For aircraft coming from sector 45 requesting FL180, what should the student do?

• A. Tell the R-side that FL180 is not usable.
• B. Issue a usable altitude, enter that altitude in the data block, and coordinate with the R-side.
• C. Climb to FL200 without coordination.
• D. Do not tell the R-side that FL180 is not usable.

Answer: (B)

Coordinated handoffs and using a usable altitude when the requested level isn’t available is how we maintain safe separation across sectors. When an aircraft from sector 45 asks for FL180, you first determine whether that level can be used given current traffic. If FL180 isn’t usable, you issue a different altitude that is usable, enter that assigned altitude into the data block so the system and both sides have a clear record, and then you coordinate with the R-side to confirm the new clearance and plan the handoff. This keeps the flight on a clear altitude path and ensures both sectors are synchronized. Simply telling the R-side that FL180 isn’t usable wouldn’t provide the actual clearance and would leave no documented altitude; climbing to FL200 without coordination risks conflict; and not informing the R-side at all would break the coordination process. Therefore the correct action is to assign a usable altitude, update the data block, and coordinate with the neighboring sector.