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Jarhead wrote:
> "DonMorrisey" <donmorrisey@hotmail.com> wrote in message
> news:1163611333.894101.319580@k70g2000cwa.googlegroups.com...
> | Howdy.
> |
> | I am at the point in my project where I am lining up the landing gear.
> | Based on what I have found from various sources there seems to be many
> | schools of thought asto whether the main gear on a taildragger should
> | toe in or out and how much????
> |
> | Thought I would throw it out here to see what the brain trust has to say
> on
> | this topic. Thanks. Don....
> |
>
> I know you have gotten responses supporting toe out on the main gear
> which is just the opposite of what I was told by a Cessna A&P some years
> ago.
>
> His explanation, as I remember it, is that a slight amount of toe in is
> desirable because as the aiplane started to groundloop, say to the left,
> the left wheel would be more in line with forward motion and the right
> wheel would be causing drag by the sideways scuffing action. Toe out
> would reverse the above which would contribute to the loss of control.
>
> Here is a 1948 Cessna service letter supporting toe in from the factory:
> http://www.cessna120-140.org/Library/serviceletter/SL_Cessna_56.htm
>
I agree with the toe out crowd. Toe in results, in a swing, in the
wheel with the most weight on it, the one on the outboard side of a
turn, getting most of the bite which tends to tighten the turn thereby
creating a certain amount of directional instability. Toe out has a
small "crosswind gear" effect. There, the wheel on the outboard side of
the turn, as it gets the majority of traction due to weight transfer,
tends to steer the airplane out of the turn.
Tony Bengalis talked about this and the number of tail dragger
homebuilts that were sold by their builders due to squirrely behavior
because the owner put toe in.
In the Cessna SL they are concerned with tire wear and their goal is to
get neutral toe in while rolling to maximize tire life. I think that
they calculate that the rolling drag pulling back on the tires tends to
twist them in a toe out direction normally and therefore a slight amount
of toe in is set which is removed as the airplane rolls so the wheels
are more or less neutral.
Although the goal generally seems to be to achieve neutral wheel
alignment, I think a small amount of toe out is desirable on more short
coupled aircraft that need all the stabilizing help they can get.
John K
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Re: Toe in or toe out?? For Taildraggers
