Dave you are creeping me out here. Bella Abzug? Justin -
Well, beauty is in the eye of the beholder..........
And there's an age at which it's like an old dog chasing a car - what the heck do you do with it if you ever catch it?
But more to the point - Joe and Don had (have?) an excellent discussion on V-tail design on the DJ website. Having flown quite a few of both types, the differences are ones of aestehtics but with the caveats:
- For the same tail moment, the volume coefficients (horizontal and vertical) really need to be about the same to make a fair comparison. As Mark noted in a recent post, the euro V-designs tend to be low in the vertical component of these design values. I've noticed this is in several 2M euro designs that I've tried and the problem (for me) is too little vertical volume coefficent (often half of what we'd use in a normal X-tail) and low dihedral angle. These complement each other to make the rudder yaw response rather weak as compared to many US designs. Consequently, my impression is that the 2M ships that are sold as TD in the US are really converted slopers for which a low rudder volume coefficient and EDA isn't all that critical. Since the yaw response to rudder is weak, and the dihedral angle is low, it can be tricky setting up aileron differential and rudder compensation for coordinated turns with these ships for TD purposes (again - for me).
- For a V-tail, you don't need much elevator travel but you need a lot of rudder travel. This seems to be compounded by a weird pitch-yaw coupling on large 'rudder' type movements in a V. That can require differential for the V surfaces as well. My impression is this gets more pronounced if the hinge line is angled significantly.
If you look at the Super-V designs of Mark LeVoe, you'll note that the horizontal and vertical volume coefficient is about in the mid-range for conservative X-tail designs. I think for US TD work, most folks have found the handling of a Super-V to be very good.
Different strokes for different folks. A V is a little more challenging to set up properly but works fine once you get there.
No offense intended to any euro designers with these comments. Just personal observations from a limited number of well-crafted ships.
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