SpaceX’s Starship is the most powerful launch system ever built, dwarfing even the mighty Saturn V both in terms of mass and total thrust. The scale of the vehicle is such that concerns have been raised about the impact each launch of the megarocket may have on the local environment. Which is why a team from Brigham Young University measured the sound produced during Starship’s fifth test flight and compared it to other launch vehicles.
Published in JASA Express Letters, the paper explains the team’s methodology for measuring the sound of a Starship launch at distances ranging from 10 to 35 kilometers (6 to 22 miles). Interestingly, measurements were also made of the Super Heavy booster as it returned to the launch pad and was ultimately caught — which included several sonic booms as well as the sound of the engines during the landing maneuver.
The paper goes into considerable detail on how the sound produced Starship’s launch and recovery propagate, but the short version is that it’s just as incredibly loud as you’d imagine. Even at a distance of 10 km, the roar of the 33 Raptor engines at ignition came in at approximately 105 dBA — which the paper compares to a rock concert or chainsaw. Double that distance to 20 km, and the launch is still about as loud as a table saw. On the way back in, the sonic boom from the falling Super Heavy booster was enough to set off car alarms at 10 km from the launch pad, which the paper says comes out to a roughly 50% increase in loudness over the Concorde zooming by.
OK, so it’s loud. But how does it compare with other rockets? Running the numbers, the paper estimates that the noise produced during a Starship launch is at least ten times greater than that of the Falcon 9. Of course, this isn’t hugely surprising given the vastly different scales of the two vehicles. A somewhat closer comparison would be with the Space Launch System (SLS); the data indicates Starship is between four and six times as loud as NASA’s homegrown super heavy-lift rocket.
That last bit is probably the most surprising fact uncovered by this research. While Starship is the larger and more powerful of the two launch vehicles, the SLS is still putting out around half the total energy at liftoff. So shouldn’t Starship only be twice as loud? To try and explain this dependency, the paper points to an earlier study done by two of the same authors which compared the SLS with the Saturn V. In that paper, it was theorized that the arrangement of rocket nozzles on the bottom of the booster may play a part in the measured result.
“SpaceX’s Starship is the most powerful launch system ever built, dwarfing even the mighty Saturn V both in terms of mass and total thrust. ”
https://en.wikipedia.org/wiki/N1_(rocket)
http://www.astronautix.com/n/n1.html
“Starship is the world’s most powerful launch vehicle ever developed, capable of carrying up to 150 metric tonnes fully reusable and 250 metric tonnes expendable.”
“The N1 launch vehicle, developed by Russia in the 1960’s, was to be the Soviet Union’s counterpart to the Saturn V. [..] ”
“The third variant designed was a ‘Super Rocket’ with a lift-off mass of 2,000 metric tons and a payload of 150 metric tons. This was a true antecedent of the N1. [..]”
Four launches, four failures. The N1 doesn’t seem to have been a very useful launch system.
It may have been designed for a 150 ton payload, but it never achieved it.
It wasn’t designed for a 150 ton payload. That “Super Rocket” was a paper design that was thrown away before N1 development started, and depended on its second and third stages being nuclear powered. The N1 design, if it had ever flown without blowing up, was capable of 70-95 tons to LEO depending on which source you’re reading.
For the N-1, the Soviets didn’t build a test stand where they could test the first stage. Instead, they decided to do those tests by flying the rocket. They fully expected multiple launch failures. A similar approach was used for the Proton, which had 14 launch failures before its first successful flight.
The links and quotes provided indeed validate that statement. The N1 gets to be tied for third place, depending how you count it.
Think the write meant “Successfully launched”
Building the equivalent of a moving bomb is not the same thing at all. The Russian space program is successful despite their attempts. The N1 was never going to fly with the speed at which they rushed development and didn’t test. Aside for the Energia platform Russia has never succeeded in a launch vehicle that rivals what the US and now SpaceX have been able to achieve.
For a read about the Soviet Space program I suggest a book – The Wrong Stuff – How the Soviet Space Program crashed and burned – by John Strausbaugh.
So, like SpaceX, Russia fails to success?
