I roughed out some numbers for the comparison using a 12% allowance for the air density,BSFC 0.537,and R-R from the Caterpillar article based upon the test weights and given speed.
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*The naked F-150/Apex combination comes in at Cd 0.600 for the rig,based upon the frontal area of APEX.
* Drag factor of 37.2 sq-ft.
*The EcoBoost behaves as if the F-150 has Cd 1.03.
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*The F-150 Aerolid-RV/APEX combination is Cd 0.506.
*Drag factor of 31.372-sq-ft.
*The EcoBoost behaves as if the F-150 is Cd 0.87.
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*The Aerolid-RV setup provides a 15.6% CdA reduction.
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Going after the vertical edges of APEX,it's gap,rooftop AC unit, tail,and maybe the belly, should line 3-Cherries up for a big jackpot at the gas pump.