Rogue Weather Balloon Shatters Airliner Windshield, Injures Pilot in Midair Collision
A harrowing midair incident that forced a United Airlines flight to make an emergency landing last month has been attributed to a stray weather balloon, according to a new National Transportation Safety Board (NTSB) report. The October 16 collision shattered the Boeing 737’s windshield at 36,000 feet, injuring the captain and creating moments of intense uncertainty for everyone aboard. This event highlights the unexpected hazards that can emerge even in the carefully controlled realm of commercial aviation, where pilots must be prepared for virtually any contingency.
The dramatic incident unfolded as United Flight 1093 cruised over Utah on its way from Denver to Los Angeles. The captain had just spotted an unidentified object on the horizon when, without warning, it slammed into the aircraft with what the report described as a “loud bang.” The impact was severe enough to nearly blow out one of the multi-layered cockpit windshields, showering both pilots with glass fragments. Despite suffering multiple cuts to his right arm, the captain maintained control of the aircraft, while his first officer emerged uninjured. Their quick decision-making and professional response ensured the safety of the 111 passengers onboard as they diverted to Salt Lake City International Airport. Fortunately, cabin pressurization remained intact throughout the emergency, preventing what could have been a far more catastrophic situation.
Investigators traced the culprit to a high-altitude global sounding balloon launched by California-based aerospace company WindBorne Systems. The balloon had been released from Spokane, Washington, the day before the incident and had followed an unusual flight path—drifting south through Nevada before looping back northward into Utah. By the time of the collision, WindBorne had already lost contact with their wandering atmospheric research platform. Photos shared after the incident revealed the sobering reality of what happened in the cockpit: the captain’s arm bruised and bleeding, with broken glass scattered across instruments and controls. The images serve as a stark reminder of the physical dangers that can suddenly confront flight crews, who must continue performing their duties regardless of personal injury.
The NTSB report noted an important technical point that underscores the severity of the impact: aircraft windshields are specifically engineered to withstand strikes from birds weighing up to four pounds without cracking. WindBorne Systems has emphasized that their balloons are designed to minimize damage in case of aircraft collisions, with no large metal components or high-stiffness structural parts. However, the extensive damage caused to the commercial jetliner suggests that even these safety-oriented design choices were insufficient to prevent a dangerous situation. The incident reveals a potential gap in aviation safety planning, as the proliferation of various objects in airspace—from drones to weather balloons—creates new collision risks that traditional safety systems may not fully address.
In response to the incident, WindBorne Systems has announced four significant safety improvements to their balloon operations. These include reducing the time their balloons spend in commercial airspace, enhancing air traffic control notifications, developing new collision-avoidance algorithms, and further reducing the mass of their balloons to minimize potential damage from any future impacts. “We are deeply relieved that Flight UA 1093 landed safely and with minimal damage,” the company stated, acknowledging the gravity of what occurred. Their response reflects the aviation industry’s commitment to learning from each incident and implementing changes that can prevent similar occurrences in the future, a principle that has historically driven improvements in air safety worldwide.
While the NTSB investigation continues, this incident serves as a reminder of the complex interplay between different users of our shared airspace. Commercial aviation operates with remarkable safety records precisely because the industry treats each near-miss or accident as an opportunity to identify and address vulnerabilities. The collision between United Airlines Flight 1093 and the WindBorne weather balloon represents a rare but instructive case study in how even well-designed systems can sometimes interact in unexpected and dangerous ways. As our skies become increasingly crowded with various aircraft, drones, balloons, and other flying objects, the lessons learned from this incident will likely inform new safety protocols and technologies aimed at preventing future midair collisions, ensuring that air travel remains one of the safest forms of transportation available to the public.
