This obviously refers to the cargo deck loading scene in TMP. A look at the actual statement from Andrew Probert ("The idea is that shuttles would normally take off from and land in the landing bay") does not suggest that tractor beams or ship generated antigrav fields were involved. If that applies to shuttles it probably also applies to workbees. Bob
The US is, as we speak, throwing billions of dollars into the F-35 Lightning II, a fighter fundamentally compromised by the space requirements of the lift-fan system one variant uses for STOVL capability. We've seen self-contained antigravs the size of clothes irons in TOS, I see no reason why a general-purpose utility vehicle/equipment control cab wouldn't incorporate the same kind of equipment to expand it's operational regime from one specific environment to, effectively, all environments.