Second The supplies they had on the Eagle included a grappling hook, knife, hatchet, but not a single Berretta 92, colt .45, M16. In other words they had energy beam weapons and weapons from the 1800's, not a single projectile weapon.
Yeah, I have to admit it was a bit of a plot hole not to have some sort of projectile weapon available. I would chalk it up to tv ratings (fantasy violence from ray guns always seems to be considered less serious than a six-shooter, for some reason), but DD is so danged violent and bloody by the standards of the day, it seems a bit of a stretch to say they couldn’t have worked in had a firearm of some sort.
Heck, even a speargun or a crossbow would have worked!