Speculation was rife this week about the object that smashed the cockpit windscreen of a United Airlines plane on 16 October 2025, mid-flight between Denver and Los Angeles, wounding a pilot and forcing the aircraft to divert to Salt Lake City International. The aircraft was able to land safely thanks to the fact that aircraft windscreens are multi-layered to prevent a catastrophic loss of pressure in case of damage.
The United States National Transportation Safety Board (NTSB) immediately began investigating the incident, including laboratory testing of the damaged windscreen and “radar, weather, and flight recorder data,” the agency said.
But that did not stop the internet rumour mill whirling with possibilities, given that another object travelling outside at high speed appeared to have struck Flight UA1093. Experts fed the frenzy with talk of space debris, and much commentary was driven by photographs appearing to show scorching and sheared rivets on the upper right of the windscreen. The nature of that damage, and the altitude of the aircraft at the time of the collision (36,000 feet), prompted some to dismiss the idea that the cause could be a bird strike.
On October 16, 2025, United Airlines flight UA1093, a Boeing 737 MAX, had to make an emergency landing in Salt Lake City after its windshield was cracked by an unknown object while flying from Denver to Los Angeles. One pilot sustained arm injuries, and while the exact cause is… pic.twitter.com/ByXPRyOjXZ
— Ranger H (@RangerH338) October 19, 2025
By Monday, 20 October, the CEO of WindBorne Systems (a weather tech and AI-powered company based in Palo Alto, California) said in a statement that it believes one of its weather balloons was responsible for the strike.
WindBorne said it has carried out over 4,000 launches and notifies the Federal Aviation Administration (FAA) every time. “We are working closely with the FAA on this matter,” the company said. “We immediately rolled out changes to minimize time spent between 30,000 and 40,000 feet.”
WindBorne’s CEO was quoted as saying: “We learned about UA1093 and the potential that it was related to one of our balloons at 11 pm PT on Sunday and immediately looked into it. At 6 am PT, we sent our preliminary investigation to both NTSB and FAA, and are working with both of them to investigate further.”
Here's what the operational part of the @WindBorneWx weather balloon looks like – they use sand as ballast. And here's the plane, I now understand why the paint on the window frame looks like it's been sand blasted.
— Scott Manley (@DJSnM) October 21, 2025
It does look like WindBorne are doing all the right things,… pic.twitter.com/xGtqlpHjMd
To date, WindBorne, founded by Stanford graduates in 2019, has raised €25 million in funding, with the last round in 2024. With a mission to “help humanity mitigate and manage the most immediately destructive aspects of climate change: extreme weather and weather uncertainty,” through its instruments, WindBorne says it is “building a planetary nervous system to make the world safer and more sustainable for everyone.” In this instance, it’s not certain the 134 passengers and six crew aboard Flight UA1093 would agree. Neither necessarily would NTSB Chair Jennifer Homendy, who said “in the wrong situation” the collision “could have been really devastating for the aircraft and those on board.”
