Questions re: ballista, scorpio crews

[sraoses]

Ballista: my understanding is that a normal sized ballista would require a somewhat large crew. While I realize that for construction, transportation, and maintenance purposes many men might be needed, how many would be needed for its use in battle given it was to remain in one place? If a ballista's draw weight was such that the winch could be drawn with the power of two men, could it be effectively deployed by only those two men, and if so, what made it worth it for more manpower to be allocated to it beyond the point of setting it up? Would it have often been the case that some of the ballista crew would be re-allocated to melee duty?

Scorpio/cheiroballista: I can imagine it running more efficiently with two operators, but is it more likely to have been used by a single operator or two? Might there have been main operator with an assistant who would only stay with him up to a certain point?


Thanks in advance