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Comment by NegativeLatency | Hacker News Reader

I didn't see any mention of how this would impact overall noise levels. Is there some regulatory process being added to handle supersonic passenger aircraft?

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That's probably because changing fuel consumption goals has absolutely nothing to do with the magnitude or propagation characteristics of an atmospheric shockwave.

Unless the shockwave's shape (distorting coarseness of the wave front to soften the impact of sound waves; think: tweaking the volume knob to fade-in/fade-out a noise floor with gradual easing, rather than slamming a door as hard as you can) or size (how much air gets pushed around, overall) is altered by how a moving body breaks the sound barrier, a sonic boom will still be loud, and reach just as far.

When you crack a whip, the sound is just as loud, no matter how much energy your arm expends making the motion.

FTA "Additionally, the Lee-Gardner Amendment would require the FAA to eliminate the Mach 1 speed limit over the United States and replace it with a well tailored sonic boom standard."

Can somebody explain this please?

At super sonic speeds the noise is awful so to make it simple the FAA just says "no super sonic flight".

This changes that to force the FAA to do the complicated thing and be like "okay in these locations at this altitude and this size plane" and "at these locations at these altitudes and that size plane" and maybe "never at this location" or maybe "only during local business hours " and we end up with a book of "well tailored" regulations. Which while complicated might at least allow for Boom to operate inside the US, which opens up a lot business.

This is perhaps a bad political environment to propose a bill that would let billionaires operate supersonic pleasure craft over the US, at considerable annoyance to 99.99% of the population.

This seems like exactly the political environment to let the rich do whatever they want

For example, an SF - NY flight could be allowed to boom over northern Nevada, much of which is completely uninhabited. Right now it's completely forbidden over US territory.

> The Lee-Gardner Amendment would help us reduce drag by allowing us to make our engines narrower. Current engine noise rules for new supersonic aircraft are more stringent than those for the existing subsonic fleet. By setting our engine noise to the same levels as existing subsonic airplanes, we could make our engines produce so much less drag that we would save 20–40 percent on fuel, depending on whether you use this year’s or next year’s rules as a baseline.

They're narrowing the engine to get less drag and setting the noise to the same levels as conventional planes.

Skeptical. I know what narrower means but noise is a result rather than a parameter.

Engine noise is understood well enough that you can choose the level you want and develop an engine that is as good as possible that reaches that level.

It isn't the engine noise that is creating the sonic boom.

From my vague reminder about this the noise was widly exaggerated and booms design had a few things to make it slightly quieter.

Sonic booms are very loud and disruptive. NASA has done some research into mitigation by using blunt-nosed aircraft, but none of that applies to Boom's more conventional design.

Here's what the Concorde sounded like at altitude, from the ground: https://www.youtube.com/watch?v=cbPh2llw0-M

Being regularly subjected to anything even half as loud as that would be a complete non-starter for me.

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