On a recent trip to the Technikmuseum Sinsheim, I noticed that the back of the Tupolev TU-144 is not symmetric. Please take a look at the picture I took to understand what I mean: (Please don't mind the crane, the Tupolev was getting cleaned that day)

Those parts most likely serve some aerodynamic/stabilizing purpose, but what exactly do they do? Why aren't they the same on both sides?


1 Answer 1


The four parts you're referring to contain the actuation mechanism for the rudder, similar to the wing pods that contain the flap actuation mechanism.

The reason they are not arranged symmetrically is that the rudder has two sections (you can see the 'cut' in the middle in your image)- apparently to provide redundancy and improve safety. So,each section has two actuation mechanisms on the same side, with both of them in opposite sides.

The Concorde had a similar arrangement, albeit with only a single mechanism on either side, as can be seen below.

Concorde rear

By Simon Boddy, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=31619795

  • $\begingroup$ I think the split rudder is more so for the high loads imposed on the control surfaces at higher speed as well as reducing the control authority, see aviation.stackexchange.com/questions/8432/… for a larger discussion on split rudder design. $\endgroup$
    – Ron Beyer
    Jun 6, 2016 at 14:51
  • 1
    $\begingroup$ @RonBeyer That might also be a reason. But the Concorde atleast had a bad habit of losing its rudder rather often. $\endgroup$
    – aeroalias
    Jun 6, 2016 at 15:28
  • 4
    $\begingroup$ @aeroalias I love how that article shrugs off structural failure of a control surface at mach 1.8 as a "non-event." $\endgroup$
    – TomMcW
    Jun 6, 2016 at 16:54
  • $\begingroup$ @TomMcW: Well, said control surface happens to be one that isn't used at all in normal cruise flight, so... $\endgroup$
    – Vikki
    Jan 15, 2021 at 22:44

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