AussieBob
Do you do it on purpose boy?
C90 is different to C-90
B200 is different to O-200
Unless you are a Fly Baby aficionado and want to read pages of Harry Fenton's articles on fly baby.com (or fly baby.org, or pietenpol.whatever) I think we are talking -21's here.
Happy to be corrected if wrong.
This may help:
https://www.conklindd.com/t-turbopropvariablecost.aspx
Cheers Harry, catch up at OSH next year for beers maybe.
HD