How will such wall prevent a weighted line connected to a rope ladder from being tossed/shot from one side over to an accomplice on the other side?
Our sniper.
Put a Electric Fence on top!!
There is no wall that could be designed and built that could not be breached somehow. But making it very difficult deters the easy crossing and restricts the effort to organized operations, which are easier to detect and stop. (IMO)
For instance, the cylinder at the top with a vibration sensor and alarm would alert people that a rope or cable has been landed on the top of the wall. It's going to take a while to hoist people up 30 feet. We should be able to get people to the location before they can get too many bodies over the wall. Fill the foundation with sand and piles to prevent tunneling. The size of the hole and the time it takes to excavate it could be observed by daily inspections.
The fully armed US guards on the other side still get to play a role in stopping illegal migration. Imagine the guy climbing over before you getting his head exploded by a rifle shot, but that aint gonna slow you down none at all.
That’s where see-thru comes into play...
There has to be favorite crossings and they will change....so when they move, we move.
See through seems the best. Reward land owners for reporting them. Of course half are likely to be taking bribes already....that's the Mexican way.
The wall is a force multiplier it doesn’t replace the need for a manned border. It enhances border security it isn’t a stand alone solution.
“How will such wall prevent a weighted line connected to a rope ladder from being tossed/shot from one side over to an accomplice on the other side?”
The main obstacle is just the sheer height of the wall, like a three story building. Testers had a hard time getting a grappling hook up to that height by hand, though it could be done. Another thing that testers experienced, was that somewhere between 16 and 20 feet, it started to get scary high for climbers. Thirty foot drops are more often fatal than not (those not killed, are badly injured, no walking it off). Non-commando men, women and children will be strongly deterred by the sheer height. It approaches a task for specialists, like rock climbers.
The other main deterrent to the rope ladder (or a regular ladder, with a rope to descend), is the kind of double barrier that is envisioned in urban areas - a no-man’s land between barriers, where there is no accomplice available on the other side, but rather a gauntlet of lights, cameras, sensors and Border Patrol.
How many folks, let alone malnourished illegals, have the upper body/core body strength to climb a rope ladder 30 feet and then climb down the other side.
And these test attempts didn’t even factor in any motion detection systems that will also be deployed.
FTA in response to your question:
The highly trained testers scaled 16 to 20 feet (4.9 to 6.1 meters) unassisted but needed help after that, said the official who described the assaults on the wall prototypes to the AP. Testers also expressed safety concerns about getting down from 30 feet.
Only once did a tester manage to land a hook on top of the wall without help, the official said. Tubes atop some models repelled climbing devices but wouldn't work in more mountainous areas because the terrain is too jagged.
Looks like height of the proposed wall is a vital part of making it really work. Indeed, one of the big problems for a climber is getting down after going up. A 30' fall is very impressive.