ZFW and Center Tanks

[Minuteman]

I got to wondering about the Maximum Zero Fuel Weight (MZFW) Limit most manufacturers have for their aircraft. Its usually defined as something like, "the maximum weight allowed before usable fuel is included."

So lets say I have an aircraft with a big center fuel tank. Did the manufacturer set the MZFW limit to be as low as possible by subtracting a full center tank fuel weight from the design max. structural load?

For example, lets say there is an aircraft with a 14,000lb center tank, but it's making a short hop to its destination and needs only the fuel in the wings. The plane is already already at MZFW with more payload sitting on the ramp. Is the operator stuck flying around with an additional 14,000lb of unused capacity? I.e., is that how MZFW works?

 

[Baronman]

If the guy is at Max ZFW then it doesn't really matter how much more fuel he puts on (or takes off). Sure he could fill up the tanks but that's not likely given today's fuel costs. In your example it appears that he'll be leaving that cargo on the ramp for a later flight.

 

[B767Driver]

For example, lets say there is an aircraft with a 14,000lb center tank, but it's making a short hop to its destination and needs only the fuel in the wings. The plane is already already at MZFW with more payload sitting on the ramp. Is the operator stuck flying around with an additional 14,000lb of unused capacity? I.e., is that how MZFW works?

Yep, that's how it works. All weight above MZFW must be fuel.

 

[Minuteman]

Cool, thanks. I figure with a name like Maximum Zero Fuel Weight is should be pretty straight forward.