One of Eric's points earlier was the added drag most full castering tailwheels would present. On his ASH26E, the steerable tailwheel is limited in it's steering range to about 30 degrees to each side. Thus the tailwheel fairing can have a reasonably small opening and the extended part of the tailwheel presents minimal drag.

In order to fully caster, the tailwheel structure would either have to extend out far enough, or the boom would have to be fat to accomodate complete rotation.

Course the tailwheel could be retractable . . . more complex and expensive. Cost/ benefit?

bumper