I'm on a message board for people who like to read and write. Somebody is writing a fantasy book and wants to know if it's really possible for two people to ride a horse when one of them is unconscious. (OK, I guess the unconscious person isn't really "riding" lol). Someone there who has horses said it would be possible, but I wanted to know what some more experienced horse people thought. How long could a horse gallop carrying two people to begin with?
It would depend on the size of the horse, how good of shape it was in, the size of the people, etc. The simple answer is yes, a decent sized horse in moderate physical condition can carry 2 average sized people at a canter or run for quite a ways. It would be harder on the horse if one of the people was 'dead weight' though because that person would be bouncing and flopping around. Also, it would mostly depend on how strong the second rider was and if they had the physical ability to a) get the unconsious person on the horse, b) keep the unconsious person balanced so that they didn't fall off.
I think the crux of the matter would be the strength and riding ability of the second rider. Horses often carry a sheep/calf along with the rider which would be similar, but it is a heck of a job trying to stop them falling! So if the second rider is a big, burly fantasy hero type, then yes I would it is possible. If it was a waif of a damsel in distress, then no.
Might be easier if the rider fashioned a travois for the injured party. Native Americans used to do this using two poles lashed to either side of horse like an A frame, wide end trailing on the ground. Straps or wooden cross pieces were lashed in between poles to serve as a carrier. Horse can carry rider and pull injured person behind it at the same time. You can google it for more info.