I like the linked hose ladder idea. The idea of packing bulky equipment into a small space and inflating it as needed is very appealing. The problems: it needs a lot of water - available in the city, but probably to be trucked in outside the city. Also if the water leaks out of a tear out the thing
might catastrophically fail.
The vacuum kernel hose ladder is similar in that it is a floppy bag for transportation. It is bulkier than the hose ladder because it is full of "vacuum kernels" - small firm rubber items, in the shape of jacks (the toy), and partly filled with air.
The VKHL is lifted into position with a pole, and then an attached pump evacuates the air within it. With this, the kernels within become less free to move about as they are squeezed tight by atmospheric pressure outside the bag. The kernels also expand (as they contain gas at atmospheric pressure) and interlock. The VKHL becomes rigid in position. On stopping the pump and opening a valve, air flows back in and it will sag back into formlessness for easy transport.
Advantages: 1 - less catastophic failure. If a rip opens, the attached vacuum pump can compensate to some degree by removing air as it enters through the rip.
2 - no water. The water required for the hose ladder is bulky to haul around and is wasted after the ladder is used. The vacuum pump for the VKHL is run off the truck engine.
3 - more flexible as regards form. A metal cherry picker can extend and retract. The hose ladder inflates to a predetermined form. The VKHL will stay in any form it is placed in once the vacuum is turned on and the kernels interlock. The kernels can be removed and placed into a different form (example - dam, wall, bridge, corral, water pool, giant spider) for other temporary uses - This makes the VKHL more versatile.
4 - easily transportable. The VKHL is bulkier than the hose ladder, but less bulky than a cherry picker.
5 - potentially very large - given that the bulk of the VKHL is made of the kernels, the VKHL and related kernel-containing vacuum structures can be very large and remain light. An example might be a very tall ladder suitable for skyscraper rescue - a metal or water containing ladder will be prohibitively heavy / high pressure. The VKHL will be comparatively light.