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Comment by 3D30497420 | Hacker News Reader

Apparently non-retractable door handles have only a very minor impact on drag/efficiency: https://arstechnica.com/cars/2025/09/flush-door-handles-are-...

So, yes, I think you're right that they are largely just a gimmick.

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If manufacturers in general were serious about improving efficiency they'd stop putting huge heavy wheels on everything, instead of chasing fractions of a percent with overcomplicated and failure-prone door handles.

Side bonus, smaller wheels with taller sidewall tires are more comfortable, less prone to damage, and the tires are cheaper and easier to replace, too!

Alloy wheels are pretty light, and the weight mostly affects acceleration.

At speed, most of your power is going to fight drag, so aerodynamics make a much bigger difference in efficiency.

Agreed. Plus the choices were never electrically actuated Vs. standard, plenty of vehicles before Tesla had flush fully mechanical doorhandles that reduced the drag coefficient.

Tesla did it to be different, futuristic, and to show off. Then plenty of other electric vehicle manufacturers copied. Even ignoring the safety issues, these things had reliability problems since almost inception and could be frozen shut in the winter.

Between the door handles, removing the turn signal stalk, removing the wiper stalk, non-round non-drive-by-wire wheel, and now putting the shifter in the ceiling, Tesla has made a lot of unforced errors to try to stand out.

> now putting the shifter in the ceiling

They what?! And people are still buying these things? This is the most valuable automaker in the world?

their profits are pretty normal, the stock is clearly more stock in musk himself than in the car company

Because you don't need to use that shifter regularly; you shift gears on the screen in that car and they have capacitive buttons near the caution lights on the ceiling as a redundant backup.

> you shift gears on the screen in that car

You're not helping bro. I'm literally crying right now what even is this car?

Musk has stated in various ways on different occasions that all driver input is error.

When that frames how you imagine drivers of your vehicles interfacing with them, all sorts of stupid shit starts looking like a good idea.

If you're driving in a competitive, sanctioned high-speed race, sure, fine. Save every bit of drag possible. At highway speeds in a normal-person shaped vehicle, they cannot possibly make a measurable difference.

Wouldn't that depend on the accuracy of the tool doing the measuring?

Not really. Stand in front of a car, squint, and observe the size of its silhouette. Now move slightly so that you can see the outline of the door handle, and consider its relative size compared to the rest of the car.

This isn't a perfect comparison. You could design car handles that look like little parachutes attached to something with the drag profile of a dolphin, but that's not a likely situation. In general, the area of the rest of the car is going to be many thousands of times that of the door handle. Given the difficulties in measuring, let alone modeling, turbulent air flow, it would be hard to detect a door handle's drag compared to the rest of the car.

I guess you could attach a meter to the door handle itself to detect how much drag it experiences from its own perspective, and that'd be pretty accurate. My hunch is it'd be an insignificant rounding error compared to the rest of the system.

It's not solely about size, it's about disruption of laminar flow which causes much more drag than the parasitic drag if the handle alone.

For sure, and hence the "little parachutes" bit. But most door handles are pretty streamlined compared to wheel wells, the wheels themselves, and decorative curves on normal vehicles built for routine transport instead of racing.

Top-trim Ioniq 5 has flush door handles for aerodynamic efficiency. Which is more than cancelled out by the stupid 20-inch wheels. Flush door handles are the pop-up headlights of this decade: questionable aerodynamic benefit, reliability issues, and let's be honest, only done to look cool.

(Granted, they're damned nice wheels. When people compliment the car in a parking lot, they usually talk about the wheels.)

Nissan GT-R manual flush handles.

https://www.youtube.com/watch?v=UK0MxfPE4N0&pp=ygUWbmlzc2FuI...

Honestly that's just as stupid. It would have similar problems in Winter, very little benefit, and has the same "How do you do it" problem

It however has no problem in the winter.

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