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At the beginning of the movie Mission Impossible: Rogue Nation we can see an A400M taking off.

A400M in the movie

When the engines start, the propellers turn in opposite directions. As I understand it this is not a common configuration but correct for the A400M according to Wikipedia. However, the Wikipedia article also says that the configuration is "down between engines (DBE)" which is opposite from what we see in the movie.

  • Did the movie get it wrong or did they use a special/early version of the A400M which worked differently?
  • I'm also a little confused about the propeller blades, do they have variable pitch?
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  • $\begingroup$ Welcome! Thanks for jumping in with an interesting question. I’m not at all familiar with the A400M, but I’m sure one of these other geniuses will get you sorted out quickly ✌🏼. Hope to hear more from you soon. $\endgroup$ – Aaron Holmes Aug 6 at 1:16
  • $\begingroup$ Tomas I edited my answer based on your comment, it may very well be that the scene simply is played bacwards, I explain the propeller "logic" in my edit. Good thinkin on the reverse scene, didn't think of that myself 😃 $\endgroup$ – Jpe61 Aug 6 at 17:33
  • $\begingroup$ This is two differnt question and they should be asked separately. BTW, a quick basic research shows they have variable pitch. $\endgroup$ – Manu H Aug 6 at 17:50
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I have seen the movie, but it failed to occupy my memory... anyway:

Yes, the A400M propellers are contra rotating, and more specifically DBE as you described. I am not 100% sure, but I'm willing to bet all A400M's ever produced have this configuration.

So if the propellers seem to rotate in the "wrong direction" there are two possible causes:

  • it is an effect caused by camera shutter speed in relation to propeller rpm. This may make the propellers seem to rotate in ever which way, or even stay still, as you can see in this youtube video.
  • the whole scene is cgi, so there actually is no real plane involved. My money is on this...

The propeller blade angle in A400M, as in any larger modern propeller aircraft is adjustable.

This type of propellers, or the governor adjusting the blade angle (pitch) of the propeller to be precise, are typically constructed in such a way, that when the engines are off, there is no oil pressure, and the blades are set in feathered position. So when the engine starts up they will be feathered, and when the engines are shut down, the propellers will adjust to feather. This is basically a safety feature to minimize drag in engine failure situation. To prevent thrust from forming during and immediately after start, the propeller adjustment is set to feather by pilot, this prevents the propeller angle change as oil pressure in the system rises and governor would otherwise start to adjust the blade. As you commented below, it is totally possible the scene is played in reverse, as the blade position would be the same in both shut down and start.

The picture you posted in the question shows propellers in feathered position, so they are not producing thrust. If this is a screen capture from a scene where the plane is taking off, it most definitely is cgi. With propellers feathered, the plane will not be gaining speed, and definitely not taking off.

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    $\begingroup$ Thanks. I have discounted the camera shutter speed option because the propellers can be seen spinning up slowly from 0 rpm. $\endgroup$ – Tomas Andrle Aug 5 at 22:58
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    $\begingroup$ Wait, are they really spinning up? Maybe they are spinning down but it's just played backwards. The feathered position may have been used to keep the camera & crew safe in front of the wing. In any case, Tom Cruise was actually on that plane, a lot of it was real. $\endgroup$ – Tomas Andrle Aug 5 at 23:12
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    $\begingroup$ Surprisingly, they did strap Tom Cruise to the outside of an A400 taking off while the crew were filming on the ground: youtube.com/watch?v=p3XgoDa7RB4 $\endgroup$ – JZYL Aug 6 at 0:08
  • $\begingroup$ Nice find! In that video, at 1:37 (youtu.be/p3XgoDa7RB4?t=97) you can see the propellers spinning, and although they appear to go UBE, you can see the blades are actually bent to go the other way, wich means that's probably a strobe effect. That's consistent with the way they're twisted in the scenes where the aircraft is still. So the actual aircraft used for the filming is DBE. -- But the plastic model is different, and sketch at 0:23 shows all propellers going the same way. -- so it's probably a CGI issue $\endgroup$ – Zak Aug 6 at 15:43
  • $\begingroup$ As a sidenote, mr Cruise hanging outside an actual plane is a (clever, I admin) publicity stunt. Current CGI is so advanced, you just can't tell the difference. It would have been cheaper, safer and faster to fake that, but when you count in the publicity value both for the movie AND mr Cruise, it makes sense. Sort of 😃 $\endgroup$ – Jpe61 Aug 6 at 17:16

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