John and Zeke,
I am truly enlightened (and entertained) on both of your comments regarding the VG's on the 717.
Is it possible that the nacell fins on the engine of the 717 are there (perhaps in addition to the reasons you have explained) to act in a similar way to which winglets or wing fences work. In that they reduce the amount of induced drag by restricting the span wise flow and therefore creating smaller vortices at the wing tip (in this case aft of the nacell). If this was possible, could that change the characteristics of the airflow over the lower portion of the fin/rudder, perhaps leading to improved controllability during single engine ops, especially at high AoA's?? I am guessing that there would be little influence from the nacell over the fin normally due to the jet efflux???
Another thought (driven by ignorance) The Beech 1900 and the Lear 60 (I think) have large ventral fins. Assuming they act in a similar aerodynamic way to each other, is it possible the 717 nacell fins are there for a similar reason?
I would appreciate your comments as I am merely a pilot with an interest for things I do not understand. i.e. Aerodynamics!!!
John, Yes I am pleased at the ACCC's decision. Your presumption is correct.
Cheers