TRAVIS AIR FORCE BASE, Calif. --Exercise Sourdough, the Department of War’s largest urban evasion training event, concluded its 11th annual iteration Dec. 11, 2025, after three days of integrated, multi-agency operations across San Francisco. Led by the U.S. Air Force’s 571st Mobility Support Advisory Squadron, the exercise brought together over 150 military and civilian partners to strengthen interoperability, coordination and readiness in an urban environment.
Held Dec. 8–11, the exercise challenged Airmen from various units to evade capture while operating in one of the nation’s most densely populated metropolitan areas. The evading participants navigated the city for up to 36 hours with limited resources, facing realistic opposition forces and making time-sensitive decisions.
Building on more than a decade of collaboration with the San Francisco Sheriff’s Office and the U.S. Coast Guard, this year’s iteration introduced additional agencies and units, including the California Fire Department of Forestry and Fire Protection, SWAT officers from multiple law enforcement agencies, including the Department of Corrections and the University of California Police, as well as from within Travis Air Force base including the 22nd Airlift Squadron and the 60th Aeromedical Evacuation Squadron.
“The addition of several new agencies and units brought new dimensions to the exercise,” said Lt. Col. Mary Lea Bordelon, 571st MSAS commander. “It forced our personnel to adapt to unfamiliar protocols, communication styles and operating procedures. That adaptability is critical to interoperability in joint and interagency environments, and it strengthens our ability to integrate quickly and operate effectively alongside partners in real-world operations.”
The exercise culminated in a multi-stage recovery operation involving 11 evading teams dispersed throughout the city. Extraction methods included rotary wing aircraft, maritime assets and ground transportation, requiring synchronization across multiple agencies.
After all teams were recovered to Moffett Air National Guard Base via helicopter and maritime assets, 10 simulated patients who sustained simulated injuries during evasion were assessed and treated by personnel assigned to the 60th Aeromedical Evacuation Squadron. The patients and remaining participants were then loaded onto a C-5M Super Galaxy assigned to the 22nd AS and airlifted to Travis Air Force Base for final recovery by friendly forces.
“The AE crew confronted the challenge of an unregulated mission where the crew lacked advance knowledge of casualty type or volume,” said Maj. Katelyn Dunahoe, 571st MSAS aeromedical evacuation lead. “They provided critical care by rapidly triaging patients on the ground and delivering in-flight medical care for injuries sustained during evasion. This exercise highlighted the AE crew’s ability to successfully execute complex missions with minimal preparation time.”
While some participants returned with experience from previous iterations, others took part for the first time. Regardless of experience level, the exercise required constant adaptation as teams balanced evasion tactics with situational awareness, resource management and coordination with recovery forces.
“Exercise Sourdough is a mechanism to test and assess our participants’ ability to successfully evade in an urban environment, resist information and operational exploitation and enable them to influence their own recovery efforts,” said Master Sgt. Jeremy Campbell, 571st MSAS weapons and tactics noncommissioned officer in charge. “The training value cannot be understated because there are few frameworks of this magnitude within the Department of War.”
Exercise Sourdough reinforces the shared commitment among military and civilian organizations to enhance readiness through joint training. By integrating diverse partners and operating across realistic urban environments, the exercise can continue to prepare participants to operate together in complex, real-world scenarios.