Who is responsible for changing and issuing the correct assigned altitude for KJAN and KMLU departures requesting FL180 when it is unusable?

• A. Pilot
• B. Radar Controller
• C. Supervisor
• D. Receiving Controller

Answer: (B)

Radar controllers are responsible for issuing and changing assigned altitudes within their radar sector, including when a requested flight level is unusable. They monitor the aircraft on radar, ensure vertical separation, and coordinate with adjacent sectors to maintain safe sequencing. When a departure from those airports requests FL180 but that altitude cannot be used, the radar controller evaluates alternatives and issues a new assigned altitude that keeps the aircraft separated from traffic and compliant with current restrictions. The pilot must comply with that ATC clearance, rather than choosing or changing the altitude themselves. The supervisor typically gets involved only for unusual outages or policy issues, and the receiving controller handles aircraft in the other sector or arriving traffic, not the initial departure altitude change.