Si tratta del ramp slide, cioè sulle overwing exit, e non dello scivolo delle porte, anche se questo non spiega ancora il come.
Qualche dettaglio qui:
United Airlines Boeing 767 Loses Evacuation Slide Mid-Air
On 17th July, 2023 a United Airlines Boeing 767 lost an evacuation slide mid-air while it was on final approach to Chicago's O'Hare. Pilots remained unaware of the situation until the maintenance workers noticed it on landing.
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