Ua 1093
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A United Airlines flight was hit by a weather balloon, prompting an investigation and discussion on the risks and regulations surrounding high-altitude balloons. The incident highlights the complexities of airspace management and the need for better tracking and safety measures.
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Oct 21, 2025 at 10:11 AM EDT
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Curious too to learn more about what data, if any, is shared with ATC on the location of these balloons. Airspace is regularly blocked off for rockets and other use, but for many weather balloons the theory is 1) the sky is big, and 2) designs are meant to be that a strike with an aircraft wouldn’t cause significant damage. If this was an impact with a balloon payload then “2” looks problematic.
The classic scenario involves birthdays, a one-dimensional space that closes in itself; while this one is a three-dimensional space that is closed on two of them.
Airborne objects also move so I don't know if that decreases or increases the probability of collisions, I guess it depends on how much correlation there is between their movements.
It sounds like a fascinating thing to study!
At any particular and above a certain flight level maybe.
Much more complex than simply amount of space times size of objects. Knowing theres a whole science / engineering behind this, Im just so curious about the people and practices that go into this part of travel especially air and space travel.
I'd rather be in a plane hit by 1 gram piece of space debris than in one that hit a 1kg sandbag hanging from a balloon.
This seems close to a worst case scenario for this failure mode, and everyone is still OK. I consider that good engineering.
And yes, this is good engineering, but through decades of learning crowdfunded with tax dollars.
You can argue that is not effective enough perhaps, but the mechanism itself exists.
An agency can remove a regulation it created. Congress (via the linked law) can also remove a regulation. Congress can also create regulations via legislation (though they typically don't go to that level of detail).
And we have to remember, at one point, every regulation that exists was created to solve a problem / prevent a harm. The cost of removing that regulation prematurely is reintroducing that problem / harm.
A good example is the state franchise laws against car manufacturers owning dealerships. Why can't Toyota sell me a car directly? Direct manufacturer sales seem to work fine in other contexts (e.g. Ikea). In Europe they're moving more and more direct sales. There's no good reason to keep them here in the US, but the dealership owners who benefit from these laws are the only people impacted directly enough to bother hiring lobbyists.
It would be comforting to believe so, but that requires ignoring every aspect of human nature.
Half the legislature campaigns on not doing anything if they get elected, though, and when they get elected, you get... Well, you get a lot of different things, most of them awful.
It's building on quicksand, but it's certainly not unprecedented.
In addition to the sibling comment's mention of the Congressional Review Act for agency oversight, there is a US Office of the Law Revision Counsel [2]. It has an official website [3] which is beautifully old-fashioned, but looks to be purely a resource for accessing the letter of the law and doesn't recount its volume of repeals in the same way.
None of this matters if the insane or counterproductive regulations are deliberate and desirable for the current lawmakers, of course.
[0] https://en.wikipedia.org/wiki/Law_commission [1] https://lawcom.gov.uk/repeals/ [2] https://en.wikipedia.org/wiki/Office_of_the_Law_Revision_Cou... [3] https://uscode.house.gov/
Government regulators have failed, but at least the company is making an effort to prevent this from happening again.
Once pilot got some light shrapnel and the airplane successfully landed with zero deaths. This is such a rare collision that people attributed it to SPACE DEBRIS initially.
The only fix I'd like to see the government make is allowing lightweight objects to broadcast transponder data. Even if they don't do that, another 50 years will probably pass before the next collision of this type.
Will air travel become safer because we don't know where they are?
1. See § 87.107: https://www.govinfo.gov/content/pkg/CFR-2024-title47-vol5/pd...
There are ADS-B transmitters that weigh 50 grams and would require 60 grams of batteries to power them for 8 hours, so payload limitations are not an issue for WindBorne.[1]
The CEO of WindBorne replied to a comment about the inability to use ADS-B on weather balloons saying, "Yea, the FAA does a lot and I think overall they do a great job, but I wish there was better systems for communications here."[2] So I'm reasonably confident that my understanding is correct.
1. https://news.ycombinator.com/item?id=45660400
2. https://news.ycombinator.com/item?id=45660577
1. https://uavionix.com/wp-content/uploads/dlm_uploads/2025/07/...
It's much, much lighter than a radar reflector, which aircraft weather radar displays aren't even designed to display.
Also for larger balloons, any trailing antenna must break if subjected to an impact force of 50lbs, or the antenna must have colored streamers every 50ft.
The ideal measurement would be some sort of crash testing. eg: The payload is accelerated at some standard velocity towards some standard target that represents the weakest part of an airplane (either cockpit glass or leading edge of a wing) and must not damage the target beyond some threshold. But that seems like it would be expensive, since every change in payload would require re-testing. Limits on sectional density seem like a good compromise.
