• walden
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    229 days ago

    Definitely a strange crash, although it sounds like there was some mechanical stuff going on as a result of multiple bird strikes on the previous approach.

    Lots of airports around the world have EMAS which is designed to stop an airplane in this situation. Unfortunately this airport has a concrete wall instead. Google maps has it labeled as “Walls of death”, although I don’t know if that was recently added or if they’ve had that nickname for a while. https://maps.app.goo.gl/eX9Fp9RXeVkRB94L9

    • @[email protected]
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      8 days ago

      EMAS requires a certain pressure to break through the surface. It’s designed for gear down overruns, not belly landings. I don’t think it’d do much if it were installed in this case.

      From skybrary.aero:

      Additional assumptions for all designs are that:

      • an aircraft is still attempting to stop as the runway is exited
      • reverse thrust / reverse pitch is not being used as the runway is exited
      • the surface area leading to the EMAS bed has poor braking characteristics
      • there is minimal or no structural damage to the landing gear
      • there is no aircraft braking or use of reverse thrust / reverse pitch once an aircraft enters the EMAS

      That penultimate point is key. It’s not designed for a no gear landing, or even damaged gear landing. It adds friction by the gear sinking into the materials.

      • walden
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        18 days ago

        Typically yeah, but I think there was likely enough weight on the engine cowls to make the engines dig in to EMAS. I wonder if it has ever been tested.

        • @[email protected]
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          38 days ago

          Certainly wouldn’t have hurt, but I don’t think it would have done that much.

          From skybrary:

          Most installations to date have used a maximum 70 knots bed-entry speed.

          …and thats with gear down. I believe the Jeju plane was doing something like 130+ kts off the end of the runway.