Top of descent
Encyclopedia
In aviation
, the top of descent, also referred to as the TOD or T/D, is the computed transition from the cruise phase of a flight to the descent phase, the point at which the planned descent to final approach altitude is initiated. The top of descent is usually calculated by an on-board flight management system
, and is designed to provide the most economical descent to approach altitude, or to meet some other objective (fastest descent, greatest range, etc.). The top of descent may be calculated manually as long as the distance, air speed, and current altitude are known.
Aviation
Aviation is the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is derived from avis, the Latin word for bird.-History:...
, the top of descent, also referred to as the TOD or T/D, is the computed transition from the cruise phase of a flight to the descent phase, the point at which the planned descent to final approach altitude is initiated. The top of descent is usually calculated by an on-board flight management system
Flight management system
A flight management system is a fundamental part of a modern airliner's avionics. An FMS is a specialized computer system that automates a wide variety of in-flight tasks, reducing the workload on the flight crew to the point that modern aircraft no longer carry flight engineers or navigators. A...
, and is designed to provide the most economical descent to approach altitude, or to meet some other objective (fastest descent, greatest range, etc.). The top of descent may be calculated manually as long as the distance, air speed, and current altitude are known.