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AP4ATCO - Modern Aircraft Performance Parameters and Limitations

From SKYbrary Wiki




To gain an understanding of:

  • Interconnection of ICAO Aircraft Designators and aircraft performance parameters.

ICAO Aircraft Type Designator

In principle, ICAO allocates an Aircraft Type Designator to all aircraft heavier than ultra/micro light. A designator consists of not more than four characters and is primarily intended for use in flight plans and associated air traffic services messages. Each designator is, in principle, to be derived from the manufacturer’s model number or model name or, from a common military type number. Only one designator is assigned per aircraft type - a different designator for a variant or subtype will only be allocated when a difference in a performance is significant for air traffic services, or when no shared designator can be assigned.


To gain an understanding of the typical performance figures for specific aircraft type, explore the SKYbrary Aircraft Type Directory.

ICAO Wake Turbulence Category

The International Civil Aviation Organisation (ICAO) wake turbulence category (WTC) is entered in the appropriate single character wake turbulence category indicator in Item 9 of the ICAO model flight plan form and is based on the maximum certificated take-off mass, as follows:

  • H (Heavy) aircraft types of 136 000 kg (300 000 lb) or more;
  • M (Medium) aircraft types less than 136 000 kg (300 000 lb) and more than 7 000 kg (15 500 lb); and
  • L (Light) aircraft types of 7 000 kg (15 500 lb) or less.


  1. Super Heavy for Airbus A380-800 with a maximum take-off mass in the order of 560 000 kg. (see Airbus A380 Wake Vortex Guidance)
  2. Variants of an aircraft type may fall into different wake turbulence categories, (e.g. L/M or M/H). In these cases, it is the responsibility of the pilot or operator to enter the appropriate wake turbulence category indicator in the flight plan.
  3. B757. Some states apply a higher category to B757 aircraft than that suggested by the aircraft's weight.

Aircraft Approach Category (APC)

An aircraft approach category is a grouping differentiating aircraft based on the speed at which the aircraft approaches a runway for a landing.

  • Category A: Speed 90 knots or less.
  • Category B: Between 91 and 120 knots.
  • Category C: Between 121 and 140 knots.
  • Category D: Between 141 knots and 165 knots.
  • Category E: Speed 166 knots or more.

Quiz Questions:

Q1: The aircraft with an ICAO Type Designator "A321"has a WTC of

  1. L
  2. M
  3. H


Q2: The aircraft with an ICAO Type Designator "H25B"has a APC of

  1. A
  2. B
  3. C
  4. D
  5. E



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