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Cessna 140's vertical rudder axis Cessna 152's leaned rudder axis Concorde's vertical rudder axis Tupelov Tu-144's vertical rudder axis Boeing B747's leaned rudder axis

I was thinking that canted rudder hinges are used for modern aircraft while the vertical ones are used for old slow airplanes. But it seems that I was wrong since the SST Tupelov Tu-144 and the Concorde also have that vertical (or almost vertical) rotational rudder axis. Then my question is, what is the advantage and this advantage of such a rudder? Which one is better?

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The vertical tail of the A380 in the last photo is swept back. Surface sweep is used for high subsonic wings and tail surfaces, to postpone the effects pf compressibility when approaching the speed of sound. And when the vertical tail is swept back, the rudder hinge will be at an angle as well: the rudder chord will be a relatively constant percentage of the vertical tail chord, for aerodynamic and structural reasons.

The two photos of supersonic aeroplanes show vertical tails that are not swept back - they cruise faster than the speed of sound and do not have to postpone any compressibility effect, they fly right through it. No reason to sweep anything back here.

And the photo of the little Cessna with swept back vertical tail: it only looks as if it is trying to postpone any compressibility effects. Of course, it does so by flying way slower than the speed of sound, and the vertical tail is only swept back because it looks super fast.

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    $\begingroup$ Sweep helps to widen the beta range in which the vertical works well. It is not only for looks. $\endgroup$ Oct 3, 2019 at 1:46
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    $\begingroup$ Having flown a number of straight tail and swept tail single engine Cessnas, I can tell you the effect is not detectable on a GA airplane. Cessna went to swept tails in the 60s purely for styling reasons. $\endgroup$
    – John K
    Oct 3, 2019 at 2:59
  • $\begingroup$ @PeterKämpf what does widening the beta range mean in this case? I cannot find info about "beta" except for propellers $\endgroup$
    – user21228
    Jul 31, 2022 at 11:44
  • $\begingroup$ @qqjkztd Beta here means sideslip angle. Using beta for both airflow direction and propeller pitch is rather silly, given how many greek letters are available ... $\endgroup$ Jul 31, 2022 at 17:45
  • $\begingroup$ @PeterKämpf thanks, following this logic, gamma should be for roll and delta for thrust, which could explain why delta is used for deltaV. But it seems phi is for roll, sigh $\endgroup$
    – user21228
    Aug 10, 2022 at 19:49

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