Variable Stability In-Flight Simulator


Calspan has been the worldwide leader in developing and operating variable stability In-Flight Simulators (IFS) since 1947. The variable stability airplane was conceived as a device that would permit in-flight variation of the flying qualities of an airplane so pilots could determine the suitability of these characteristics in actual flight.

Today, with a nod to the fact that history shows in-flight testing provides better answers than ground simulation, the concept of the variable stability airplane has progressed into true in-flight simulators that are routinely used as an extension of ground-based simulators, adding the real flight environment and real-world cues. Calspan Aerospace’s current fleet of four Learjet IFS permit the safe evaluation of aircraft flight control laws and handling qualities in a real flight environment—before the aircraft is even built.


The capabilities of our In-Flight Simulation team include:

  • Configuring the Learjet to fly just like a customer’s aircraft
    • Modifying the IFS Learjet’s programmable flight control laws to match the open-loop flight dynamics of the customer’s aircraft
    • Integrating customer control laws
      • Using customers’ production or prototype hardware and/or hosting the control laws within our aircraft computer
  • Flying aircraft safely all the way to touchdown
Flight Testing Simulation Gallery7


Calspan Aerospace customers that engage our expertise in In-Flight Simulation receive innumerable benefits, including:

  • Conducting evaluations in a real flight environment that includes fully representative motion cues and real-world visual cues
  • Augmenting their test teams with our experienced test pilots, who can fly and evaluate designs
  • Evaluating aircraft early in the design process, as soon as a stability and control model exists
  • Gaining the ability to find and correct deficiencies before fabrication of the actual aircraft begins
  • Taking advantage of safety features that include:
    • An on-board safety pilot to monitor aircraft response who’s ready to take control at the push of a button
    • An Automatic Safety Trip System that monitors aircraft limits to prevent unsafe flight conditions from occurring