Empty Fuel Tanks → Higher fuel consumption?

[Karon]

I'm making a simplified Fuel consumption model for my site, I'm particularly interested in the effect of weight and DI and how these factors affect the flight performance.

 

 

I started with a standard CAP loadout (4xAIM-54, 2xAIM-7, 2xAIM-9, 2xFT, Gun - CFG A), then I tried the same loadout but with empty bags (CFG C) and the results are unexpected. For the sake of testing, I copied the original loadout but reduced the amount of internal fuel (CFG D) to match the weight of the test with empty bags.

 

 

So, what's the issue here? Well, it looks like that the empty bags require a higher fuel flow to match the same performance. The last test instead is close to the original but requires a bit less juice to fly, due to the lower weight.

 

 

 

 

I didn't have time to double check some odd results, although quite a number of interesting things came out from these tests.

 

 

This is the loadout I tested. As you can see, nothing fancy: