(refuel plane2)
(fly-fast plane2 city2 city0)
(board person4 plane2 city0)
(fly-slow plane2 city0 city1)
(board person2 plane2 city1)
(debark person4 plane2 city1)
(fly-slow plane2 city1 city2)
(refuel plane1)
(fly-fast plane1 city2 city0)
(debark person2 plane2 city2)
; cost = 10 (unit cost)
