Whether the landing gear has a trailing arm has nothing to do with crabbed
crosswind landing ability.

Syd mad an excellent analysis and Bill's comments are interesting and have
merit, too.

Fred Weick came to most all the National Conventions and a lot of regional
ones in his later years.  I **cherished** the moments I spent following him
around as he talked with pilots and owners about their Coupes.  Then there
were special moments when I got to ask questions, too.

One question I asked or a comment I made caused Fred to discuss four-place
planes that could handle crosswind landings for disabled pilots.

I was shocked at Fred's comment.  This comment was made casually but fairly
firmly, as I recall.  I can't corroborate it.  It was out in the plane
parking area and if anyone else was around, I don't recall it.  Perhaps if
I'd aced Engineering Calculus 1 and 2 with vectors 40 years ago instead of
crashing, I could do the calculations.

As I best recall it, this is what Fred said (paraphrased, not word for
word):
>>>>>>>>>>>>>>
The side loads on the plane touching down in the crab are NOT that great.
If you have an egg on a saucer in your lap, it won't go flying.  All the
heavy parts of the plane are near the center and the parts far from the
center of gravity tend to be the light parts, structurally.

Hence, a Cherokee could be safely landed in a crab like an Ercoupe.  Its
landing gear structure is not specifically designed for crabbed landings,
but it really doesn't have to be.

So, a paraplegic pilot needing a 4-place plane could use a Cherokee and just
do crosswind landings like a Coupe, in a crab, nose high, at minimum
touchdown speed.
<<<<<<<<<<<<<<

Back to my voice, now.  Again, that's my memory of his points.

If you go out and break off your Cherokee's landing gear (or another
plane's), you can't say I guaranteed any of this.

Since that conversation, I've paid even closer attention to the instant of
touchdown.  Yes, there is a lateral surge at the moment of touching in a
crab.  But take note, it isn't that strong.

How many of the planes out there have NEVER had a ham-fisted pilot touch
down with a significant side load due to a gust, misalignment or other
clutziness?  How often have you heard of a landing gear being damaged by
side loads from such a landing?

Me, I can't remember EVER having heard of such side load damage.

(Still, with some brittle or especially weak landing gear structures and
materials, I'd intensely avoid any crab to my touchdown.)

I'll grant Syd's point that a low center of gravity is desirable for a
crabbed landing.  If the CG is high, there's the question:  Will the plane
tilt and touch a wing touch before it finishes it's alignment turn or tilt
enough that the wind gets under a wing and it can't recover to upright?
Yet, I suspect that a lot, if not most, individual high wing planes used in
training have tried a side-load touchdown and survived.

If any of you have the math and engineering ability to do a structural
analysis on an aircraft model or two to support or explode this thesis, I'd
be interested in hearing about it.

Ed


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