A numerical strategy for the efficient determination of 4-vortex wakes, consisting of two counter-rotating vortex pairs, with low induced rolling moments after the unstable merging of inner and outer vortices is proposed. After a systematic investigation of generic 4-vortex systems in a second step an airliner geome- try in high-lift configuration is modified such that it produces a vortex wake similar to the identified opti- mal 4-vortex system. The configuration modification is done using simple design rules. For verification of the existence of a similar 4-vortex system the wake vortex of the modified airliner configuration is simu- lated up to the extended nearfield in a final step. Two 4-vortex configurations are considered in the present paper, different only in the vortex spacing ra- tio. A maximum reduction of rolling moment down to 44%-52% of the rolling moment of a reference 2-vortex system is achieved within a distance equivalent to 2.89 NM for a real size Airbus A340. The realization of 4- vortex wakes behind an individually modified high-lift configuration similar to the afore determined promis- ing generic 4-vortex configurations is demonstrated.
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