Crosswind approaches - transatlantic differences

[Bear Cub]

Firstly, thanks for all the responses to my "single engine twins" thread - that has just slid out of the "past 5 days" catalogue.

However, following my research on the differences of "standards" (for want of a much better word)- it seems that there is another difference in teaching.....crosswind approaches.

I get the impression that the majority of FAA instructors are saying "fly one wing low, maintain runway heading"....whereas CAA instructors told me "wings level - track runway centreline".

I really am not trying to start a transatlantic battle as to who is right - but I would, again, be grateful for your opinions on which is the better method...and (of course) why?

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[Mr B. Tupp]

As an instructor teaching at a small airfield in Scotland that suffers from some every bad crosswinds I must say that I prefer the "crab" technique. That is wings level, maintain centreline. The amount of drag that wing down creates requires a lot of power to maintain speed add to this the cross controls and the usual amount of turbulence that my airfield suffers in a northerly crosswind and your average student melts in his (or her) seat. Much better to "kick off the drift in the flare and then use wing down if the flare is a little too high.

[rolling circle]

Both methods work equally well. The reason for the difference reflects the different objectives between the bulk of FAA training and the bulk of CAA training.

NOTE: This is not intended to suggest either type of training is better than the other, that is a separate argument!!

In the main, FAA training is geared towards putting the trainee into a light aircraft and the techniques are taught accordingly. However, much UK training is geared towards a professional licence and flying the big jets. In the latter case, if you use the wing-down technique, you stand a good chance of leaving some or all of the engine pods at the touchdown point.

Horses for courses.

[Wee Weasley Welshman]

Crab man myself.

WWW

[Oleo]

Combination method myself. Slipping is uncomfortable for your passengers, but I like to get into the slip about 2/3 of the way down finals: this helps me to "get in the groove" and get the feel of the plane.

Those who can keep it in a crab and kick it straight all in the flare are much more clever than me. Plus it gives you a better gauge on whether or not you are going to run out of rudder, and whether perhaps another runway/airport might be a better choice.

Being an old dragon, I make my students slip the majority of the way down final cos it really sharpens their skills for this manoevre (spell?) and correspondingly increases their confidence.

I didn't get really comfortable with X-wind landings till I did my instructors rating and was made to go out and hammer the circuit in a very stiff wind. Very character forming!

[dragchute]

Bear Cub

The wing down method develops control particularly during the round-out and touch-down. Additionally the student will have a better opportunity to practice such control if the slip is established from fifty or a hundred feet above the threshold. Some aircraft however may have limitations on sideslips.

The wing level method requires accurate rudder input before touch-down and may present a judgement problem with early students particularly in gusty conditions or if floating is a factor.

I don't quite subscribe to the belief of 'rolling circle' on CAA/FAA reasoning. Any experienced pilot heading towards a commercial career should be able to competently handle either technique!

As an aside, many Aeroplane Flight Manuals recommend that flaps be left retracted for cross-wind landings. Bearing in mind the lack of head-wind component this technique degrades obstacle clearance and extends the landing distance. Personally I prefer full flaps. What are the thoughts out there?

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dragchute
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[Bear Cub]

Thanks for those comments....now how about we add the two threads together..

Consider that we are left downwind for a westerly facing runway, at Mr B. Tupp's small Scottish airfield (Dundee?) during a period of high, gusty, crosswinds from the North - his scenario, not mine.

Let us now assume that we are flying towards this runway in a low performace twin engine aircraft - with the left engine feathered.

No suitable diversions available - we have to land.

What configuration are we going to be in - at what points in the circuit - and when do we put the gear down?

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[foxmoth]

I don't think this is really a Transatlantic difference, I know plenty of instructors in the UK who use wing down - though they are probably mostly 'old school'. I think most pilots with experience use a bit of a combined technique anyway (but don't normaly teach it that way. I tend to show both and see which the student is happiest with - unless it is tailwheel, when I would definitely go with wing down.
As far as the S.E. twin, short runway etc. goes - that is when having plenty of diversion fuel comes in handy - go somewhere else! (if you are really STUCK with it THEN use crab) :) :)

[chicken6]

I prefer the crab technique until over the threshold, then straight with rudder, use aileron to compensate for drift.

I learned at an airport which was set at 30deg to the prevailing wind, and we were taught this basically from the word go. Now I teach at a different airport where we have two runways, and I still teach crab to those doing crosswind circuits. FWIW, we have the luxury of picking the days when we take students circuiting and can frequently (enough) fly in <5kts. This means that we don't need to teach them crosswind landings in strong crosswinds until around the steep turns/FLWOP level. Definitely before X-C though.

Some students do have trouble visualising what's meant to happen in the flare, and with these I show them the slip from the start of final so they know what it's meant to look like when you flare. Then I gradually decrease the distance they are flying out of balance setting themselves up for a wing drop until they only need to do it in the flare or just before. Thanks for that one Azzie.

Also, this means you need pretty good aileron effectiveness in the flare to combat drift, =>higher airspeed needed=> *no* flap.

My two cents worth.

As for the twin - get way too high on final and glide it in! Sure as hell won't bounce, and no dragging the U/C sideways. Better have those 8-foot oleos well pumped up though!

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Confident, cocky, lazy, dead.

