FLT CREW PRESENTS AN EXAMPLE OF HOW FLEET INCONSISTENCY SLOWS UP DECISIONS AND COMPUTATIONS NECESSARY FOR COMPLIANCE WITH ATC CLRNC.

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INSTRUCTED TO CROSS FREDI AT 10000' MSL. AFTER DSCNT WAS INITIATED DECISION WAS MADE TO USE FLT SPOILERS TO ACHIEVE MAX RATE OF DSCNT DUE TO LATE REALIZATION OF APPARENT CHANGE IN WIND. APPROX 5500 FPM REQUIRED TO MAKE RESTRICTION. ALTHOUGH RESTRICTION WAS MET; R.O.D. WAS EXCESSIVE AND APPARENTLY MSP ARTCC'S ALT READOUT DID NOT KEEP UP WITH OUR DSCNT. CONSEQUENTLY; THE CTLR WAS FORCED TO INQUIRE AS TO OUR ACTUAL ALT AS WE PROCEEDED INSIDE THE FIX. HE WAS ADVISED THAT IT WAS INDEED 10000' AND WE WERE TOLD TO CONTACT MSP TRACON. OUR AIRLINE UTILIZES AT LEAST 4 DIFFERENT COCKPIT DISPLAYS IN ITS MLG ACFT. ALL HAVE THE DME READOUT IN DIFFERENT LOCATIONS. IN THE ACFT WE FLEW THIS DAY DME INFO REPLACED COURSE INFO NORMALLY DISPLAYED IN THE SAME PLACE IN OTHER COCKPIT TYPES. CONFUSION ASSOCIATED WITH THIS INCONGRUITY CAUSED DELAY IN THE FLYING PLT'S REALIZATION THAT HIS INITIAL RATE OF DSCNT WOULD BE INADEQUATE TO MAKE THE ASSIGNED XING RESTRICTION. CONSEQUENTLY; A MORE EXTREME R.O.D. WAS REQUIRED; MORE THAN WHAT WOULD HAVE BEEN NEEDED IF THE SITUATION COULD HAVE BEEN DETECTED; INTERPRETED EARLIER. COCKPIT'S INFO SYS MUST BE STANDARDIZED BY REG.