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Accident report stating demonstrated crosswind limit as general limit

Actual safe landing crosswind is very dependant on the pilot’s recent crosswind experience, and on the smoothness of the runway.

Maoraigh
EGPE, United Kingdom

If there is no demonstrated crosswind speed, there used to be a rule of thumb, possibly historical regulation, to treat it as 0.2 x Vs.

Tailwheel aircraft with reasonable rudder authority can land in surprising crosswinds – it’s the taxi turns in a strong downwind that are problematic! Plan to use taxiways that can handle 270 degree turns.

Oxford (EGTK), United Kingdom

Graham wrote:

Other than that, my crosswind technique is self-taught. Crab with tricycle gear and wing-down with taildraggers.

That is just absurd. Where on earth did you do your lessons?

EGTK Oxford

But this was a take off accident, not a landing. Thus a loss of control on take-off rather than an inability to control drift when landing. Debate.

In Malta I teach all students crosswind landings – sometimes the conditions are quite “sporty”. First we kick straight, then we learn how to slip (wing down). Slipping is not in the syllabus (as airliners normally don’t do it) but the aircraft is capable of slipping thus they need to know. Remember the B767 at Gimli who slipped-in on a high approach after he ran out of fuel… https://en.wikipedia.org/wiki/Gimli_Glider

NeilC
EGPT, LMML

RobertL18C wrote:

Tailwheel aircraft with reasonable rudder authority can land in surprising crosswinds – it’s the taxi turns in a strong downwind that are problematic!

Yes!

NeilC wrote:

Slipping is not in the syllabus (as airliners normally don’t do it) but the aircraft is capable of slipping thus they need to know

I’m glad I didn’t have to endure a fixed syllabus but regardless slipping was and is 100% mandatory to fly the Luscombe in which I learned. That then leads to acquiring crosswind technique without even noticing, it almost takes care of itself, except that you remember to always slip against the wind and verify wind direction when lining up on final – by watching the initial crab angle, something that’s obvious at 75 mph IAS with a strong crosswind. Then set up the slip after the plane tells you in which direction. I later taught myself the ‘kick it out of the crab’ technique when transitioning to my current tricycle gear plane, and it works but feels a bit crude by comparison. Happily the speed is high enough that the crab angle is not too much. I did have some slower tricycle gear experience flying an Ercoupe, with no rudder pedals. In that one you fly it on in the crab and (very importantly) hold the nose wheel up until the main gear side loads straighten the plane on the runway. Super easy if you don’t over think it, with super strong main gear designed for the unusual job. I guess that’s what airliners do.

I remember once circa 2003 going to do some student solo practice in the Luscombe at a local airport on a hill, well known for crosswinds. I’m easily amused. After a while I found myself slipping quite heavily to track the runway centerline on final, with attendant increase in sink rate. After a few more times around I got that figured out with steeper approach, did a few more, then noticed by checking ASOS that the issue had been caused by wind increasing to 20 knots plus gusts directly across the runway. Or half the stall speed (0.5 x Vs). It was a really nice experience, quite a beautiful thing especially since as a student I was so current in the plane at that stage, flying it for under $20/hr fuel cost every time I could get to the airport. Enough rudder authority was available regardless of no factory crosswind demonstration or certified POH – the absence of which seems to be an distinct advantage in relation to the original post!

Last Edited by Silvaire at 14 Aug 04:49

It is fairly widespread in schools/clubs (anywhere where there is a dominant individual “in charge”) to treat the max demo number as a hard limit.

Another factor is that the wind is usually reported from the top of a 30ft pole, so what you see at touchdown is going to be less. However this thread suggests otherwise.

As usual a search for

crosswind

digs out lots of good reading

Administrator
Shoreham EGKA, United Kingdom

The demonstrated crosswind component was the maximum wind that could be found when the test pilot was doing the runs, in front of witnesses.

Usually we fly a contant heading side slip to determine max authority. The rest is geometry.

First we kick straight,

I never teach that, it’s sloppy and results in random landings in high winds. A destinct transition from crab to slip is the way to go. Or touch down crabbing in a tricycle (most fix gear)

Slipping is not in the syllabus (as airliners normally don’t do it) but the aircraft is capable of slipping thus they need to know.

For the LAPL and PPL it is (Excercises 8 for constant track slips, excercise 9 for slipping turns)

Last Edited by mh at 14 Aug 07:33
mh
Aufwind GmbH
EKPB, Germany

JasonC wrote:

That is just absurd. Where on earth did you do your lessons?

Per my post, White Waltham.

Also per my post, we did 2-3 circuits on a crosswind runway. Perhaps I got the hang of it quickly? I certainly don’t remember it being difficult. The principles were obvious to me, and it was just a case of feeling how the aeroplane handled.

I don’t really apply a great deal of conscious thought to the approach. It’s just doing what it is necessary to keep the aeroplane on the approach path. Entering the flare there is a bit of thought about which way the controls will go, and then it happens.

EGLM & EGTN

Peter wrote:

so what you see at touchdown is going to be less

… but in many ways, likely worse.

A steady crosswind, given enough rudder authority, is easy to land with. A gusting one may be more challenging.

When I had only ~6 hrs of tailwheel time, I flew the club’s Cessna 170 to Weiser Airpark (closed this year to have houses built on it :-( ) and Weiser was oriented such it always had a crosswind, and also had T-hangars quite close to one end of the runway which tended to alternately block and funnel the wind – so no crosswind/strong crosswind/no crosswind/strong crosswind as you passed them.

My landing was sufficiently exciting that the people who were sitting on the benches watching the landings actually got up and ran away. I did manage to (just) keep it on the runway, and nothing but my pride was hurt, but it was an instructive experience.

Andreas IOM

My post was about how the test pilot determines demonstrated crosswind components in front of FAA witnesses, not how a normal pilot should attempt to land the aircraft.
It was related to me by the engineer that was present during the certification of the BE35 in 1947, long since deceased.
Anyway, a pilot applying normal crosswind techniques should have no problem up to the demonstrated crosswind component, it is not a limit unless it is in chapter 2 Limitations of the POH.

EBKT
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