Grayhawk,

 

I didn’t say there is never a good reason for placing fuel in the fuselage instead of the wing, I only suggested, as I said, that life is a series of tradeoffs.

 

As to your comment below, I may be misunderstanding your point, but it seems you are suggesting because the aircraft designer chose a fuel management system incorporating a header tank there is no additional stress on the spar by placing fuel weight in the fuselage instead of the wing. If that’s your position, I disagree.

 

Think of lifting a barbell using a strap on each end. If you place 200 lbs of weight on each end (400 lbs total), the bar will remain relatively straight when you lift it. Put that 400 lbs in the middle, however, and  the bar will most definitely flex.

 

Where the engine feeds from isn’t germane, it’s the location of the weight that matters. Your header tank places some 60 lbs of weight directly on the center of the spar (I realize its CG is forward of the spar, but the weight carried by the spar is at the spar’s center, not towards its ends). While the additional stress on the spar from that weight may indeed be within design limits, there can be no question there is additional stress.

 

--Mark