US Navy’s T-45, F/A-18 oxygen issue still to be resolved

Issues with oxygen systems on the U.S. Navy’s T-45 and F/A-18 aircraft causing physiological episodes (PEs) within naval aviation are yet to resolved, a navy review into the problem revealed.

U.S. Navy student pilots have not been allowed to fly since March this year, following an increase in cases of hypoxia caused by problems with the Onboard Oxygen Generation System (OBOGS).

The number of PE cases reported in 2017 surged compared to the numbers from previous years.

The reason why finding a solution to the problem is difficult, as the review indicates, is the complexity of aircraft human-machine interfaces and the unforgiving environment in which aircrew operate.

Rather than trying to point to a single solution, the U.S. Navy has determined that the way to go forward with the issue is to take a multi-step approach.

The comprehensive review (CR), published by the navy on June 15, examined a number of possible factors and identified steps to be taken to reduce PE numbers and risk.

The CR examined the following factors:
-Organizational factors, including command, control and communications;
-PE analysis and trends;
-PE corrective actions and processes;
-Aircrew breathing air systems;
-Cabin pressurization systems;
-Cockpit environmental monitoring and alerting systems;
-Physiological factors, including aircrew monitoring;
-Aircrew procedures, training and proficiency;
-Maintenance infrastructure and procedures;
-Medical training, emergency response and research;
-PE lessons, including those from other government agencies and countries.

The steps that should be taken to reduce PE numbers and risk include:
-Establish a single, dedicated organization to lead Naval PE resolution efforts. This temporary organization should be headed by a Naval Aviator Flag/General Officer, embrace the “unconstrained resource” approach and fully incorporate all stakeholders.
-Redesign aircraft systems to meet oxygen generation system technical requirements.
-Execute a multi-faceted approach to improve ECS reliability, particularly on the FA-18. This effort must address component reliability, system inspections and testing.
-Embrace and resource a methodical PE root cause corrective action process for each aircraft under the single, dedicated organization tasked to lead PE efforts. Additionally, standardize and improve the PE investigation and adjudication process.
-Establish an integrated life support system program at Naval Air Systems Command that, at a minimum, manages Naval Aviation oxygen generation and connecting systems; cabin environment and pressurization systems; and physiological monitoring. This program must regularly leverage the lessons of other organizations managing similar technologies.
-Address PE reporting shortfalls, including physiological monitoring; aircrew alerting; and cockpit audio, video and habitability recording.

The navy said that, based on the findings of the report, the next Chief of Naval Air Training (CNATRA) would be a more experienced aviation flag officer. The increase in seniority is meant to improve flight safety, address current instructor concerns, and ultimately resume student training. Rear Adm. Jay Bynum, currently serving as Commander, Carrier Strike Group Nine and a two-star admiral select, is scheduled to assume command of CNATRA, later this month.

While the conclusions and recommendations of this CR were developed specifically for the U.S. Navy and U.S. Marine Corps T-45 and F/A-18, PEs are a known problem in other aircraft and services. Elements of this report will be of value to those attempting to address PEs throughout the U.S. military.

You can read the full report here