A weather balloon may have been the culprit that cracked a United Airlines plane’s windshield while the flight was en route from Denver to California, according to investigators.
United flight 1093 took off from Denver International Airport at 5:51 a.m. Thursday and was cruising at approximately 36,000 feet above Utah when its windshield cracked, according to flight tracking software FlightAware and federal investigators.
Now, a company responsible for manufacturing weather balloons and collecting atmospheric data is saying that one of their balloons likely collided with the plane, causing the damage.
WindBorne Systems, which has previously partnered with the National Oceanic and Atmospheric Administration on weather research, was first alerted to the fact that one of its balloons may have been responsible for the plane’s cracked windshield and subsequent diversion late Sunday night, three days after the incident, company spokesperson Kai Marshland said.
Within hours, the company sent a preliminary report to the National Transportation Safety Board and the Federal Aviation Administration, Marshland said. Company officials are working with both federal agencies to investigate further.
“We are grateful that, to our knowledge, there were no serious injuries and no loss of pressurization,” WindBorne officials said in a statement. “… We immediately rolled out changes to minimize time spent between 30,000 and 40,000 feet. These changes are already live with immediate effect.”
Commercial planes most often fly between 31,000 and 42,000 feet, according to the California Aeronautical University.
WindBorne also plans to use live flight data to allow its weather balloons to autonomously avoid planes, even if planes are flying at a nonstandard altitude, according to the company’s statement.
The company has recorded more than 4,000 weather balloon launches, actively coordinating with the FAA and filing aviation alerts before each launch, according to WindBorne’s statement. The balloons weigh roughly 2.4 pounds at launch and get lighter throughout the flight.
“The system is designed to be safe in the event of a midair collision,” WindBorne officials stated.
United Airlines spokesperson Russell Carlton previously said that airplane windshields are designed with multiple layers and can still function safely if one of those layers is cracked. Carlton was unable to answer additional questions on Monday, including whether the pilot was injured by the cracked glass.
The Thursday flight was safely diverted to Salt Lake City International Airport, where the 134 passengers and six crew members on board switched planes and continued their journey to Los Angeles, Carlton said. The new plane touched down in California at about 1:23 p.m. PDT, nearly six hours late, according to FlightAware.
NTSB officials did not respond to multiple requests for comment.
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