane can land using crab only (zero sideslip) up to maximum crosswind.

Being used to landing sideslip only (full decrab during the flare) I'm not sure how to tackle this. Some recommend a partial decrab, but this feels very unnatural to me. A fully crabbed landing on the other hand does not sound very comfortable to me.

So are there any 737 drivers who land it fully crabbed in strong crosswinds? How does that work out? Very curious!

Prior to the advent of downward pointing winglets, the standard landing technique taught at my airline was to either 1) start using slideslip around 100-150 feet to give autothrottles time to react, or 2) decrab in the flare. With the new winglets causing clearance issues, we are no longer advised to use method 1 in anything other that light crosswinds. If decrabbing in the flare, it doesn't hurt to carry a few extra knots due to the sudden increase in drag.

Boeing says you can land the 737 in a full crab, but it is not recommended for dry runways due to stress on the gear and tires. When braking actions are less than good, then landing with some crab is less of a problem.

Mobilae
20th Jun 2019, 18:24
I didn't realize it was possible to transition from one type to another without undergoing simulator (or real thing) training.

Cheers,
Grog Sim training only. And yes, of course it included crosswind landings up to maximum. I’ve tried several different methods but I obviously can not comment on how this translates to the actual aircraft. Landing gear/tire stress mentioned by yoko1 above is obviously also not much of a concern in the sim. I’ve tried landing fully crabbed in the actual plane with crosswinds up to 20kts which worked out okay comfort-wise (although it did not feel natural to me). But 30+ crosswinds is perhaps a different story.

Banana Joe
20th Jun 2019, 21:03
Decrab during flare, between 10' and 20' RA, the aircraft can happily take a crab angle of 5 degrees or less in any condition and it is certified to land in a crab according to the guidelines provided in the FCTM. Might not be pretty, but it can be done and it's ok on wet or slippery runways.
The 737 is the only jet I have experience on, but what I can say is that the rudder is incredibly powerful so all it takes is a very smooth application of rudder. And just when you think the amount of rudder you are applying is not enough, it's actually enough!

These are my 2 cents. New on type and still with too little exposure to crosswinds.

ZeBedie
20th Jun 2019, 22:23
Doesn't the 737 main gear have a limited amount of castoring ability?

tomuchwork
20th Jun 2019, 22:27
True.FCTM says such things. Would be the first aircraft in my life that ACTUALLY asks me to do that but I prefer to full decrab it as in most other types(and I have landed easy up to the max demonstrated wind conditions)In some companies you "have to play the game" in the sim and land it as they say. But why not decrab it if there is really no penalty on handling(more an improvement I would say by "decrabbing" it). What the FCTM suggests is one thing that you do not want in an already stressing situation - feeling VERY uncomfortable.

Once properly learned(as most of us know), decrabbing an aircraft is an easy thing.

My advice: Play the "game" as long as you are under training(depending on the linetrainer really, most use common sense and decrab it OF COURSE). Later, if you sit on the left seat there is no issue how you do it as long as it is safe. If you are sitting right discuss the plan during briefing with the skipper - most will be happy.

Switchbait
21st Jun 2019, 00:22
Side slip only and decrab in the flare are two totally different techniques.

To the original poster, just land the B737 in a crosswind the same way you landed your previous type. There is ZERO voodoo to B737 crosswind landings....

john_tullamarine
21st Jun 2019, 05:55
FWIW on the -300, I used just to align with the runway at a suitable height, depending on crosswind (perhaps 200-300ft approaching maximum), sideslip as required to maintain track, pitch up a degree or two to account for the slip, and the old girl would paint herself on every time ....

TheiC
21st Jun 2019, 07:08
Some simulators are known to lack fidelity in strong crosswinds. One that I have used is more or less unflyable above 25 kts across. Years ago one would have written that up and it would have been fixed but standards aren’t what they used to be.

pilotmike
21st Jun 2019, 12:52
To the original poster, just land the B737 in a crosswind the same way you landed your previous type. There is ZERO voodoo to B737 crosswind landings....

