Custom format the flight time and running total cells as mentioned above i e [h]:mm ATD and ATA will be in hh:mm
If you want to subtract your ATA from ATD and these occur either side of midnight then you will have to set up a formula in cell C1
=IF(SIGN(A1-B1)=-1,A1-B1+1,A1-B1)
Where A1=ATD B1=ATA and C1 is the flight time
It will produce the correct answer if you fly in a day or over midnight Good luck
