Winglets are used to reduce induced drag on the main wings of an aircraft as per explanations on wikipedia. Since they are very effective I was wondering why they are not installed also on horizontal stabilizers. For sure there must be some sort of induced drag being generated on horizontal stabilizers too as they are cutting through the air just as the main wings do. So why aren't there any sort of "minified" winglets available as an aftermarket installation (or, at least, I haven't ever seen some myself)?

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    $\begingroup$ Induced drag is caused by the pressure difference over and under the wing meeting at the tip generating a vortex, not by "cutting through the air" (that's straight up drag, not the 'induced' kind) $\endgroup$
    – falstro
    Apr 15, 2014 at 10:01
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    $\begingroup$ Or in other words, induced drag is induced by producing lift. $\endgroup$
    – Jan Hudec
    Apr 15, 2014 at 19:34

4 Answers 4


Horizontal stabilizers don't generate as much pressure difference as the wings. Generally the stab deflections are very small in flight, and there's so much other drag during landing -- when the stab gets the most use -- that wing vortices from the tail are probably the least of your problems. Stabilizer winglets on their own, when there's no pressure difference, would simply result in drag, whereas the main wing winglets are constantly effective while flying.

Furthermore, the weight and trouble of adding little winglets to the horizontal stabilizers with larger actuators and hinges, for example, would probably outweigh the very slight aerodynamic benefit. I could also imagine that since the airflow over latter part of the wing is complex and varied, find a good design solution would be difficult.

As @Federico points out, the DA42 has them, but that's a composite airframe rather than the metal construction you see in most Cessnas, for instance, where you have to be more conservative in construction.


Short answer: In all cases these are not winglets, but fins.

Winglets are worse than an equal span extension and are only used if span should not increase:

  • for limiting the wing's root bending moment, or
  • for size limitations

Putting them on the tail surface would not help to limit the wingspan: The horizontal tail can easily grow and still be much smaller than the wing. There is no single case where winglets on a horizontal tail would have made sense.

What you see and might interpret as winglets are actually additional fins. They stay in the general area of the vertical tail, so they do not increase the sideslip-induced rolling moment, and they do not increase aircraft height. But they help to improve lateral stability, which had been worsened by a configuration change. Example pictured below: The Beech 1900, a derivative of the Beech Super King Air. The fins below the fuselage could not grow any bigger without risking ground contact during rotation, and the small stability deficit did not justify the development of a new tail section. So the fins were added where they would cause the least amount of trouble. Obviously, aesthetics were not considered.

Beechcraft 1900 commuter

Note the small planes at the bottom of the vertical tail: The same trick was used to avoid increasing the size of the horizontal tail. It could be argued that the horizontal tail of the Beech 1900 is a double decker.

And no, those horizontal fins are not "fuselage winglets".

So-called "winglets" on the tail of the DA42

That is also the reason why the "winglets" are so much bigger on the MPP version of the DA42: They offset the destabilizing effect of the camera pod. The canted tips of the original DA42 are working like an anhedral and create a compensating positive rolling moment for the vertical tail's negative sideslip-induced rolling moment. Ideally, the whole horizontal tail would have anhedral, but it was preferred to keep the elevator hinge line straight.

  • $\begingroup$ The 1900D's tail region looks like something designed in Kerbal Space Program. $\endgroup$
    – Vikki
    Oct 7, 2019 at 4:01

So why aren't there any sort of "minified" winglets available as an aftermarket installation?

Actually the DA42 has them enter image description here

and in the MPP version they are even more pronounced enter image description here

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    $\begingroup$ i'm not sure these are the pressure difference purpose like classic winglets. IMHO just from appearance it looks like the DA42 has a very short rudder, so these might be for stability purposes :) $\endgroup$ Apr 15, 2014 at 11:16
  • $\begingroup$ @Manfred actually pilots I have spoken to report that these worsen the stability, not improve it. $\endgroup$
    – Federico
    Apr 15, 2014 at 11:17
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    $\begingroup$ Look at the camera platform of the DA42 MPP: This decreases lateral stability, and the so-called "winglets" are simply additional fins to bring lateral stability back to normal. These are not winglets at all, but fins $\endgroup$ Jan 17, 2015 at 11:33
  • $\begingroup$ @PeterKämpf call them the way you want, the pilots report a loss, not a gain, of stability with them installed (and no camera platform) $\endgroup$
    – Federico
    Jan 17, 2015 at 22:14
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    $\begingroup$ @rbp: The strakes are for stability at high sideslip angles. At small sideslip the vertical tail will do fine all by itself, but it will run into a stall around 15° of beta, and then the strakes help out. But this is all besides the point. The stability of the whole configuration is finely balanced, and then that camera pod is added in front. So now something must be added in the back to regain lateral stability, and that is what the fins are for. They were never intended as winglets, even if they might help the horizontal tail a bit. $\endgroup$ Jan 18, 2015 at 19:44

The induced drag from wingtip vortexes is mostly on lift generating surfaces, horizontal stabilizers don't generate that much lift.

That said there is a twintail design with double vertical stabilizer at the ends of the horizontal one; but that is not for reducing vortexes but for improving rudder response.


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