> Do runways have some sort of barrier between them and the next "important" thing. It seems like that would be prudent both for cases like this

Ha, Jeju Air Flight 2216 smashed into a barrier on the second landing attempt in Muan last year [0], and people commented "How could there be a barrier at the end of the runway, so obviously stupid, irresponsible", etc.

Now a plane does not smash into a barrier at the end of the runway and people suggest putting barriers at the end of the runway.

Don't mean to attack parent post, but may I suggest that

a) hordes of experts have thought long and hard about these issues, and it is unlikely that you can encounter this for the first time as a lay person and come up with a solution that has eluded the best engineers for decades ("why don't they attach a parachute to the plane?"), and

b) we are very close to an optimum in commercial aviation, and there are few if any unambiguous ("Pareto") improvements, but rather just tradeoffs. For example: You leave cockpit doors open, terrorists come in and commandeer the plane to turn it into a weapon. You lock the cockpit doors closed, and suicidal pilots lock out the rest of the crew and commandeer the plane to turn it into a weapon of mass-murder-suicide.

There are no easy answers.

[0] https://en.wikipedia.org/wiki/Jeju_Air_Flight_2216

ETA: In 2007 an A320 overran a runway in Brazil and crashed into a gas station, killing 187 pax & crew + 12 on the ground. https://en.wikipedia.org/wiki/TAM_Airlines_Flight_3054

One improvement is a bed of concrete at the end of the runway that will catch the wheels and slow an airplane down to a stop. Pretty much everyone agrees it’s a good idea but it’s not always possible due to space needs or cost. https://en.wikipedia.org/wiki/Engineered_materials_arrestor_...

After 9/11, unlock the pilot doors. The passengers will revolt against any attempted aircraft hijackings.

We need members of the public ready to help in a situation where a pilot goes crazy, and they can’t help with a locked door making it impossible for them to enter.

The solution is to "free" the perimeter of takeoff/landing. Bonus: People don't have to chose to work/live in these noisy areas. I understand some areas have challenges to come up with space but the US has tons of space and maybe the sea should be used to host these airports.

Or a ramp with "one-way teeth" that stops it with gravity and stops it from sliding back down with teeth.