A Marine Aerial Refueler Transport Squadron carrying 46 passengers out of MCAS Miramar lost pressurization during a scheduled training mission, leaving some Marines sick.
The incident happened Tuesday at approximately 11:20 a.m. when the C-130J left Marine Corps Air Station Miramar, according to a statement from the U.S. Marine Corps.
At 21,000 feet, the plane experienced a loss of pressurization.
The air crew executed appropriate procedures and safely landed back at Miramar, officials said.
Four Marines and one Sailor from the Camp Pendleton-based 3rd Low Altitude Air Defense Battalion had symptoms of decompression sickness the next day. They were treated at Naval Medical Center San Diego and released; they did not require hospitalization.
The incident is under investigation.
No further information is available.
