Yes, seperate accelerometers are usually the FDR accelerometers and are also used for Aircraft Condition Monitoring Systems (ACMS). All sorts of data can be accessed if you know the right codes, ask an Avionics engineer.
Swedish - I don't wish to sound pedantic, but surely you mean IRS on a 737-400 and a B777. Totally different innards, although the outputs are almost the same I admit.
