ACR WDB PRODUCES JET BLAST ENCOUNTER SIT FOR BAGGAGE CARTS DURING ENG START PROC.

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INCIDENT OCCURRED DURING TAXI IN ATL; WDB WEIGHING APPROX 402000 LBS ON SINGLE ENG TAXI. WHILE EXITING RAMP 1 S; EXECUTING 90 DEG R TURN ONTO PARALLEL TXWY; LOST MOMENTUM. IN PROCESS OF STARTING #1 ENG; THRUST FROM #2 WAS DIRECTED TOWARD BAGGAGE VEHICLES AT S END OF RAMP AND RPTEDLY BLEW AT LEAST 3 CONTAINERS OVER. THRUST WAS NORMAL FOR CROSS-BLEED START (70 PERCENT ON #2); BUT THE LONG TIME WAITING FOR #1 TO START AND COME UP TO IDLE CONTRIBUTED TO THE PROB. WE WERE STOPPED 45 DEGS INTO TURN AND IT TOOK AT LEAST 2-3 MINS TO GET ACFT ROLLING THROUGH TURN. FOR INFO; SINGLE ENG TAXI (WITH APU) IS AN AUTHORIZED PROC; AT CAPT'S DISCRETION. HOWEVER; THIS IS THE SECOND INCIDENT I HAVE WITNESSED IN THE PAST MONTH WHERE MOMENTUM WAS LOST IN A TURN OR SOFT SPOT DURING TAXI AND THE BREAKAWAY THRUST REQUIRED CAUSED PROBS. I THINK THE COMPANY'S PUSHING SINGLE ENG TAXI AS A COST SAVING MEASURE CONTRIBUTED TO THE PROB; THAT PERHAPS A MAX WT FOR SINGLE ENG TAXI SHOULD BE RECOMMENDED. SUPPLEMENTAL INFORMATION FROM ACN 249816: SHORT TAXI; STARTED #1 ENG PRIOR TO REACHING TXWY. NORMAL PWR TO TAXI ON #1 ENG IS 72-75 PERCENT N3. STARTING SECOND ENG REQUIRES PWR FROM OTHER ENG TO BE SET AT 70 PERCENT N3. THE ACFT WAS ROLLING; BUT AS WE WERE MAKING A R TURN ONTO TXWY (A SLIGHT RISE FROM RAMP TO TXWY); ACFT CAME TO A STOP AT 45 DEG ANGLE WAITING FOR #1 ENG TO COME ON SPD. WE SAT FOR A FEW MOMENTS; THEN #1 CAME ON SPD AND WE PROCEEDED TO RWY 9L. TIMING IS CRITICAL DURING TAXI. I COULD HAVE DONE 2 THINGS TO CORRECT THIS: 1) START 2 ENGS AT PUSHBACK OR; 2) USE THE APU FOR A CROSS-BLEED FROM THE #1 ENG SO I HAD MORE PWR FROM #2 TO KEEP THE ACFT MOVING WHILE MAKING THE TURN. SUPPLEMENTAL INFORMATION FROM ACN 249583: A CONTRIBUTING FACTOR TO THIS INCIDENT WAS THE PRESSURE FELT BY FLC TO CONSERVE FUEL AND TAXI ON REDUCED AMOUNT OF ENGS; AND THE FACT THAT ENG START IN THIS ACFT TYPE TAKES AN EXTENDED AMOUNT OF TIME.