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Überblick

Overwing emergency exits are supplemental exit paths positioned at the wing root area of narrowbody and some regional jet aircraft, providing additional egress capacity that contributes to meeting the 90-second full-evacuation requirement. Designated as Type III exits under FAA classification (smaller than Type I main cabin doors and without attendant-operated slides), overwing exits are typically designed for passenger self-operation — any able-bodied passenger can open the exit and evacuate without crew assistance. On single-aisle aircraft such as the Boeing 737 and Airbus A320 families, overwing exits are a critical component of total exit count, and their location over a relatively flat wing surface provides a natural stepping platform for evacuees before they slide down the wing trailing edge to the ground.

Funktionsweise

Overwing exits are opened by rotating or pulling a handle that releases the door latch, then pushing or pulling the hatch inward or outward depending on design. On the Boeing 737-800, the overwing exit hatch swings inward and is stowed against the seat or overhead as the opening is cleared. On the Airbus A320, the exit plug is pulled inward and then placed on the seat or floor. Placard instructions adjacent to each exit provide illustrated steps for opening; FAA regulations require that an unassisted able-bodied adult can open a Type III exit within a specified time limit in representative conditions including smoke and low lighting.

Once open, passengers step onto the wing surface — which is typically non-slip due to abrasive strips or textured paint — and make their way to the wing trailing edge, where they slide or step to the ground. The distance from wing trailing edge to the ground is approximately 2–3 metres on narrowbody aircraft, making this a viable egress path without additional equipment. Some aircraft, including newer 737 variants, have added a slide-assist device or inflatable step at the overwing exit to reduce the jump height and injury risk from the wing-to-ground step. Overwing exit rows are designated as exit row seats and passengers seated there are screened during boarding for physical ability to operate the exit.

Hauptkomponenten

Exit Hatch: Lightweight composite or aluminium plug designed to be quickly removable and stowable within the cabin footprint. Must withstand fuselage pressure differential in flight without the complex latching mechanisms of main cabin doors.

Opening Mechanism: Recessed handle with latch release requiring a defined operating force. Gust locks may prevent the door from being blown back into the fuselage after opening in high-wind conditions.

Wing Anti-Slip Surface: Abrasive strips, textured paint, or moulded ridges on the wing upper surface provide traction for evacuees. These require inspection and renewal at maintenance intervals.

Exit Row Seat Configuration: Seats adjacent to overwing exits have additional legroom to allow the hatch to be stowed, and may lack under-seat stowage to maintain a clear evacuation path. Seat-back literature and placard instructions detail exit operation.

Escape Path Lighting: Floor proximity lighting directs passengers from the aisle to the overwing exit. Some aircraft include lighting on the wing surface itself to guide evacuees to the trailing edge in low-visibility conditions.

Anwendungen bei Flugzeugen

The Boeing 737-800 has two overwing exits per side (four total), each serving rows of passengers. The Airbus A320 family similarly uses Type III overwing exits. Wide-body aircraft such as the Boeing 777-300ER and Boeing 787-9 do not typically require overwing exits because their large Type A main cabin doors provide sufficient exit capacity for the passenger load. The Airbus A380-800, with its unique double-deck configuration, uses main deck Type A and Type C exits without traditional overwing Type III exits, relying instead on its high number of main and upper deck door exits.

Advantages & Limitations

Overwing exits provide significant additional exit capacity on narrowbody aircraft at minimal structural weight penalty. The wing surface serves as a natural landing platform for evacuees, reducing the drop height compared to main cabin floor-level exits. A key operational limitation is that overwing exits are unassisted — there is no crew member positioned there during normal operations, and passenger willingness and ability to operate the exit under stress is variable. Accident investigations have found that passengers in exit rows sometimes fail to open exits promptly, reducing overall evacuation throughput. This has driven improved exit-row screening procedures, passenger briefing requirements, and for some operators, the introduction of exit-row seat assignments with pre-flight capability checks by cabin crew. In the case of a post-crash fire close to the wing — particularly near fuel tanks — the overwing exit path may be compromised, requiring passengers to redirect to main cabin doors.