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> Are people forgetting about how incredibly loud is a sonic boom? It is unlikely that it will get rights to fly over land, just like the Concorde.

Remember a few years back when the Canadian-made Bombardier C-Series was selling well, so Boeing got their allies in the US government to impose a 300% tax on them as an "America First" policy?

Well, the rules around sonic booms were similar. Were there sonic booms? Sure. But the real reason for the ban was that they were foreign-made sonic booms.

Now the world's only supersonic passenger plane is being made in America, you might find Congress is much less worried about sonic booms.

Sure, being a domestic enterprise might help here, but you will have to deal with regulations abroad, too (and Concorde had arguably the edge there because it had both London and continental Europe as home court).

I'm also fairly sure that softening/undermining noise regulations in general has become harder (less tech enthusiasm, more NIMBYism, especially in Europe).

This isn't true. The backlash to sonic booms grew well before Concorde and was part of why the US government canceled its support of the SST program. Boeing canceled their part of the 2707 because of the (extremely) unexpected success of the 747 program (a larger plane slower addressed a larger market) and the 737 success.

Sources:

Joe Sutter, Creating the worlds first Boeing Jumbo Jet

Thomas Petzinger, Hard Landing

>But the real reason for the ban was that they were foreign-made sonic booms.

You are wrong.

https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests

This was done to prepare people and gauge the reaction to BOEING sonic booms, for the SST. Everything about a supersonic future was scuttled when it became obvious that people clearly suffered when planes flew supersonic above them.

Keep in mind that the US Air Force still does not go supersonic over populated areas except when absolutely necessary, like during 9/11.

This study mind you was done with SCHEDULED sonic booms. Now imagine, instead of being able to set your clock to a loud, disruptive noise and plan around it, you must deal with completely unpredictable and variable EXPLOSION of sharp noise (130ish decibels is standing 100m from a jumbo jet as it spools up or a trumpet being blasted directly into your ear from a couple feet away)

People already hate the noise of cities when that noise is an occasional quiet siren heard from a mile away a few times a day. Imagine instead if the noise was completely unpredictable explosions. Also imagine you can't move out of the city to get away from it, because the sound blankets an entire flight corridor.

Unless NASA finds a way to magically evaporate all the energy in a sonic boom such that it makes almost no noise at ground level, we would have to literally depopulate mile wide corridors of the US just so a bunch of stupidly rich people can get from NY to LA in an hour? Nah

> Are people forgetting about how incredibly loud is a sonic boom?

Is it? I lived in Kansas in the 1960s. Sonic booms from the AF base were common. They weren't that loud. Electric storms (a regular in Kansas) were considerably louder.

> The Concorde burned fuel (passenger miles per liter) at roughly twice the rate of non-supersonic aeroplanes.

5-7 times as much.

My dad said when he pushed his jet supersonic, you could watch the gas gauge unwind.

Also, sonic booms are awesome. I don’t know that I want to hear them every 15 minutes, but they are cool.

> My dad said when he pushed his jet supersonic, you could watch the gas gauge unwind.

Did your dad fly military jets? Most older jets can't supercruise, i.e. go supersonic without using afterburners, and afterburners consume unholy amounts of fuel. Concorde did consume quite a lot of fuel per passenger mile, but it could supercruise.

Yup, military fighters.

The one new factor is the route fragmentation that occurred over the Atlantic with the 757 and 767 and the fragmentation that occurred over the Pacific with the 777 and 787. These changed from a model where only hub to hub flights where every seat had to be sold to be viable from a financial point of view to enabling many city pairs to work, and airlines still to make a profit, even if the business class seats are not fully sold. This led to a much larger market, which plenty of room for 3-10k "business class" tickets on these flights.

If boom can hit that same number, they will have success out of the USA <-> Europe market and premium intra-asia flights - the two most profitable route systems in the world.

You should write more about this on a blog or something, it's interesting and you seem knowledgeable.

They claim they have sonic boom solved by modifying the airframe shape. Otherwise, i agree with you. It will be a thing of no real consequence just like the original Concorde.

> Are people forgetting about how incredibly loud is a sonic boom?

One of the unique selling points of their proposed aircraft is that it won't be so loud:

> Boom says Overture will be a lot quieter than Concorde and the supersonic military aircraft that were flying at the time the FAA ban

https://www.freethink.com/energy/boom-supersonic-flight

That's a claim without evidence. A sonic boom is a direct outcome of moving through the air faster than the air can move through itself.

How have they demonstrated that they know how to cause quieter sonic booms?

Firstly, my claim that they say this is evidenced by the link. I did not assert it as historic fact that this thing works, just that this is what they say. The words "Selling point" and "proposed" are in that sentence for a reason: it's not actual yet. But if you think it's a deliberate fraud, then say so.

Secondly: Although the final proof of it is in the full scale aircraft for sure, a lot can be done with software modelling (1) and wind tunnels these days. And with the scale model that just flew, to be followed by "checking the actual performance that was demonstrated against what our models predicted, and how we expected it to fly." (2)

Thirdly, I point you to other "quieter supersonic" aircraft work in progress, the X-59. Some of their evidence-gathering process is detailed at the Wikipedia link, "development" section. (3)

It will be interesting to see how these work out; but if they do not, then it's a failure of modelling and design, not because they missed the directly obvious. But if you are an aerospace engineer and know more about this subfield, then say so.

1) "Boom has perfected its aircraft’s efficient, aerodynamic design using computational fluid dynamics, which “is basically a digital wind tunnel"."

https://edition.cnn.com/2025/01/28/travel/boom-supersonic-fi...

2) https://www.livescience.com/technology/engineering/boom-supe...

3) https://www.lockheedmartin.com/en-us/products/x-59-quiet-sup...

https://en.wikipedia.org/wiki/Lockheed_Martin_X-59_Quesst

A sonic boom is not necessary when moving faster than sound, the Busemann biplane resolves that completely.

There's been considerable work on sonic boom mitigation for many decades. Boom's long nose, flat underside, top engine, small wingspan delta wings are all designs expected to mitigate a sonic boom. Let's see if it works in practice.

Revisiting this, does this count as evidence? I see it as at least 1 data point

https://news.ycombinator.com/item?id=42999735

https://boomsupersonic.com/boomless-cruise

> Concorde flew NYC<->LON in 3.5 hours. I guess Boom will fly the route in about 4 hours.

I feel that you're getting diminishing returns at the point of reducing 4 hours to 3h30, given that flight time is just a part of the whole "door to door" time, there are several hours at least that aren't flight time, and that the expensive tickets all come with an hour or three in an airport lounge.

I think the real advantage would be for transpacific flights. San Francisco to Tokyo is currently about 11.5 hours, assuming a similar ratio (maybe slightly better due to flying supersonic for longer), Boom’s time would be around 6.5 to 7 hours. Savings would be more significant for East Coast flights, ATL-HND would go from 14.5 hours to under 8.5.

East Coast US to Japan supersonic? This is the stuff of fantasy. With the insanely high fuel burn and very small aeroplane body size, where are you going to put all the fuel for a trans-Pacific flight? NYC<->LON was already nearly the limit for the Concorde. As I understand, they had high priority when landing due to low fuel.

Interesting, I hadn’t realized the range was so short. I guess if they did trans-Pacific it would mostly be limited to Seattle to Tokyo, or routes with a stopover in Hawaii.