I have personally encountered difficulties in grounding and bonding when different portions of a distributed instrumentation system used "local" grounds on the

I have personally encountered difficulties in grounding and bonding when different portions of a distributed instrumentation system used "local" grounds on the nearest aircraft structural member as their ground reference. The ground potential from one place to another on the structure of an aircraft in flight can vary wildly. This caused no end of problems (sudden shifts in parameters, dead power supplies, etc). For performance critical applications, minimize the number of grounds.