It's just directing airflow. This is a matter of definition. In the airplane industry, we define blown flaps as flaps getting air from a power source other than the airstream: from engine bleed air in the case of the F-4. We'd call Wes's system "slotted flaps". Here's a piece on slotted flaps: http://cafefoundation.org/v2/pdf_tech/High.Lift/Elsevier.Prog.AS.HighLift.vDam.02.pdf . On the scale of misuse of technical terms by the stunt community, this is a very minor offense.
What advantage do these style flaps offer? They seem rather complicated to execute.Thanks in advance.Happy New Year.Chris