I would guess it is aerodynamically preferable to have the vertical tail out of the boundary layer of the fuselage as much as possible.
Maoraigh wrote:
When the rear engine jets with high tails came in, I suspect the hightail singles were a fashion choice.
Just like when swept tails on jets came in, swept tails on GA aircraft started appearing, despite being worse performing in every important respect when used on a SEP.
T-tails are popular on gliders though, but I suspect this has more to do with glider tails being so low to the ground (the horizontal surface on a low tail glider will be often only about a foot off the ground) and so a T-tail will be much less likely damaged in an off-airport landing.
Probably, all modern gliders have T-tails for the following reasons:
1. Ground clearance for off-airport (= field) landings.
2. Less interference drag as the upper surface is continuous.
3. Slightly better rudder authority (“elevator” works like a winglet).
(4. Easier assembly of the gilder out of the trailer?)
The only exception I am aware of as far as modern gliders are concerned applies for gliders specifically designed for aerobatics: the mass of an elevator at the top of the rudder leads to more torque load on the fuselage tube. Thus, the T-tail is not used for structural reasons.
T tails in piston GA were done AFAIK to look good on the ramp.
Mechanically they must be less strong, and more troublesome, because you have to reinforce the VS structure from base to halfway up, and have an extra joint in the control linkage.
The MCR01 Ban-Bi and Spacek SD1 would be examples of modern, diminutive designs that are built for efficiency and have T-tails.
The T tail on my plane is to keep it out of the water. It’s position has zero effect on handling. Other types have T tails for other reasons, and there are handling differences in some. Pilots new to a T tail plane should either get some type training, or approach with caution for the first few circuits.
HK-36R wrote:
(4. Easier assembly of the gilder out of the trailer?)
That has actually always been a big pro for T-Tails in gliders: With a T-Tail the horizontal stabilizer is one part that can be detached. For non-T-Tails it is two parts – so double the options to mount it wrongly, forget a splint, etc.
(4. Easier assembly of the gilder out of the trailer?)
That has actually always been a big pro for T-Tails in gliders: With a T-Tail the horizontal stabilizer is one part that can be detached. For non-T-Tails it is two parts – so double the options to mount it wrongly, forget a splint, etc.
Not really sure, if this is really true. Even for non T-tail gliders, the elevator is generally one piece: Libelle, Ka6, Ka8, Fox, Swift, …
I heard it said once (sounds plausible, but really don’t know) that the T tail in something like an Arrow and others helps to reduce some of the aircraft internal noise because the T tail is lifted above most of the turbulent prop wash into smoother air. So less surface to collect the ‘drone/drumming’ of air spiralling around the fuselage.
However, one of the drawbacks of the T-tail is the possibility of getting into a deep stall with the tail shielded by the wing
This may be relevant on a swept wing design, not sure so applicable to straight wing GA.
A theoretical benefit of a T-tail in GA is there is less risk of rudder blanking in a spin, but I doubt this is why Piper introduced T-tails in the Lance and Arrow.
