Description

Modern aircraft design permits high rates of climb or descent. High vertical rates help to achieve better fuel efficiency and allow for flexible use of airspace. After take off, high climb rates are desirable for noise abatement purposes.

Effects

A high rate of climb or descent can trigger operationally unnecessary (nuisance) Airborne Collision Avoidance System (ACAS) RAs.

A high rate of descent during an approach to land maybe a contributing factor in unstabilised approaches.

While high vertical rates help air traffic controllers in more efficient handling of traffic in their sector (aircraft reach the cleared level quicker), the controllers should be aware that high vertical rates may trigger unwanted TCAS RAs and, consequently, a deviation from the current clearance.