Craven, A. H.2015-09-112015-09-111960-09http://dspace.lib.cranfield.ac.uk/handle/1826/9420Available data on the effects of suction and injection on skin friction are summarised and compared. It is shown that injection into a turbulent boundary layer can produce a skin friction coefficient lower than the laminar value at trio same Reynolds number on an impermeable plate.enReport