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AO-0302 — Time Based Separation (TBS) for Arriving Aircraft -Transitional Step

The TBS Transitional Step proposes a change in the current ATM procedures that will enable ATC controllers to apply a 0.5NM fixed reduction of the ICAO wake turbulence distance-based radar separation minima between wake turbulence separated aircraft pairs in specified headwind conditions and/or delivering Spacing Minimum at a distance from threshold defined as a function of wind. Compression beyond the delivery point will result in reduction of spacing at threshold that allows time spacing to be maintained even in strong headwind. The level of operational applicability and benefits will depend on local wind conditions and runway orientation.

The intent is to mitigate the effect of headwind on final approach sequencing to recover capacity lost under strong headwind conditions. No automation or modification of ATC tools is foreseen. Recent wake turbulence validation activities show potential benefits to see a reduction in the distance based separation for arrival aircraft when conditions allow (headwind/crosswind).
In general the benefits will favour airports in areas with delays caused by strong headwinds. Airports that heavily rely on an operator's network based on transferring passengers will benefit from this procedure.
The major benefits are to be achieved when a single segregated runway is used for arriving traffic and during peak periods or when airborne holding creates delays. The actual benefits are dependent mainly on local wind conditions, of the usage, orientation and layout of the runway(s) and will allow improved maintenance of capacity during strong headwinds.
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Dependent OI Steps

Relationship Code Title Related Elements
Has successor AO-0303 Time Based Separation for Final Approach - full concept

SESAR Solutions: No associated data

PCP Elements: No associated data

Implementation Objectives: No associated data