B737 Slides off Christchurch Runway
Viscous hydro planing. The surface doesn't even need to be 'wet', just damp. The aggregate micro texture has been destroyed. No idea why Christchurch rwy should be giving this problem.
Unless, and surely not, some half-wit recently applied a rejuvenator to the runway surface and destroyed the micro texture and thus the medium-low speed friction.
The Kiwis are normally pretty good at the pavements stuff - I can't believe they could have messed up so badly.
The world of friction and wet runways is being 'wrung out' right now, and we'll be looking at things a bit differently in the years to come.