air traffic service unit

The message would then be encoded and relayed to other weather offices and air traffic service units.

All Air Traffic Service units will provide an FIS to any aircraft, in addition to their other tasks.

The pilot is, in addition, provided with the capability to request conditional clearances (downstream) and information from a downstream air traffic service unit (ATSU).

An FIS shall be provided to all aircraft which are provided with any ATC(Air Traffic Controller) service or are otherwise known to Air Traffic Service units.