AN EMB145 EXCEEDED MAX RAMP WT.

Narrative

REGULAR SCHEDULED PART 121 FLT FROM ZZZ1 TO ZZZ2 WAS 30 MINS BEHIND SCHEDULE; WHEN BAGGAGE AND PAX WERE BOARDED. THE ACFT TO BE FLOWN WAS AN EMBRAER 145MP MODEL; WHICH DIFFERS FROM THE COMPANY'S COMMON 145LR ACFT IN MAX RAMP WT AND MAX TKOF WT. MAX LNDG WT AND MAX ZERO FUEL WT ARE THE SAME BTWN LR AND MP MODELS. 145LR: MAX RAMP WT = 48722 LBS; MAX TKOF WT = 48502 LBS. 145MP: MAX RAMP WT = 46495 LBS; MAX TKOF WT = 46275 LBS. WHEN ACFT WAS BOARDED; IT WAS NOTED ON LOAD RPT THAT WT OF ACFT WAS 467 LBS OVER MAX TKOF WT AND DECISION WAS MADE TO BURN EXCESSIVE FUEL ON THE RUN-UP PAD BEFORE TKOF IN ORDER TO BE MAX TKOF WT COMPLIANT. DURING BURN-OFF; IT WAS NOTED BY BOTH CAPT AND FO THAT ACFT HAD LEFT THE GATE 247 LBS OVER MAX RAMP WT. BY THE TIME THE OCCURRENCE WAS NOTED; THE ACFT'S WT WAS ALREADY BELOW MAR RAMP WT AND DECISION WAS MADE TO BURN THE REMAINING FUEL OFF IN ORDER TO BE BELOW MAX TKOF WT AND DEPART DCA FOR SDF. FLT LEFT WITH ABOVE MINIMUM FUEL. CONTRIBUTING FACTORS: 1) 30 MINS BEHIND SCHEDULE. 2) DIFFERENT TKOF DATA (MAX TKOF WT AND MAX RAMP WT) FOR MODEL FLOWN COMPARED TO COMMON ACFT FOR AIRLINE. 3) CAPT AND FO WERE FIXATED ON BEING MAX TKOF WT COMPLIANT; ACCIDENTALLY DISREGARDING MAX RAMP WT. PREVENTIVE MEASURES: 1) CAREFUL HANDLING NUMBERS ON NON COMMON ACFT. 2) DOUBLECHK NUMBERS ON LOAD RPT. 3) DO NOT LET SCHEDULE PRESSURE YOU OVERLOOKING ITEMS.