ots logo

Solutions  • Technology  • Clients  • Company  • Contact

Worldwide Aeronautical Route Planner (WARP)


WARP is an optimizing aircraft route planning engine that is deployed as the core of the Advanced Computer Flight Planner (ACFP) route planning system in operation at the U.S. Air Force’s Air Mobility Command. ACFP is used to route cargo aircraft worldwide in addition to mid-air refuelling operations.

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 airspace restrictions. WARP can also determine the optimal fuel load required to accomplish a mission and/or the maximum payload that can be carried.

Warp Screenshot

The map above 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 is believed to save the USAF tens of millions of pounds of fuel every year.

WARP lets flight planners 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
  • Cost indexing capabilities to adjust speed, fuel and enroute time
  • Automatic speed adjustment to meet multiple control times in a single route
  • Payload maximization
  • Mid-flight payload changes (increase or decrease)
  • In-flight fuel offload (tanker) or onload (receiver)
  • Calculation of step climb locations when they result in fuel savings
  • Ability to degrade fuel burn rates for a specific route request/tail over the entire route or route portions
  • 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
  • Zone-based routing
  • Aircraft cruise throttle settings
  • In-flight altitude constraints
  • Areas which must be avoided
  • Equal Time Point (ETP) and depressurization calculations
  • Route re-winding (i.e., re-plan a route following the same ground path but using newer weather forecast and/or modified payload and/or modified departure time)
  • Support for full route planning (ICAO to ICAO), “retask” plans (mid-air to ICAO), “ground” plans (ICAO to mid-air), “overhead” plans (mid-air to mid-air)

Although it must accommodate non-linearities and non-monotonicities in aircraft performance data, and in many cases optimize fuel burn while simultaneously maximizing payload carrying capacity, WARP typically solves even complicated route requests in less than 30 seconds.