Worldwide Aeronautical Route Planner (WARP)
WARP is an optimizing aircraft router that is deployed as the core of a route planning system in operation at the U.S. Air Force’s Air Mobility Command. The system is used to route cargo aircraft worldwide.

WARP uses sophisticated search techniques to produce routes that minimize the burn of fuel while satisfying all other flight constraints. The routing process factors in the effects of weather, aircraft performance, and areas that must be avoided. WARP can also determine the optimal fuel load required to accomplish a mission. 

The diagram shows a route produced by WARP for a flight from Dover Air Force Base in the United States to Ramstein Air Base in Germany. It saves thousands of pounds of fuel when compared with other contending routes, including the shortest-distance route between the airports.

WARP allows flight planners to specify a variety of parameters, including:
•    Departure and destination coordinates or airports
•    In-flight checkpoints or coordinates
•    Departure time, destination time, or in-flight time points
•    Departure fuel, destination fuel, or in-flight fuel values
•    Payload
•    In-flight fuel offload (tanker) or onload (receiver)
•    Weather overrides
•    Aircraft parameter overrides
•    SIDs and STARs
•    Tracks (e.g., North Atlantic Tracks or Flex Tracks)
•    Holds and orbits
•    Alternate and recovery airports
•    Routing type (Airway, Navaid, Direct, Great Circle) for any flight segment
•    Aircraft cruise throttle settings
•    In-flight altitude constraints
•    Areas which must be avoided

WARP typically solves even complicated routes in less than 30 seconds.