Defense News was first to report this new incident, which occurred approximately 60 miles south of Seattle, Washington. The EA-18G, assigned to Air Test and Evaluation Squadron Nine (VX-9), was flying at approximately 25,000 feet on a mission from Naval Air Station Whidbey Island, between Seattle and Vancouver BC, when the cockpit temperature plummeted to -30 degrees Fahrenheit.
The broken environmental control system (ECS) also let in a fine mist of liquid, which then froze, coating the inside of the canopy and vital flight instruments in an opaque sheen of ice. The ECS consists of a number of sub-components that are supposed to work together to manage oxygen flow to the crew, as well as cockpit pressure and temperature.
Despite using up all of their emergency oxygen supply, the crew was able to wend its way its way back to Naval Air Station Whidbey Island with help from air traffic controllers on the ground and their smart watches. In July 2017, Navy Hornet, Super Hornet, and Growler pilots each got a $450 Garmin Fenix 3 wristwatch
$345.00 at WalMart.
, which can measure air pressure and altitude and display an individual’s course heading.
The service issued the watches in order to provide a backup alert mechanism in case the ECS' on-board oxygen generation system, or OBOGS, malfunctioned and cockpit pressure dropped to unsafe levels and the aircraft's built-in safety mechanisms and warning systems also failed. The Navy had not publicly stated that it could serve as a improvised navigational aid in an emergency.
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