[BlueLine]

I use both methods depending upon the aircraft. High wing is suited to wing down and low wing is suited to crab. Don't think that has much to do with either side of the Atlantic.

[Oh OK]

Depends on conditions - gusty nasty stuff and I teach crab, converting to wing down at about 50 feet - I tried teaching wing down all the way a few times in these conditions - but the student usually goes gaagaa due to cross controls and weird feelings of the slip. However, in a rare steady smooth crosswind I'll teach wing down - which seems to help later on with their last 50 feet during the more usual gusty stuff.

I don't think there is a right or wrong - some seem to like / cope with one or another technique - but I do think that its best to know how to do, and the limitations / benefits of each method.

As an aside, I'd be keen to compile a list of 'pithy'confidence-building phrases used by other instructors during the last few feet, when things get interesting!!!

[Bear Cub]

Pithy confidence builders?

You could try reciting the Lords prayer over the intercom.

Psalm...is it 18?..."The Lords my shepherd...".

Just a thought.

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[Luftwaffle]

In Canada the authorities want us to teach wing down, because the student then holds the same inputs all the way to the ground, with no abrupt changes.

[Bear Cub]

Luftwaffe - as I said, how would you combine this with an assymetric approach when the into wind engine has failed and people want 5 degrees bank towards the live engine?

If you are going in to agree with chicken 6 and glide it in....let's add the snag of having to do an instrument approach and maintain a glide slope. That will require power on the live engine.



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[dragchute]

Bear Cub
In the asymmetric/crosswind situation, one would be simply 'tracking' during the instrument phase of the approach and laying off drift to compensate just like always.

However, on short finals and visual - say at ten to fifty feet above the threshold - power on the live engine would be reduced to idle and the appropriate wing banked towards the crosswind regardless of which engine failed.
Without power the asymmetric situation no longer exists.

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dragchute
email: [email protected]

[Luftwaffle]

Bear Cub, my comments were with reference to initial instruction in singles, not multi-engine instrument work.

In twins here, the 5-degree bank is permitted but not demanded. If you hold your heading, maintain a reasonable airspeed, and maintain your altitude or glide slope, it's acknowledged that there's more than one way to skin that cat.

[Bear Cub]

Ooooh. Bad phrase.

What did the cat do wrong?

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Hunting is bad!!
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[V2+10]

Hi fellow aviators!

Some realy good issues have been pointed out in this topic and personally found that proberbly 9/10 PPL student couldnt handle the wing down method in gusty conditions.
I use the wing down method to give the student an idea for how much rudder is required to keep the A/C on RWY HDG, with myself having control of the ailerons and elevator and the student on the rudder.

The idea is for apreiciation(?) to be felt on how much rudder pressure is required, plus the increase in pressure reqired when the throttle is closed and the flare is commenced, due to the loss of rudder authority and not to release the pressures when the A/C touches down.

Both methods have there advantages irespective of which side of the pond you are flying at.

Regs.

[rolling circle]

All very interesting, but my original point still stands. Wing down technique may be OK for puddle jumpers, try it in my jet and I'll break your wrists!

[A and C]

I have found the "crab" is picked up a lot quicker than the wing down iv used both on aircraft up to F27 size and have found the crab better and as RS says there is not much room under them CFM ,s.

[Dan Winterland]

I think it is a Transatlantic difference. I Fly light aircraft on both sides of the pond, and on one check flight at a school in Florida, the @rse sitting next to me proffered the opinion that I had obviously never flown taildraggers as I opted to land the C150 using the crab method as oposed to the wing down. (He then let me know that he had 50 hours on Cubs - I couldn't be bothered to explain I had over a thousand hours instructing on Chipmunks).

The way I seee it is that the wing down method allows for a bit more x-wind (perhaps - depending on aircraft type) but means you have to fly the aircraft onto the ground to a certain extent.

I like the crab method, because that is what I was tought in the RAF - the preferred method (unless you fly the Herc I gather). My first aircraft had a swept wing and underwing stores only three feet off the ground. Crab method only!

[Victor B1a]

"Horses For Courses"
Dan,
We used to get the odd lift on Chocolate Bombers from Leuchers to Marham in the seventies and the prefered crosswind trick was indeed to drop the wing into the breeze.
We however "crabbed" the tankers in true RAF tradition.
I'm not an instructor but having watched the Herc jocks strut their stuff,and given that we were using big long runways as opposed to wee bits of semi-level turf,the choice may have something to do with ground clearance of all the bits hanging off.

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[quote]Watch well lest the ground riseth up and smiteth thee.[quote]

[Dan Winterland]

Sounds like the same tanker! Of course, the big disadvantage with kicking off the drift in a swept wing jet is that you need a lot of aileron to counter the secondary roll. My current steed (the other tanker with 4 Conways and a T tail) needs full aileron/differential spoiler to counter the roll at it's max X wind limit of 28 Knts.

Still prefer the crab method though. In something like a Cessena, you are sideslipping down the approach, and it just don't feel right.

[300hrWannaB]

Too much sideslipping and it becomes a bad habit used on straight approaches for height loss. Joe P is happier seeing things like he saw from his recent holiday to Majorca in that very nice 737.
As for this tosh about not having to kick of drift until the flare...with a crab approach you can physically see where the wind is from, and how much. No sums. It then becomes more natural.

bounce bounce bounce http://www.pprune.org/ubb/NonCGI/redface.gif