The Growler's pilot and electronic warfare officer were injured Dec. 16 at Whidbey Island Naval Air Station in Washington state as it prepared for a training flight. The Navy said at the time it was an "on-deck emergency" that involved the aircraft's canopy but did not elaborate.
The Navy suspended flight operations for Growlers and Super Hornets throughout the fleet for several days while they conducted an initial investigation. Super Hornets were included in the stand-down because they share common aircraft systems with the Growler, the Navy said in a statement. Several Super Hornet squadrons are based at Oceana Naval Air Station in Virginia Beach.
The Naval Safety Center classified the incident as a "Class A" mishap, its most serious type. It means there was at least $2 million in damage to the Growler or a "permanent total disability" to a crew member.
The pilot and electronic warfare officer were taken to a hospital to be treated for their injuries. The Norfolk-based Naval Safety Center described the officers' injuries as "severe." The center did not provide any more details.
The Growler is a variant of the F/A-18F Super Hornet and is capable of offensive electronic jamming, electronic emissions detection and electronic suppression of enemy air defenses.
The Navy said Naval Air Systems Command and Boeing engineers identified several factors that likely contributed to the incident. Naval Air Forces ordered changes to be implemented throughout the F-18 fleet because there are similarities in the component designs for the affected systems in the Growler incident, the Navy said in a statement.
The measures include changes to "aircraft water-wash procedures" and updates to the Navy's procedures for ground emergencies. Flight operations resumed on Dec. 19.
The Growler mishap remains under investigation.