A tractor-trailer doing 55 mph shoved aside 18 tons of air every single mile. Half the engine's power wasn't moving freight—it's just pushing air out of the way. That's fuel burning for nothing.
NASA engineers grabbed a beat-up Ford van from the motor pool and turned it into a test rig. They built a square aluminum box around it and started rounding off edges, sealing the bottom, measuring everything. Just rounding the front edges cut drag by 52%. Sealing up the underside saved another 7%.
Then they got serious. They leased a cab-over and went to work. Rounded the corners on the cab, barely lost any space inside, dropped drag by 40%. Rounded everything they could, lost 3% of interior room, cut drag by 54%. But the big win was closing up that gap between the tractor and trailer. That alone saved 20 to 25% on fuel. An owner-operator running 100,000 miles a year? That's 7,000 gallons staying in the tank.
So, yeah, aerodynamics, but why the hell was NASA wasting tax payer dollars on trucking? Was it because they'd put man on the moon and didn't have a damn clue what to do next to keep the budget numbers for the next fiscal budget year? I'm pretty sure NASA didn't accomplish a damn thing for a decade, until they got the shuttle flying, just to put satellites into space. Not that that was much changed from the rocket era, which had already perfected accomplished satellite placement. And now? Space X is 90% cheaper at doing the same job.
