A United Airlines flight from San Diego to New Jersey was grounded early Tuesday morning after a lithium-ion battery pack burst into flames in the cabin.
Four flight crew staff were taken to the hospital after suffering smoke inhalation and two passengers reported injuries, officials said.
The battery exploded shortly after the plane took off from San Diego International Airport and was inside the back pocket of a seat in first class, according to a statement from United. The flight crew “acted quickly” to contain the fire by putting the battery into a thermal containment bag.
The Newark-bound flight reversed course and returned to the San Diego airport where it was met by emergency personnel.
“We thank our crew for their quick actions in prioritizing the safety of everyone on board the aircraft and we are making arrangements to get our customers to their destinations,” United said.
Lithium-ion batteries are commonly used in electronic devices and can explode if they short-circuit or overheat. Fires caused by lithium-ion batteries are on the rise and have proven difficult for firefighters to put out, because the cell batteries are often tightly confined inside casings that don’t allow water to easily penetrate.
Lithium-ion batteries were responsible for 57 incidents on-board U.S. flights in 2022, according to the Federal Aviation Administration (FAA).
According to the Canadian Air Transport Security Authority (CATSA), most batteries are “generally safe for air travel” in carry-on luggage but they recommend checking with airlines about whether they can be packed in checked baggage.
“Infrequently, batteries can short-circuit and overheat and in some cases cause sparks or a fire,” the agency notes.
When travelling with a battery pack, CATSA recommends putting it in a case, leaving it in its original packaging, or taping over the battery’s terminals.
“Prevent crushing, puncturing, or putting pressure on the battery, as this can cause an internal short circuit and result in overheating,” the agency wrote.
It’s unclear as of this writing if charges will be laid against any passenger.