How are suitcases secured in airliner cargo holds?

I've never seen the inside of the baggage storage area, so I wonder--do they just throw the bags in haphazardly, do they have shelves, slots, straps, etc.? Do they pile bags on top of other bags? Is a person inside manually placing the bags in place? Do they have a conveyor inside the plane? Etc.How are suitcases secured in airliner cargo holds?
Some older aircraft had a shelf system that we could stack bags on and then electronically move that row back, opening up another shelf. They aren't always reliable. Larger airplanes that have long cargo bins sometimes have a belt system in the floor. Luggage is stacked on its side up to the two inch minimum space/gap required for the fire control systems in the ceiling. Depending on the cargo bin size, 1-2 people work ( on their knees ) stacking the baggage/cargo tightly to minimize movement but without damaging the items. Once the bin is full or all items that need to be loaded, have been, cargo nets are put into place ( attaching floor to ceiling at the bin door ) to keep items from moving. Widebody airplanes have container systems that we preload on the ground and then machines lift them up to the airplane door and load them inside. Floor locks are used to hold them in place. Everything is loaded with the airplanes weight and balance in mind. Can't make it too heavy to fly or too heavy one way or the other to where it won't fly level without alot of adjustments by the pilots, burning alot more fuel. Regardless of the airplane type, it still takes people to manually load them up.How are suitcases secured in airliner cargo holds?
do they just throw the bags in haphazardly,


Yes. pretty much.





do they have shelves, slots, straps, etc.?


Mostly no.





Do they pile bags on top of other bags?


Yep.





Is a person inside manually placing the bags in place?


Often yes.





Do they have a conveyor inside the


Not on any planes than I'm aware of.