For which conditions are minimum climb altitude or gradient specified for departures?

Minimum climb altitude or gradient for departures is specified in specific sectors of the departure. This is primarily due to air traffic control and safety considerations in areas where airspace conflicts might arise or where terrain may pose risks. In certain sectors, especially near obstacles or where airways converge, it is critical to maintain specific altitudes to ensure safe and effective separation from other aircraft and to avoid terrain.

While busy airports may have specific requirements, the necessity for minimum climb altitudes or gradients is not exclusively linked to airport traffic levels. Similarly, bad weather conditions may affect overall operations but do not inherently mandate climb altitudes — they are part of standard departure procedures regardless of weather. Finally, while controlled airfields have regulations, the specific requirement for minimum climb altitudes is not universally applied to all departures but rather to designated sectors important for safety and operational efficiency.