Are you telling me that the pilots are all common type rated on these variants, BUT the tow-bars are not interchangeable. Astonishing. Which nationality of the Airbus consortium is in the firing line for that one. Equally the crab-claw tug designers; but then again, this variant of AB is quite recent. The numpty who loaded the wrong tower at base might be getting buried in the sand for a short while. (n.b. Remember when you are up to your neck in the sand/poo make sure it's feet first)