Merlin IV A
Air Traffic Control Fully Certified
Confusion; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict
General None Reported / Taken
Human Factors; Procedure
I had a complex situation developing with the sequencing of the Air Carrier Y [aircraft] ([small piston aircraft] mostly) and an A319 with winds at 40 KTS out of the south. I had an Air Carrier Y going straight to approach end of 12L that I had to coordinate with Tower and then put the A319 in behind him and in front of Air Carrier Y1. I had Air Carrier Y2 as my #4 aircraft following Air Carrier Y1. I did not realize that Air Carrier Y2 was one of the few SW4's that fly into MSP. I created an unintentional overtake especially because Air Carrier Y1 was headed into the wind. We recently had an airspace/procedure change where the 'turboprops' now come in at a lower altitude and mix with the [piston] Air Carrier Y's. The old procedures when they came to me at 7;000 FT; was a helpful clue indicating it was a turboprop Air Carrier Y and not a [piston aircraft] that comes to us at 4;000 FT. Go back to putting the turboprops at the higher altitudes not mixing them with the slow props.
M98 Controller failed to note the type aircraft involved when establishing the final approach sequence; resulting in an overtake situation. The reporter listing a recent procedural change as contributing factor.