Parallel runway operation | EDDL and EDDK
Due to the proximity, the parallel runways at Cologne/Bonn and Düsseldorf airport have to be considered as one runway in terms of runway separation.
Treatment as one runway means that only one aircraft may use either runway at any time. This excludes taxiing, line-up instructions on the parallel runway and clearances to cross the parallel runway.
For example, if there is approaching traffic on runway 23R, a take-off clearance on runway 23L can be given safely until the arriving traffic runway 23R is at approx. 3NM (provided the departing traffic has already completed line-up). Depending on the approach speed, this 3NM can also be undercut, but runway separation must be unsured at all times. This means that a previously departing aircraft must either have crossed the end of the runway or initiated a turn before the landing aircraft corssed the treshold on the parallel runway. The simultaneous use of both runways, e.g. for a northbound takeoff and a southbound takeoff, is never possible, regardless of aircraft type or flight rule!
This rule applies to Cologne/Bonn as well.
In the event of a missed approach, radar separation must be unsured between two IFR flights. Especially in Düsseldorf, due to the proximity of the two runways, this requires active action by the tower controller, who must separate potential conflicts and coordinate them with the approach controller.
Not withholding takeoff or landing clearance
Since the parallel runways in Düsseldorf and Cologne are considered as one runway with regard to the runway separation as described above, the procedure "Not withholding takeoff or landing clearance" can be applied, considering the parallel runways as one.
Wake turbulence separation
Since the runways in Düsseldorf are less than 760m apart, wake turbulence separation must be ensured.
In Cologne, the runways are far enough apart (1150m) so that wake turbulence separation does not have to be ensured. This allows approaching IFR traffic to overtake VFR traffic. However, as described above, the runway separation must be maintained.