RE: LT-40 Century Model
The three-point stance of the tricycle gear is less stable than a tail-dragger configuration; primarily because the three points of contact on the former are much closer together than the latter.
As a practical example, let's say you're taxiing with (or against) the wind, and need to turn around. As soon as you reach just beyond crosswind, the model is going to try to tip over; because the short distance between the nosewheel and the main wheel opposite the wind is not great enough to overcome the wind's attempt to push the model over.
The distance between the three points is much greater on the tail-dragger, and it therefore resists the wind's efforts better. Of course, this is also the reason why a tail-dragger is a bit tricky on take-off; the longer fulcrum of the steering element (the tailwheel) means that it is MUCH more effective than a shorter-coupled nose wheel; and every error or correction is multiplied.
Hope I 'splained it well enough. But if I didn't, trust me; the phenomenon exists.
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