• deranger
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    6 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@sub.wetshaving.social
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      6 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.

      • deranger
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        6 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.