FAR 91.200 section

[midlifeflyer]

I don't recall the number of the AC but I will get it artwork tomorrow.

It's AC 91-67 available at
www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/MainFrame?OpenFrameSet

This can be a very complex issue. I deal with it every day, and the AC has a good flow chart that encompasses all these scenarios.

Actually, I have a minor nit with the flowchart in the AC. It has you move from whether it is required by POH equipment list in turn to whether it is required by the Type Certificate for the airplane (if you can find it) to whether it's required by AD to whether it's required by 91.205 (or the other operational rules) to removing and placarding it if applicable.

Then, (3 hours later if you've managed to find the type certificate) the pilot decides if it's safe to fly without it.

I tend to start with whether I think it's safe to fly without it, regardless of whether it's technically legal or not, then to 91.205 etc (since it's the shortest list and most of us were =required= to memorize TOMATO FLAMES and FLAPS) before proceeding to the more detailed stuff.