Personnally, as IMCDB , IGCDB does already exist, I would find much more logic to create separately:

IMADB (Aircraft meaning = all types of flying machines. Balloons (powered or not), gliders, airplanes, helicopters and space rockets, the case of weapons rockets is specific and I don't know if it should have its place ?)

IMTDB (Locomotives , anykind of them + wagons)

IMSDB or IMBDB (Ships or Boats)