My D&D 5e Homebrew uses lots of Mounts and Vehicles (includes horse drawn wagon, naval warships, hover craft, and personal battlesuits).
While my current party has yet to use Vehicles, it is bound to happen.
For Mounts, PHB suggests using Animal Handling. However, I have been unable to determine a current skill that allows for Handling or Operation of Vehicles.
Which Ability would be the most appropriate to use for Vehicle Handling and/or Operation?
What skill would you use for Vehicle Handling and/or Operation?
Would it make sense to add a "Vehicle Handling" skill to cover Vehicle Operation?
Best Answer
Tool Proficiency in Vehicles
Many backgrounds, including the sailor and soldier, include proficiency in Vehicles (Land) or Vehicles (Water) as one of their two given tool or language proficiencies. For your specific homebrew examples, an additional Vehicles (Air) proficiency might be appropriate. Players can add their proficiency bonus to checks made to handle vehicles if they've got this proficiency. From the Mounts and Vehicles section of the SRD:
Such a proficiency "is not tied to a single ability, since proficiency with a tool represents broader knowledge of its use," (thanks to diego for this) and could use any ability score at the DM's discretion. For example, using your given examples, a check to repair a hovercraft's broken propeller might be an Intelligence (Vehicles (Air)) check, while a check to move a shut-down personal battlesuit by the player stuck inside might be a Strength (Vehicles (Land)) check.