#plane_maximum_altitude__planemaximumaltitude__ceiling  maximum altitude at which a plane can fly (under specified conditions)
  supertype:  #altitude.elevation__height  elevation especially above sea level or above the earth's surface
  subtype:  #absolute_ceiling  the maximum altitude at which an air plane can maintain horizontal flight
  subtype:  #combat_ceiling__service_ceiling__serviceceiling  altitude above which a plane cannot climb faster than a given rate

No statement uses or specializes #plane_maximum_altitude; click here to add one.