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Rossiya Airlines flight FV5625 to Antalya suffered an incident at the gate when a passenger opened an emergency exit (seems to be the L3 door, from what I can tell) "because they felt too hot", deploying the slide.

In a discussion on the news item, someone remarked that it was lucky that it didn't happen in flight, which of course should be impossible.

But that made me wonder whether that emergency exit is a plug door, or if there's another mechanism preventing the door being opened in flight.

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  • $\begingroup$ What is curious is the door slide was armed at the gate (it was not "on the runway"). $\endgroup$
    – mins
    Jul 12 at 15:26
  • $\begingroup$ @mins, you're right, I'll correct that. $\endgroup$
    – SQB
    Jul 12 at 15:26
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    $\begingroup$ @mins It is not unusual to have the doors armed at the gate. At least for some airlines it is procedure to arm all doors before the engines are started to make sure the aircraft can be evacuated quickly in case of a fire during starting. $\endgroup$
    – Bianfable
    Jul 12 at 15:35
  • $\begingroup$ @Bianfable: Makes a lot of sense of course. $\endgroup$
    – mins
    Jul 12 at 18:40
  • $\begingroup$ I always thought that armed was the default state of all doors. "Armed, unless..." $\endgroup$
    – SQB
    Jul 12 at 20:30
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Yes, all 10 passenger entry doors on the 747-400 main deck are plug-type doors:

The main deck passenger entry doors are used to enter and exit the airplane, and serve as emergency exits. The ten passenger entry doors are paired along the airplane fuselage. [...]

The entry doors are translating, plug-type doors. During opening, the door first moves inward and upward, then translates outward and forward.

(Boeing 747-400 FCOMv2 1.50.3 - Airplane General, Emergency Equipment, Doors, Windows - System Description, emphasis mine)

This will make accidental opening of these doors while the aircraft is pressurized impossible.

Based on the picture from the video it was the L2 door, right in front of the wing (L3 is the overwing exit):

747-400
(YouTube: Passenger deploys emergency slide on Rossiya Airlines 747)

The passenger who opened the door probably did not know about the ARM state of the door:

Passenger Entry Door 1, 2, 4, and 5 Slide/Raft Operation

When the door mode select lever is in ARM position and the door operating handle is rotated 180 degrees, the door begins to open and the power assist opening system activates.

The flight attendant must release the door operating handle and continue to assist the door opening motion by using the handles on the door and on the door surround panel until the door is in the full open and latched position. The door-mounted escape slide/raft deploys and inflates. [...]

When the door is to be opened from the interior and slide deployment is not desired, the door mode select lever must be in DISARM position.

(Boeing 747-400 FCOMv2 1.50.3 - Airplane General, Emergency Equipment, Doors, Windows - System Description)

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  • $\begingroup$ Do you know what is the pressure differential required for preventing the door to open airborne? $\endgroup$
    – mins
    Jul 12 at 18:46
  • $\begingroup$ @mins I guess that depends on how strong you are. If the door is about 1m² in area (not sure how large it exactly is), then you'd need about 7kN of force to overcome 1psi pressure difference, equivalent to lifting up about 700kg. $\endgroup$
    – Bianfable
    Jul 12 at 19:12
  • $\begingroup$ It's going to be 1m2 at least, probably closer to 1,5m2 based on this short clip of a 747-400 door. Apparently finding the exact dimensions of cargo doors is a lot easier than finding those of L1-L3 doors. $\endgroup$
    – Mast
    Jul 12 at 23:16

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