Do you really have the available runway distance published?

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declared distances

Declared distances for the Naples Municipal Airport located in the Chart Supplement.

In the Chart Supplement entry for many airports, especially those frequented by jet aircraft, you’ll see a collection of runway distance information that may differ from the runway length information published on the airport diagram. These declared distances represent the maximum distances available and suitable for meeting takeoff, rejected takeoff, and landing distance performance requirements. The airport owner provides the declared distances for inclusion in the Airport Master Record and the Chart Supplement for each operational runway.

While the declared distances formally apply to the certification and operation of turbine aircraft, it is valuable information to all pilots.

Declared distance information includes:

  • TORA (Takeoff Run Available);
  • TODA (Takeoff Distance Available);
  • ASDA (Accelerate Stop Distance Available);
  • LDA (Landing Distance Available).

For runways without published declared distances, the declared distances are equal to the physical length of the runway unless there is a displaced threshold which would shorten the distance available for landing by the length of the displaced threshold.

Declared distances can also increase runway use. Declared distances that use a clearway or stopway can increase TODA or ASDA can provide turbine aircraft additional performance capability and increased maximum allowable takeoff weights.

TORA (TakeOff Run Available)

The TORA is the length of runway available for takeoff run requirements. When the full runway beyond the start of takeoff is available for the takeoff run, the departure end of the TORA is located at the departure end of the runway. A reduced TORA can be used to mitigate incompatible land uses in the departure runway protection zone (RPZ) or to mitigate environmental impacts.

shortened TORA

Example of a shortened TORA.

TODA (TakeOff Distance Available)

The TODA is equal to the TORA plus the length of any remaining runway or clearway beyond the departure end of the TORA available for satisfying takeoff distance requirements. A clearway is a rectangular area beyond the end of a runway cleared or suitable for use in lieu of a runway to satisfy takeoff distance requirements; however, any portion of the runway extending into the clearway cannot be used for takeoff run calculations.

Standard TODA

Example of a standard TODA at the departure end of the runway.

extended TODA

Example of an extended TODA.

ASDA (Accelerate Stop Distance Available)

The ASDA is the length of runway plus stopway available for satisfying accelerate-stop distance requirements for a rejected takeoff. A stopway is an area beyond the takeoff runway which is able to support the airplane during an aborted takeoff without causing structural damage. A stopway also has to be designated by the airport for use.

LDA (Landing Distance Available)

The LDA is the length of runway available for satisfying landing distance requirements. The LDA begins at the threshold. A stopway cannot be part of the LDA.


Example of ASDA extending beyond the LDA.

Eric Radtke