NOT good advice to the OP for 737 operation, after they claimed to:Being used to landing sideslip only which by definition means 'wing down'. It is especially poor advice as it goes against the recommendation that the OP kindly referenced. The recommendation is there for very good reasons - engine strike being the most obvious.

Mobilae
21st Jun 2019, 12:57
NOT good advice to the OP for 737 operation, after they claimed to: which by definition means 'wing down'. It is especially poor advice as it goes against the recommendation that the OP kindly referenced. The recommendation is there for very good reasons - engine strike being the most obvious.

Correct. A pod strike would be my main concern. I assume the recommendation is there for that reason.

I've always been very comfortable with heavy crosswind landings, but not being able to fully decrab is a strange thing to me. Guess I'm going to have to make it work using a partial decrab technique.

Switchbait
21st Jun 2019, 13:47
(full decrab during the flare) is what the original poster wrote......

so is he using side slip only, or de crab?? They are two entirely different techniques.

In my reply i assume he was “full decrab during the flare”..... that’s why I said just keep doing what you are doing.

Some folks here here are confusing the terms and techniques....

Switchbait
21st Jun 2019, 13:50
Also, if you flare the airplane at all, you need close to 15 AOB for a pod strike..... Who lands at 15 degrees angle of bank???

Have another read of the Boeing manuals.

sheppey
21st Jun 2019, 13:50
So are there any 737 drivers who land it fully crabbed in strong crosswinds?
Have seen this in the simulator countless times. Usual reason is "because the book says I can." The real reason is these pilots lack the flying ability to touchdown with no drift.

Crosswind landing practice is given low priority during recurrent or type rating simulator training so by the time the pilots get on line they are very apprehensive of crosswinds. They fall into the trap of just planting the aircraft with significant difference between runway heading and actual aircraft heading with a near enough is good enough head in the sand attitude.

There is considerable skill and good timing required to touch down with all drift removed. Some pilots have this natural good judgement while others haven't. The place to hone that skill is in the simulator. Ideally that simulator has proper fidelity. Repeated approaches from 300 feet in strong crosswinds is all that most pilots need to gain proficiency. After all, isn't that why we have simulators?

This scribe has yet to operate a Level D full flight simulator that does not closely replicate the real thing in crosswind take off and landings - otherwise it should not be certified. Where is the training priority in a simulator? A manually flown consistently accurate touch down with drift removed a fraction before touchdown - or - a fully automatic flown ILS with both pilots hands on knees monitoring. I know which one I would admire as a demonstration of pure flying skill..

Goldenrivett
21st Jun 2019, 15:16
So are there any 737 drivers who land it fully crabbed in strong crosswinds?

According to slide 14 of Capt John Cashman's (Boeing's Chief Test Pilot) presentation "Crosswind Guidelines"
http://www.smartcockpit.com/docs/Crosswind_Guidelines.pdf
"* Full crab not recommended for maximum crosswind on Long Beach products"

STBYRUD
21st Jun 2019, 16:25
Yeah, that refers to the DCs and MDs...

Shaman
21st Jun 2019, 19:27
My advice is to ask your new employer what Compamy Policy is on this subject and then stick to it!

All of my employers have said the same thing - remove the drift in the flare by squeezing (NOT kicking) the rudder and apply a little opposite aileron to stop the wing rising.

And, on a jet, never ever use the rudder to pick up a dropped wing - it may be alright on a Cessna 150 but not on a jet. And if you want to know why then ask a training captain at your new employer.

tomuchwork
22nd Jun 2019, 00:13
Side slip only and decrab in the flare are two totally different techniques.

To the original poster, just land the B737 in a crosswind the same way you landed your previous type. There is ZERO voodoo to B737 crosswind landings....

You do not say. Was thinking it is all the same ^^.