1. https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F...
But still, in light of this I think we can do better. I think it's possible to operate the way we do and have a the mass distributed such that the only damage is ever cosmetic. We follow FAA 101 regulations on this but I want to have better internal impact modeling as well.
If that means that either you can’t release balloons or the aircraft can’t fly, then that’s a discussion that we should have about which we value more.
When I buy a ticket to fly on a aircraft, I do not want to know that I’ll probably survive if my plane hits a weather balloon, I want to know that my plane won’t hit a weather balloon.
I understand there are all sorts of inherent risks in aviation, and that if I want to fly, I must accept those risks. But hitting a balloon is not an inherent risk of flying, it’s a risk imposed on by others.
https://www.redbull.com/int-en/vincent-reffet-and-yves-rossy...
Somehow that rings some faint bell but can't quite put my finger on it...
WindBorne claims "12+ days typical flight, with demonstrated capability for 75+ day missions." So 1150Wh minimum (80Ah at 4S, which is probably like 16lb.) But you're up in the atmosphere and probably need to heat that battery so... more. But we're already at 18lb additional weight... Maybe you could offset with solar panels...
But, given that the entire balloon and payload weighs 2.5lb we're already way off the edge of feasibility for an active ads-b out.
Maybe there's something that would only listen and then respond when it heard something and that would reduce the power draw. But we're needing something 2 orders of magnitude less massive.
[1] https://uavionix.com/general-aviation/echoesx/
I obviously don't know which is right, but it does show that there is definitely confusion out there about the issue.
ADS-B out is still relatively new (especially in aviation terms) so I expect we'll see this continue to evolve.
[1] https://www.westmarine.com/plastimo-tubular-radar-reflector-...
A radar reflector such as that, or this (https://overlookhorizon.com/product/radar-reflector/, which is ~300g) has roughly the same RCS as a small (piper cherokee) to medium (gulfstream) sized aircraft.
That being said, detection isn't everything; primary radar cannot make accurate altitude measurements, only bearing and range. While that's enough to route traffic around, it could be also mistaken for a false return.
Project Loon balloons also show up on Flightaware, so they either have ADS-B or TIS-B.
A situation like this will almost certainly cause some congresspeople to fret and write bills that would require ADS-B on all balloons, which would be a death knell for amateur ballooning unless ADS-B (or "legacy" Mode A/C/S) transponders become significantly smaller and more affordable. Mode C/S transponders are already available in miniaturized form factors thanks to the UAS industry, and are designed to be interrogated by aircraft equipped with TCAS (i.e. all 10+ passenger aircraft) that provides pilots deconfliction commands automatically and with no ATC support. But they're still priced for industry, not amateurs.
[0] https://www.eoss.org/ Look for N991SS, N992SS, N461SG.
At this point, I'm pretty confident that NOTAMs exist as a way relegate all liability to pilots. Really it's 14 CFR 91.103, which opens with "Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight", that allows NOTAMS to transfer liability.
Theoretically CFRs are limited to powers specifically authorized by congress, but in practice, they are full of overreach that is only limited when it becomes case law, but the FAA is so powerful that it can effectively shut down any organization trying to dispute them in federal courts, so there isn't really any case law limiting the scope of their CFRs.
https://aviation.stackexchange.com/questions/31058/are-weath...
There REALLY needs to be a unified ATC system that incorporates NOTAMS, traffic, and live position of whatever unmanned stuff is moving around. We have most of the tech deployed already. We have to integrate it.
But to answer your question: yes, if there is a good alternative or the product is replaceable. Twitter is one of those things.
I do actively avoid products produced by a nation which is committing genocide for example and ignores international law.
There were attempts to use balloons as long range weapons in WW2 but they weren't very effective.
Bad actors have a lot of ways to cause damage, most of them much more effective than balloons.
https://windbornesystems.com/mission
I don't think any company would want this record. I am very glad the pilot and the souls on board are safe.
(399 points, 2 days ago, 222 comments) https://news.ycombinator.com/item?id=45636285
(35 points, 2 days ago, 55 comments) https://news.ycombinator.com/item?id=45633191
Related: It was a weather balloon, not space debris, that struck a United Airlines plane (12 points) https://news.ycombinator.com/item?id=45652120
wonder if things would have been different if it hit the center of the window
Interesting, I wonder why is this.
https://windbornesystems.com/blog/ua-1093
https://abcnews.go.com/US/mystery-object-hits-united-airline...
https://www.financialexpress.com/world-news/us-news/injured-...