The difference is SpaceX owns up to them. Russia swept a number of missions and designs into the “didn’t happen” category and until the country opened up after the fall of the wall in the 90s we knew almost nothing about their failures…only successes. Mind you, little difficult to claim the N1 didn’t fail when the detonation of the vehicle set off blast detectors hundreds of miles around.
No, with SpaceX it’s more “succeeds to success”. It’s rare to see an actual SpaceX failure. It’s more people that don’t understand the “failures” that claim they were failures. Imagine designing a new top speed record car to go 1229km/h and it ends up going 1335km/h and people say you failed because you went faster than you planned.
The N1 wasn’t a heavy lift rocket, it was a fireworks display.
You need at least one launch that doesn’t blow up on the launch pad to qualify as the most powerful rocket. Maybe it could get somewhere high in the running for most powerful non-nuclear explosive
Three out of the four flights of the N1 catastrophically failed far enough downrange to not destroy the paunch pad. One even made it a few seconds short of the full first stage burn.
Not that it matters for ranking the most powerful rocket. It was smaller than Starship/Super Heavy by every metric except diameter at the base. I really can’t figure out what Joshua’s point was.
Hey, circumference is a very underrated metric! Or at least that’s what I keep telling myself
I’m almost 16 miles from 39A here on the Florida coast. I think it’s time to get the house on the market.
Around 25 km, so according to the chart you would hear something a little quieter than a table saw maybe 25 times per year… How much? My neighbors are way worse than that
0.0000474% of the way to Mars! An un-survivable craft, on an un-survivable mission. Soon to be re-made of spruce.
Soon to be doing everything that NASA needs a heavy lift for because NASA can’t build launch vehicles anymore. The coping is pretty funny, just admit you have some variety of derangement syndrome. Just come out of the closet with it, it’ll feel great
NASA never built launch vehicles. They worked together with manufacturers to have them built.
NASA has never been a manufacturer.
well musk is the new howard hughes and the h-4 hercules did fly and starship did fly. stifling innovation is not the answer. why dont you make something and stop being jealous of the ones that do.
The H4 was in ground effect. Once. It never actually “flew”
Lets hope that Musk hasnt started canning his bodily waste and fluids yet.
My wife and I used to vacation at South Padre island. was a beautiful and quite place until musk came along.
Never went back after he started launching Roman Candles off the beach.
How frequent are the launches?
There has only been 4 launches this year.
I’d like to take a moment to point out that there are multiple, shadily funded, troll-like “environmental” groups that are verifiably funded by anti-spacex individuals. The implication being that this may be a paid, politically motived, post.
I am not saying it is, but there is a non zero chance this is a paid troll.
This.
I used to do the same when I was younger. I’m thinking of going specifically to watch one go up. I always felt sad that I wasn’t around to see the Saturn V launches, now I have another chance.
You people are so bitter by the way. We all know you’re not really mad at him for launching noisy rockets in the part of south Texas where you can’t even find a gas station for eighty miles.
this bitterness is one among many reasons the election was such a landslide. people are just sick of it. time to move on.
Your loss, I guess? Plenty of people now travel there to view the rocket launches.
No loss for me. I can care less about seeing a rocket launch. We now vacation in Jamaica :)
How frequent are the launches?
Just Florida, over 50 launches to date.
There have only been 4 launches in 2024 and 2 the previous year. They have only been from Boca Chica, Texas, and not from Florida.
SpaceX has built a launch tower for SuperHeavy/Starship at the pad 39A launch complex at Kennedy Space Center in Florida but it doesn’t have a launch mount yet. Nothing has been launched from it yet. Environmental study is underway for a seconf Florida pad to allow for a higher launch cadence once Starship is operational.
You may be thinking of the much smaller Falcon 9, which has launched 74 times so far this year in Florida from SpaceX’s pads 39A at Kennedy Space Center and Space Launch Complex 40 at the adjacent Cape Canaveral Space Force Station. The Falcon Heavy (heavy lift variant with 3 F9 first stage cores in parallel).
The FAA just moved forward with approval (not finalized, but on the way) for 25 launches a year from the Texas site.
meh. probably just the volume of a small secondary monitor setup for a Disaster Area concert…
get those peril sensitive sunglasses ready
Sooo let me get this straight. They found out the big rockets make big noise. Now that’s science.
