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When the emergency doors over the wings are opened do the wings automatically lower themselves, to allow passengers to slide and reach the ground? Or does the pilot have to do it from the cockpit?

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    $\begingroup$ I initially read "lowering of gear" and I was actually looking for an answer. then I realized thet you are asking about lowering the wings!? Where have you seen/heard of such a thing? $\endgroup$ – Federico Sep 1 '15 at 11:01
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    $\begingroup$ ah, lowering "the wings" gives quite a different mental image than "lowering the flaps" $\endgroup$ – Federico Sep 1 '15 at 11:05
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    $\begingroup$ Although this seems to be a strange question for those of us with aviation knowledge, I don't agree with the close votes - it's still an on-topic, valid (if slightly obvious to most of us) question, which is clear to understand and also has a single clear answer. Therefore it does, I believe, still fit as an Aviation.SE question. $\endgroup$ – Jon Story Sep 1 '15 at 13:07
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    $\begingroup$ I have to second Jon Story, if the OP meant wings we should not change it only because it makes no sense to us. $\endgroup$ – Federico Sep 1 '15 at 17:31
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    $\begingroup$ The question makes perfect sense. Sometimes 'no' is the correct answer. In fact the 'best' answer would probably be to say neither, then point out that his impression may have come from either flaps (eg most aircraft would typically lower flaps before crash landing) or a gear up landing. Answer the question better rather than changing the question to match the answer you'd like to give $\endgroup$ – Jon Story Sep 1 '15 at 17:36
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Wings are static.

The wings do not move in response to emergency door opening. There is no requirement regarding position of flaps, in most cases involving an emergency evacuation after landing, flaps are likely to be extended, but I don't think this is guaranteed.

Evacuation assistance

On commercial transport aircraft, there are marked routes on the wing for passengers and, if the exit point is more than 6ft from the ground, there are self-inflating slides that allow passengers to reach the ground.

enter image description here
Image from video by "Airline_Alex"


Evacuation on water

The inflated slides also work as life-rafts in the event that the aircraft comes to rest in water and has to be evacuated. Generally this applies only to slides at main exits, over-wing exits have slides that are not designed to be used in this way.

enter image description here US 1549


Regulations

The regulations in the USA say

Each passenger-carrying landplane emergency exit (other than over-the-wing) that is more that 6 feet from the ground with the airplane on the ground and the landing gear extended must have an approved means to assist the occupants in descending to the ground.

The manufacturer must demonstrate that they can evacuate all passengers and crew to the ground within 90 seconds using only half the emergency exits.

This applies to aircraft capable of carrying more than 44 passengers.


Variations in arrangements by aircraft

Not all aircraft need overwing exits and slides. Here are some B757 variants

enter image description here enter image description here enter image description here
From CRJ Resets

Boeing 737

As commenters have noted, the 737 does not have self-inflating slides for its over-wing exits.

enter image description here
Pessini

The 737 system does not always work very well

Passengers climbed onto both wings, which were slippery due to the rain, but were able to see the markings indicating the direction of movement. It was difficult to see the ground in the dark and some passengers were not aware that they should slide down the flap surfaces. Others expected to find an escape slide. On the left wing, some passengers slid down onto the ground and assisted others. On the right wing, fewer people slid down to the ground, while others re‑entered the cabin and exited it using door escape slides when it was apparent that there were no visible signs of danger.

- from AAIB report

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    $\begingroup$ Do all commercial airlines have over-wing slides? $\endgroup$ – Firee Sep 1 '15 at 14:16
  • $\begingroup$ @Firee I believe that every exit door will have a slide attached so that if the plane makes an emergency landing, passengers & crew will be able to safely make it to the ground - it can be a pretty significant drop. $\endgroup$ – FreeMan Sep 1 '15 at 14:40
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    $\begingroup$ @Firee It is standard practice to shut off the engines after an emergency landing (assuming they're still running after everything stops moving). Generally the cabin crew will not begin the evacuation until that has been accomplished as having your passengers survive an emergency landing only to be swallowed up or blown away by the engines makes for really bad press. $\endgroup$ – voretaq7 Sep 1 '15 at 16:36
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    $\begingroup$ @Firee jetblast (and passengers getting sucked in) is an issue with the other exits as well. that's why they get shut down. $\endgroup$ – ratchet freak Sep 1 '15 at 18:24
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    $\begingroup$ B737 does not have slides for its overwing exits and passengers are expected to slide down the flaps, which is I suppose the reason for the question. $\endgroup$ – Jan Hudec Sep 1 '15 at 19:13
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There are no transport aircraft where the wings would be movable.

However if you meant flaps, the question would make sense.

In most aircraft the overwing exits are equipped with inflatable slides that inflate aft over the wing trailing edge (see the image in the other answer). However in some aircraft it is indeed intended that the escaping persons will slide down the flaps, most notably on Boeing 737:

Boeing 737-800 evacuation procedures
(copied from this answer, the original source seems unfortunately dead)

No, the flaps don't move automatically. The pilots have to extend them. Worse, the flaps require power to move and they move rather slowly, so they may not extend all the way due to lack of time or failure of the necessary systems.

I've seen some incident report involving evacuation where it was mentioned that the flaps were not extended all the way down due to lack of time, but I don't remember enough details to find the reference now.

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  • $\begingroup$ The dead source is from here where they have a 737-700/-800 flight safety card currently for sale. $\endgroup$ – FreeMan Sep 1 '15 at 20:25

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