Abstract: A miniature electric track and train system which provides a simple and inexpensive arrangement for the simultaneous independent operation of at least two electric engines on the same track.

Abstract: Method and apparatus are provided for the tactical nagivation and communiion of a community of aircraft. Each of the aircraft in the community is provided with an inertial navigation system capable of providing accurate short term navigational information and a time synchronized ranging system capable of providing accurate long term navigational information. One of the aircraft is designated as the airborne control unit and establishes a relative grid coordinate system within which the community of aircraft operate. The origin of the relative grid is established by the airborne control unit. When stationary ground time synchronized ranging system units are present, highly accurate georeferenced information may be supplied to the airborne control unit by operation of its time synchronized ranging system. When such ground units are not present, accurate georeferenced information may be obtained by the airborne controller from navigational systems such as satellite, Loran or Omega systems.