Was any taxpayer money squandered that, PhDs “earned” ? The Feds made Musk kidnap seals, strap them to a board, put headphones on them, and play sonic booms to see they became distressed. Did they run a control group of seals kidnapped, strapped to board, headphone put on and play Kenny-G to measure the differential distress? You know what sounds a lot like sonic booms … thunder. Are seals distressed by thunder?
And how much of that grant money was spent “setting up” the listening station at Hotel Margaritaville?
Oh wait, the Mormon students of BYU don’t drink alcohol or Coca-Cola!
B^)
Yes they will continue to regulation-harrass him and whittle away at these businesses like resentful, bug-souled Randian villains until he agrees to sell them back their favorite propaganda network. It’s clear to anybody with eyes
Something wasn’t known. They measured it. Now it is known. Yes that is literally what science is.
You had two choices: you could look up what the paper did and why, or you can make up a fantasy and get all outraged about it. Sadly, you chose the second.
Noise is part of the environmental permits. Until now, they were using simulated data, which turned out to not be completely accurate. They are louder in some metrics, and less loud in others. Now they can make more accurate assessments, rather than winging it.
these environmental studies never really cover the costs of making a new rocket every time you go to space vs a reusable rocket. granted were not there yet, but musk’s method is a lot less wasteful than the nasa method. also nobody mentions tne environmental impact of bureaucracy, someone ought to do a study on that, also the effects of bureaucracy on mental health.
as a side note i always thought it was funny how quickly they got a launch license this time, i guess the bureaucrats dont want to be doged out of their cushy government jobs and rushed it along.
The environmental studies are not being done for the sake of the environment in this instance. It’s lawfare, standard tactics. No amount of debating the subtleties of how much waste is actually prevented will sway them, because they don’t care about that at all. Just mark them as cynical bad-faith actors and move on
Crossing the right palms with silver has always expedited things.
So, how loud would the sound be if something went wrong, and the Super Heavy has a super explosion? It would be comparable to Hiroshima. How would Brownsville TX fair in such a case?
Some years ago the there was research being done at the Naval Research Laboratory in D.C. on the effects of the sound and vibration of rocket exhaust on materials. IIRC the test chamber was about the size of a basketball court. The huge volume of gas needed was obtained by heating liquid nitrogen with a propane burner. The outside tank holding the liquid nitrogen required three tanker trucks to fill. I was told that if the power of the sound was turned up all the way the concrete walls of the chamber would de-laminate.
Brownsville would fare just fine. Its easternmost residential areas are about 25 km from the launch site, and “comparable to Hiroshima” is wrong in both magnitude and altitude.
Hiroshima was 15 kT and was detonated about 600 m above ground specifically to maximize damage; an explosion at ground level sends much more of its energy skyward and causes damage over a smaller area on the ground. A 1 kT (see below) surface burst at the launch site wouldn’t damage Brownsville at all. I couldn’t tell you how loud it would be; sound propagation across terrain is complicated and weather-dependent. I’d be curious if anybody has suitable software to run some simulations.
As for magnitude, the N1 provides a reasonable worst-case example at about 1 kiloton TNT equivalent. There was far more energy than that available in the propellants, but only the fraction of fuel and oxygen that mixes before ignition can participate in the detonation. That rocket impacted the ground intact, which caused significant pre-mixing and about 15% of its propellant was immediately combusted. The rest of the fuel still burned (mostly), but slowly enough to not contribute to the blast wave.
American rockets are required to have a flight termination system, less euphemistically known as a self-destruct system, to prevent that sort of thing. The FTS is designed to rip the propellant tanks open before the failing rocket hits the ground, allowing far less pre-mixing and reducing the violence of the resulting explosion. It’s notable that this is one area that SpaceX initially half-assed, and when the FTS was activated on the first flight of the Super Heavy/Starship stack, it failed to disassemble the rocket. The FAA was justifiably pissed about that and forced SpaceX to revise the system. Assuming they didn’t screw it up again — which is a reasonable assumption as the FAA was not yet owned by Musk — any failure would produce a blast much weaker than the N1 crash.
They do think about this sort of thing. Scenarios like this are the primary basis for determining the size of the exclusion zone around a launch site. The exclusion zone border gets within about 5 km of the pad for these launches.