I've been doing a campaign for a little while now, and am planning on a having the ship visit a feudal world at some point. (I.E. Whenever the Navigator happens to blow his Navigation tests badly). Since my guys haven't yet obtained any ground vehicles, and there's going to be factors in play to prevent them using aircraft too often, I was wondering what kind of rules could be used for traveling/combat on horseback.

For instance, I was thinking of giving some bonus damage when making a charge on horseback, or having horses become lamed after taking a certain amount of damage (possibly with a toughness test involved).

In my detailed campaign the party paid for the Captain of their medium cavalry company's mount to have bionic legs after it took a melta hit and lost one when I said he would take a 20% Morale loss for losing it, vat grown horses are available so replacing them should be easy on various empire worlds, if you don't want to sell them a growth vat. Breeding and training war horses takes a very long time to replace though.

As for the rest, A minor strength/damage bonus for close combat attacks only and the skill Pilot (Horse/Animal/Mount) is required or dump the usual -20% to hit on them. Guess it just depends what weapon they are using, a shocklance should def' grant a huge initiative bonus but only for the first round.