Tim wrote:Actually it is used on airplane wings I found out.....
....slightly different from the golf ball-principle, but same principle...)
Tim, I followed the link. The golf-ball analogy is wrong - poetic licence on behalf of the journalist I'd guess!
The article is refering to a branch of applied aerodynamics call "Laminar Flow Control - LFC". Here a laminar boundary-layer is artificially maintained (instead of a turbulent boundary-layer) over all or part of an aerodynamic surface. Because the artificial laminar boundary-layer generates less friction than the natural turbulent boundary layer, the skin friction component of drag can be reduced.
However, although the aerodynamic drag reduction is well proven, the overall system benefit is highly dependent on both good engineering integration and economic factors: Energy balance, servicability, reliability, maintainability, affordability, safety, system mass and -for aircraft- the market price of fuel to name but a few...
The solution to this remains something of a "holy grail" within applied aerodynamics .... but that doesn't mean budding engineers, scientists, inventors shouldn't continue to work on solving these problems... a step towards which may be laser-drilling in terms of manufacturability.
Sorry for the long post, but the devil is in the detail !
Hope this helps...