Hell. You DO NOT know some (irish:}) operators back here in Europe. They make Voodoo out of their entire 737 OPS(by issuing a ton of FCI's and lot of other crab). All magic(for them) ;) . But I agree - from a (experienced, need to add that nowadays)pilots point of view is is a rather common airliner. Dated(even the NG and MAX), but an rather easy rig. No big deal to handle it during X-winds.

tomuchwork
22nd Jun 2019, 00:25
Also, if you flare the airplane at all, you need close to 15 AOB for a pod strike..... Who lands at 15 degrees angle of bank???

Have another read of the Boeing manuals.




YEP. Some need to do that. Just land the bloody thing as any other airliner. To clarify - that means you are looking with your nose pointing AT the centerliner. Not really something so strange(I hope). Other aircraft, take the CRJ for instance, would have issues with a wing TIP strike, still, you use the same normal technique. Or a Global Express which is even more vulnerable to that(due to the even more swept wings). HOW many tip(trailing edge) strike they have?
Again -on the SIM use whatever your TRE wants you to pass the gig. Most of the time TRE's have a loughable ammount of command experience on type(and in general, other discussion), so DO NOT argue with them, play the game. In the real world, without an TRE grading you on some questionable company procedures do what is safest for you, the passengers, the plane, your license(last but not least).

I have seen some FO's pulling that crap by not fully decrabbing(^^) and I have seen VERY scary landings. Thanks god the folks in the back had no idea, but I was(and sometimes did) ready to interfere that questionable procedure.

sheppey
22nd Jun 2019, 02:34
And, on a jet, never ever use the rudder to pick up a dropped wing - it may be alright on a Cessna 150 but not on a jet.Danger of slight thread drift here. If you are talking about recovery from a wing drop at the point of stall It is not alright on a Cessna or any other aircraft. That is an old wives tale from time immemorial.

exfocx
22nd Jun 2019, 08:37
Have used the "kill the crab in the flare" method from the 146, 320, 733 and the 744 and have NEVER worked anywhere where landing crabbed has been seen as acceptable. Yes, the aircraft are designed to handle it, but it was not viewed as an acceptable landing technique.

Imo the fact that x-wind landings seems to provoke some trepidation is from a lack of exposure prior to airline flying. Where I'm from most pilots have had a reasonable amount of experience from light twins to turbo-props compared to today, with a larger number of pilots coming through cadet schemes then straight onto jets, add the attitude that training is a cost and this is where we end up; pilots feeling knots in their stomachs when faced with x-winds.

It certainly isn't a lack of ability, but training / experience / exposure.

vilas
22nd Jun 2019, 09:14
A fully crabbed landing on the other hand does not sound very comfortable to me.
So are there any 737 drivers who land it fully crabbed in strong crosswinds? How does that work out? Very curious Full crabbed landing is not recommended because the gear is not designed for side stress. In 747 on wet a runway it was recommended to land with crab. On a wet runway the aircraft on touch down with the crab will skid sideways before straightening. This reduces the side load. Interestingly which big aircraft is only side slip zero crab landing is recommended?

Derfred
22nd Jun 2019, 12:18
Interestingly which big aircraft is only side slip zero crab landing is recommended?

That was my question too. Thanks Vilas.

Partial-to-full decrab during the flare with opposite aileron to keep wings level is pretty much the accepted safe technique for jets 737 and larger in my experience. A SMALL amount of wing-down into wind during or after de-crab can be tolerated to prevent drift (depending on geometry - ok on a 737, not so much on a 747).

This is a cross-controlled landing, but it is not a side-slip landing. You are using the aircraft inertia to maintain runway track just prior to touchdown. This is not a sustainable flight path - that is why it happens late in the flare. It is probably more accurately described as a “skid” just prior to touchdown, not a “side-slip”.

sheppey
22nd Jun 2019, 14:53
It is probably more accurately described as a “skid” just prior to touchdown, not a “side-slip”. Agree. That is a good way of describing that late manoeuvre. It takes keen judgement and this is because it requires a few seconds for the applied rudder to swing the nose around to align with runway centreline at the point of touchdown
.A common fault being pilots “Kick” the appropriate rudder pedal at the flare and the wheels hit the runway before the aircraft has time to react. “Kick” is not the appropriate term of course but you get my drift (pun intended..)