The National Transportation Safety Board (NTSB) has released its preliminary report on a significant incident involving a United Airlines Boeing 737 MAX 8, which collided with a commercial weather balloon while cruising at 36,000 feet over Utah last month. The collision, which occurred on October 16, 2025, damaged the cockpit’s windshield and resulted in minor injuries to the aircraft’s captain.
According to the NTSB, United Flight 1093 was en route from Denver to Los Angeles when it struck the balloon shortly after passing Moab, Utah. The captain reported seeing an object in the distance just before the collision, which produced a loud bang and caused glass shards to shower into the cockpit. The captain sustained lacerations to his right arm, but fortunately, the aircraft was able to divert safely to Salt Lake City.
Details Unfold on Weather Balloon Collision
The investigation revealed that the weather balloon involved was a high-altitude global sounding balloon (GSB) launched by WindBorne Systems from Spokane, Washington, on October 15, 2025. The NTSB tracked the balloon’s path, confirming that it had entered Utah’s airspace at the time of the incident. The report states, “The GSB traveled south through Oregon and Nevada before turning northeast, crossing through Utah at the time of the accident.”
NTSB Chair Jennifer Homendy expressed concern over the potential severity of the incident, stating that the collision “could have been really devastating for the aircraft and those on board.” Although only the captain was injured, the damage to the aircraft could have led to catastrophic results.
The cabin’s pressurization remained stable throughout the incident, and while there was a brief indication of an issue with the first officer’s window, no further complications arose. WindBorne Systems indicated that their GSBs are designed to minimize damage during collisions, using materials that do not include large metal or high-stiffness structures.
Aircraft Remains Grounded Following Incident
The aircraft involved, a two-year-old United 737 MAX 8 with registration N17327, has not returned to service more than a month after the collision. Following the incident, it made a brief flight to Chicago Rockford on October 19 and has since remained grounded. The damaged windshield was removed and sent to the NTSB Materials Lab in Washington, D.C., for further examination.
Aircraft windshields are constructed to withstand substantial impacts. They are certified to endure hits from a four-pound bird without penetration and feature non-splintering internal layers. The windshield on the United 737 MAX, manufactured by PPG Aerospace, consists of multiple layers designed to protect against various hazards.
The NTSB has emphasized the importance of understanding and addressing such incidents. WindBorne Systems has committed to enhancing air traffic alerts and reducing the time GSBs spend in commercial airspace to prevent future occurrences. Following this incident, the aviation community is closely monitoring safety protocols to ensure the well-being of both aircraft and passengers.
Simple Flying has reached out to United Airlines for further comments regarding the incident and will provide updates as more information becomes available.
