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One example is the effective prohibition on spraying pesticides by air, including drone. Drones allow lower pesticide use than current, legal practices

On a typical day, the atmospheric pressure varies by maybe 150 Pa, or 3 psf. By definition, that’s 137 dB. But it’s imperceptible because the rate of change is so low.

It’s not accurate to convert .1 psf to dB because it’s an impulsive shape, not a continuous tone. And human loudness perception depends on how smooth (low frequency) the shape is

One slight advantage: you can store liquid nitrogen. So, you can use cheaper electricity to produce it

The engine load is probably a steady, consistent magnitude. While a landing load is rapid and variable. Also, you need to design legs for wind loading after landing, which can be high if you want to launch often.

or its shiny because vacuum hardware is routinely electropolished?

I think the original plan was to convert the heat back into electricity with a turbine. So the higher temperature of sand would greatly improve thermodynamic efficiency.

Yes a storm could damage the coal plant with some small probability. But now you have replaced the coal plant with batteries + solar. Solar will be disabled by every large storm due to cloud cover. The grid will certainly be less reliable.

Pilots still fight turbulence today, usually by changing altitude. If this system allows the plane to stay at optimal (but turbulent) altitude, it could save fuel.

Stainless steel has its own safety issues (hexavalent chromium exposure from welding or grinding)

Private car insurance companies are pretty sophisticated, so they certainly know if a certain vehicle is causing higher claims and will price accordingly.

But, IMHO, the legal minimum liability insurance policy is way too low. A serious car accident could easily cause millions in personal injury damage. Most US states require only ~$50k personal injury coverage.

It's not just a passive payload, these targets have radio transmitters. So the task is probably easier.

In theory, a faster airplane is more productive (fly passengers farther in the same amount of time). So crew and capex costs are lower per mile. Maybe a crew can fly New York-London and then fly back, vs a subsonic airliner with a crew that flies one way, stays a day for crew rest, then flies back.

There are many in CA that are ridiculous. Most are not related to safety, but likely due to lobbying from some industry.

Fire sprinklers are required in single family homes. The very small incremental safety benefit is far outweighed by the initial cost, maintenance cost, and potential failures (more plumbing to leak). If you really wanted to improve fire safety, make it cheaper to replace 1950s-era houses with new construction!

Solar panels are required for new homes, which ironically adds a small amount of fire risk (like all electrical devices). This is required in areas with cloudy conditions, or houses that are shaded by trees. The cost per watt is ridiculous compared to how cost-efficient utility scale solar has become. Not to mention the safety risk to solar workers on a second-story house.

Just in plumbing code, there are several ridiculous restrictions. Some jurisdictions allow air admittance valves, others do not at all. ABS pipe is illegal for commercial buildings, but just fine for residential. IPC allows 1.5" vents for toilets, but UPC requires 2".