Air Force is redesigning oxygen system to protect T-6 pilots
By JAMES BOLINGER | STARS AND STRIPES Published: September 14, 2018
The Air Force will redesign and adjust oxygen control levels in T-6 Texan II cockpits to curb problems suffered by pilots flying the training aircraft, according to Air Education and Training Command.
The service grounded its T-6 fleet Feb. 1 after instructor- and student-pilots at several bases suffered hypoxia-like symptoms, which can occur when pilots are deprived of oxygen. The operational pause was lifted Feb. 27.
Thirteen unexplained physiological events were traced to the On-Board Oxygen Generating System, or OBOGS, which will undergo more maintenance and eventually be replaced, according to an AETC statement issued Friday.
Varying levels of oxygen inside the cockpits was a major factor behind the incidents, according to AETC commander Lt. Gen. Steve Kwast. Those variations, which in some cases gave pilots more oxygen than they needed, caused physiological stress.
While most pilots were not impacted by the fluctuations, some suffered symptoms similar to hypoxia, hypocapnia — caused by reduced carbon dioxide — or other similar conditions, Kwast said.
The team investigating the incidents included experts from AETC, Air Force Material Command, NASA and the Navy, which also uses the T-6 to train its pilots. They conducted multiple inspections and discovered that the OBOGS filter and drain valves were failing at a rate much higher than anticipated, the statement said.
AETC and AFMC are now redesigning the T-6 OBOGS system, which is expected to take between two and four years, the statement said.
In the meantime, airmen are working with the aircraft manufacturer to create a software algorithm that will stabilize cockpit oxygen concentrations, the statement added. New maintenance procedures and inspection timelines, and additional pilot training were also introduced to prevent future issues.
“Since our T-6 operational pause, we have made every effort to communicate with every instructor and every student exactly what we’ve found,” Maj. Gen. Patrick Doherty, 19th Air Force commander, said in the statement. “Transparency remains of utmost importance to us as we all work together to ensure that our pilots are safe and know the way ahead.”
The grounding slowed training for the Air Force, which is facing a deficit of about 2,000 pilots amid competition from commercial aviation. Some trainees were transferred to T-38 Talon and T-1 Jayhawk trainers, which prepare pilots to fly fighters, bombers, airlifters and refueling aircraft.