Much of a pre-flight brief is conducted over a closed-circuit television system for all the air crews together (regardless of squadron) who are scheduled to take off, or "launch," at the start of any particular flight cycle (cycles generally are about 90 minutes; some aircraft usually fly a single cycle while others may fly for two or three cycles before returning). These briefs are broadcast from the ship's Air Operations Department and include general mission details (so that everyone is aware of what other crews will be doing), various procedures, radio frequencies and weather reports. Additional briefing may be conducted in other areas of the ship depending on the mission type. (Fighter/attack crews will generally brief in Strike Operations, for instance.)