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I was flying on an A320 (equipped with sharklets) the other day, and I found these hooks on the wing's surface:

Note that the single hooked attachment is outside the wing's "DO NOT WALK OUTSIDE THIS AREA" line. What are these hooks used for? Why is the single hooked attachment outside the "safe" walking area line?

shortstheory
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3 Answers3

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In the event of a water evacuation, there is a line associated with each overwing exit that is extended, and clips to that yellow bracket, as a guide to get everyone out on the wing.

From Wikipedia, these are for overwing exits.

The use of overwing exits in a ditching varies from airline to airline. On aircraft fitted with overwing exits, there is typically a raised escape rope bracket (about a third of the way from the door) attached to the wing's upper surface and typically painted yellow. This is accompanied by an escape rope found in the frame of the exit after opening the hatch. Once this rope is attached to the escape rope bracket, it will aid passenger evacuation onto the wing to await rescue or to enter the water (depending on the airline's procedures). On aircraft with life rafts to be launched via the overwing exit, the wing will be used to provide a boarding platform onto the life raft. On certain regional aircraft, the overwing exits are the only escape route in the event of a ditching.

Farhan
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  • Thanks, this is what I was looking for. Isn't having ONLY overwing exits on regional craft a bad idea if a wing mounted engine catches fire or if the turboprop hasn't stopped spinning? – shortstheory Mar 21 '14 at 10:13
  • Most larger airplanes have several doors, not just over the wings. Depending on the situation, some or all can be used. In case of Flight 1549, the overwing exits were the most important ones. – Farhan Mar 21 '14 at 19:52
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    @shortstheory "... the only escape route in the event of a ditching" (emphasis mine). If you've ditched the plane, the wing-mounted engines are underwater, which will extinguish the fire. – David Richerby Jul 01 '15 at 10:09
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    I can't believe I never doubted my assumption that these were lift points for removing the wing for maintenance. – Todd Wilcox Jul 01 '15 at 12:05
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    @ToddWilcox Do you know what: I thought they are yellow because the Airbus I first noticed them on was a Lufthansa one and that's (one of) their CI colours. – PerlDuck Feb 21 '17 at 13:07
  • @DavidRicherby: So do the forward entry doors magically jam shut in a ditching? – Vikki Apr 21 '19 at 00:19
  • @Sean If you disagree with the quote, take it up with its author, not the person who quoted the person who quoted it. – David Richerby Apr 21 '19 at 13:00
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Likely they are tethering points for emergency exit ropes. The Boeing 737-800 has the same type of hooks. See top row from the water evacuation procedures:

Boeing 737-800 evacuation procedures
(Image source)

Farhan
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David Kryzaniak
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  • From this analysis of Hudson ditching, in which life lines were not extended by passengers opening the overwing exits: "Despite a regulation requiring the life lines at overwing exits [...] circumstances in which they could be used effectively after ditching have been unclear [...] The NTSB concluded that life lines could have been used to assist Flight 1549 passengers on both wings, “possibly preventing them from falling into the water.”" – mins Oct 24 '23 at 11:26
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The inner ones are mounting points for evacuation slides and/or a rope handrail since the wing is likely to be slippery and wet. Several aircraft including the A320 and B737 have additional overwing life rafts when ditching. You clip in a rope either at these points or in a hook at the window, throw it overboard, and give it a sharp tug to inflate. Joyous passengers will then board the life raft.

pic

Source

The outer one works as a harness securing points for the maintenance guys working on the wing, but I guess this could be used for the first purpose as well if you would want to gather everybody around one wing or something.

Thunderstrike
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    Perhaps the OP should read the safety information card in between looking out the window and taking pictures of the wing. ;-) – Sports Racer Jun 02 '15 at 13:35
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    Bordering on mean. ;-) – ljwobker Mar 26 '18 at 22:39
  • @SportsRacer: Many passengers who ditched on the Hudson exited the aircraft without life jacket (location on label overhead) or flotation seat cushion (as prescribed in safety card). "17 % watched most of the preflight safety demonstration, 13 % watched some of the demonstration and 8 % read the safety information card*" (from analysis). The fact nobody died during the evacuation is actually a second miracle due to many "fortuitous circumstances*", according to the NTSB report. – mins Oct 24 '23 at 11:44