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What's the difference between FMS (Flight management System), and FMC (Flight management computer)?

Can the flight management computer be thought of as what's manipulating the input information from the performance/navigation databases, and the FMS as being what actually provides the information?

I understand the information that's involved with the system, I'm just trying to define the difference based off an analogy of sorts.

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SKYbrary

Its definition is that the FMC is part of the FMS:

An FMS comprises four main components:

  • The Flight Management Computer (FMC)
  • The Automatic Flight Control or Automatic Flight Guidance System (AFCS or AFGS)
  • The Aircraft Navigation System
  • An Electronic Flight Instrument System (EFIS) or equivalent electromechanical instrumentation.

The FMC is a computer system that uses a large data base to allow routes to be pre-programmed and fed into the system by means of a data loader [...]

Putting that as a diagram plus the typical inputs and outputs:

diagram 1
— Own work

NASA

Since the inception of the FMS, it's been the same:

diagram 2
— CREEDON, J. "Flight management systems-What are they and why are they being developed?." Guidance and Control Conference. 1973.

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    $\begingroup$ Typically, the CDU's (or MCDU's) are considered part of the FMS as well. $\endgroup$
    – Ralph J
    May 23 '19 at 22:12

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