I was reading part 91 studing up for any possible interview I might get and have this question. What is the maximum operating speed within class C airspace? I always thought 200kts however part 91.117(b) says:"Unless othersie authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4nm of the primary airport of a Class C or Class D airspace......"

So if I'm at 3k agl but in class C i can still kick 250kts?

I would think that you'd be fine, since you are above 2500 agl. That's why I love the FAR's, they leave no grey areas what so ever.

Yup that's quite okay. Just abide by the 250 knot below 10000' rule outside of that area...

Use that reg verbatim...200 kts within the 4nm x 2500 foot area, otherwise 250 kts, even within class C (unless you are under bravo airspace of course)

Class D airspace is normally, but not always 4nm x 2500', so normally 200 kts is the limit there. There are a few (such as KSEE) where the ceiling of the airspace is less than 2500 AGL, but you are still restricted to 200 kts if above the airspace but below 2500 AGL.

Class C is normally larger than 4nm x 2500' so you can usually go 250 kts within that part of the class C that is outside of the 4nm x 2500' area.

Or you will eventually rarely pull out a chart because you visit the same sh!t holes all the time and not even notice the class of airspace you are in. If you happen to be flying a prop, odds are you will always keep it at 250 until short final and then slow down continuously until the flare. If in a jet, well that will require configuring earlier so you might actually be slowed down prior to entering such airspaces as class D.

In jet operations, this usually has no effect on arrivals but on departures you have to remember to stay at or below 200 until >2500 AGL at smaller airports.

Actually what gets people in trouble is going 250 under the bravo when departing a class C/D airport. Especially in SOCAL.