What is the fuel mass flow rate at stationary full power for the CFM56 5C2/3C1 engines?
If you know the TSFC at conditions above I can calculate the fuel mass flow and would resolve the issue.
  


From this page, the CFM56-5C2 used on the A340-211/-311 delivers 31,200 lbf and its SFC is 0.320 lb/lbf hr. The cruise thrust and SFC are 6,910 and 0.545 respectively.