Ops Normal
Using the 'crews per airframe' equation is fraught with pitfalls if you are using it as a definitive planning option. The number of crews you need is driven more by the number of crews that are required to operate that airframe on a daily basis. If the aircraft is doing 2 sectors a day then you are going to need less crews than if it's doing 8-10 sectors. An obvious statement I know but one that is very easily overlooked by the bean counters! For basic high level numbers we work on 7 crews per airframe for shorthaul, 8.5 crews for mix long/short haul and 10 crews per airframe for long haul flying. However, these numbers are refined once the flying programme is known and can go up or down.
You also have the 'critical mass' equation to add in, that is the more aircraft in one base you have then the less crew you need per airframe, reducing at approx 1/2 crew per aircraft up to 4. As a basic calculation we use the following:
1 short-haul airframe = 7 crews per aircraft
2 short-haul airframe = 6.5 " "
3 short-haul airframe = 6 " "
4 short-haul airframe = 5.5 " "
For 5 airframes use the values for 4 + 1 above, for 6 use 4 + 2, etc.
I must stress however that these calculations are for high level numbers only and should be re-evaluated using the planned flying program. And don't forget to add in attrition, long-term sickness, training, etc.
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