The IEA Wind TCP Task 29 can be considered the successor to IEA Wind TCP Tasks 14,18, and 20. All these Tasks focused on detailed aerodynamic wind turbine measurements. The first three phases of Task 29 (often denoted as Mexnext-I to III) ran from September 2008 until December 31, 2017 and . They analyzed the wind tunnel measurements which became available in December 2006 within the EU project Mexico and in the later New Mexico project which was carried out in June/July 2014. In these projects detailed aerodynamic measurements were carried out on a wind turbine model with a diameter of 4.5 m, which was placed in the largest European wind tunnel, the LLF facility of the German Dutch Wind Tunnel, DNW with a size of 9.5 x 9.5 m2. Within the (New) Mexico project it was not only pressure and load data which were measured (this was done in Tasks 14,18, 20 already) but in addition detailed flow field data were taken with the Particle Image Velocimetry (PIV) technique.
The fourth phase of Task 29 started on January 1, 2018 and it will end on December 31, 2020 Although the basic goal of Phase IV, at first sight looks similar to the goal from the previous phases, i.e. improvement of aerodynamic models for wind turbine design codes, the goal is now reached by means of full scale field measurements from the Danish Danaero experiment on a 2MW turbine. This is a step closer to the operation of wind turbines in real life conditions since in the first phases wind tunnel measurements were used. The fact that Phase IV relies on Danaero Field measurements makes the name Mexnext not applicable anymore.