3
$\begingroup$

If they do then what aircraft are they installed in? This stabilizer is not a T-tail shaped stabilizer.

enter image description here

As you can see there are 2 v-shaped vertical stabilizers with a horizontal stabilizer hanging on the each of the vertical stabilizers. So different from a V tailed. And what advantages would this design have over a t-tail for example?

$\endgroup$
  • $\begingroup$ Are you asking about a v-tail, or is your model different? $\endgroup$ – Pondlife Sep 17 '15 at 0:58
  • $\begingroup$ @Pondlife Different look at the 2 vertical stabilzers and you will see that each stabilizer has a horizontal stabilizer hanging off the end of it. $\endgroup$ – Ethan Sep 17 '15 at 0:59
  • 5
    $\begingroup$ Paper airplanes and real ones can't be compared easily, they work at different aerodynamic scales with different Reynolds numbers (though new flying devices come close and even further in downscaling), and mostly in turbulent air. If you can't find an implementation of this empennage mixing V and T tails, then it's likley because more optimized ones exist for actual airplanes. If you're interested in knowing why, then why not move the question in this direction? $\endgroup$ – mins Sep 17 '15 at 11:19
  • 4
    $\begingroup$ Doesn't seem OT to me - it is about aircraft. It might make some scratch their heads and ask "why", but the kid's showing some outside the box thinking, and that's what got man flying in the first place. $\endgroup$ – FreeMan Sep 17 '15 at 12:23
  • 2
    $\begingroup$ It looks like a variation of a Pelikan, which has never actually been flown. $\endgroup$ – fooot Sep 17 '15 at 14:27
8
$\begingroup$

I don't know if such a structure actually exists, but I find it difficult to see why anybody would build one.

Firstly, placing the horizontal stabilisers at the top of two separate tail fins will require that each fin is strengthened to support the extra weight and the aerodynamic loads,

Secondly, there will probably be any number of aerodynamic issues around the joints between the components, each of which will be doubled.

Thirdly, in a real aeroplane you will have introduced substantial complexity into the control systems that have to manage all of this.

There may be other issues, but I see very little benefit aerodynamically or structurally to such a layout.

A conventional V-tail involves some control complexity, but does away with the weight of the vertical stabiliser. A T-tail retains the vertical stabiliser, but avoids control complexity, aerodynamic issues that may occur close to the engines, and can use the extra length to improve the leverage available to the horizontal stabiliser.

All that said, aircraft design is about compromise and utility. There may exist some powerful reason for adopting a sub-optimal layout to fulfil some specific purpose. You can see such an example in the design of the AN-225 Mriya which was originally built to transport the Soviet Buran spacecraft. The vertical stabilisers were moved to the ends of the horizontal stabilisers to keep the clear of the wake from the spacecraft riding piggy back. The 747 used to transport the US Space Shuttle had a similar modification, but retained the original vertical stabiliser.

Soviet Buran spacecraft during transport:

enter image description here

US Space Shuttle Atlantis during transport (image source: Wikipedia/NASA):

enter image description here

$\endgroup$
  • $\begingroup$ I wouldn't say that it has very little benefit because I put this type of tail on a paper airplane and it flew just fine and wasn't difficult to build it either. $\endgroup$ – Ethan Sep 17 '15 at 8:36
  • 1
    $\begingroup$ Interesting paper on tail design, by Mohammad Sadraey, Daniel Webster College. Includes rationale to select a design over the other. $\endgroup$ – mins Sep 17 '15 at 13:18
  • 9
    $\begingroup$ I'm not sure the application of anything to a paper airplane is going to show benefits or downsides. There's just not enough in common with an actual aircraft. $\endgroup$ – egid Sep 17 '15 at 15:06
  • 4
    $\begingroup$ I'd also add that for a full size plane this design would lead to relatively high bending stresses at the top of the fin, due to the abrupt change from horizontal to near vertical. This would be worse when the tail is generating a high pitching moment. (I agree with all points in the answer by the way, this is just another bit of detail for Ethan to consider looking into.) $\endgroup$ – Andy Sep 17 '15 at 16:42
1
$\begingroup$

As far as I know, and my searching for weird/unusual/concept aircraft has yet to reveal this type of design in use or proposed... even if it appears familiar or should have been proposed. The kicker here is the V-component. You can get tandem rudders, in various configurations, inverted V, V, split Vs, or V and elevators. The design here is V, split, with a T-top

[Hopefully someone that can explain the aerodynamics better will come along] Generally, this type of design would be considered redundant and too much extra weight for no general gain. A V type configuration will generally replace both the Rudder and Elevator into a single component. To then re-add an horizontal stabilizer would be redundant. Additionally you'd have to have more support structure in the V to be able to support the horizontal stabilizer and the forces it'd experience.

From the image, it looks like a paper airplane, and if that type of design works, it's probably more due to the addition of more lifting surfaces that give aid towards better stability.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.