GKN Aerospace is preparing to bring portions of its Garden Grove, California facility back online after a safety-related shutdown that began in late May. The interruption followed an overheating problem in a chemical tank that raised concerns about a potential rupture and led to wide-ranging evacuations in the surrounding community.
Employees started returning to the plant this week to carry out safety inspections and other preparatory steps, according to an industry source and an online notice posted by the Orange County Health Care Agency. The initial restart will be limited to areas deemed unaffected by the incident, the source and the agency notice said.
The Garden Grove site, located in a Los Angeles suburb, supplies transparent aircraft components including cockpit and passenger windows used by major aerospace manufacturers. Customers named in company and industry disclosures include Boeing, Airbus for its A350 program, and Lockheed Martin for F-35 canopies.
The work resuming at the facility is reported to cover machining and assembly of transparent materials for cockpit windows and canopies. The notice from the county health agency specified that the initial work would not include the manufacturing of acrylic, a material tied to the chemical involved in the late-May incident.
Company comment was not immediately available. GKN is owned by Melrose PLC, a UK-based company.
Regulatory and investigative activity
Multiple agencies have opened inquiries into the event. The U.S. federal government and the Orange County District Attorney's office under Todd Spitzer have launched investigations, and California's Occupational Safety and Health division is conducting inspections at the site.
The emergency response in late May was triggered by a thermal issue identified in a tank holding methyl methacrylate, a chemical used in producing plastics and resins. Authorities at the time warned the tank could rupture, potentially releasing up to 7,000 gallons (26,500 litres) of hazardous material. Firefighters later assessed and declared that the tank was no longer at risk.
Workforce and capacity context
The Garden Grove plant employs roughly 500 people and had been in the process of expanding its operations to meet rising demand from both commercial aviation and defense programs. In 2024, GKN announced plans for a new production line near the facility that is intended to double capacity for F-35 canopy manufacturing, with the expansion scheduled for completion by January 2027. At the time of that announcement, GKN cited demand from aircraft manufacturers and aftermarket customers.
Industry sources note that only a small number of suppliers produce the specific transparent components used for cockpit and canopy applications. Names mentioned by sources include PPG and Saint-Gobain. PPG has said it is aware of the incident and is monitoring developments. Saint-Gobain and Boeing did not immediately provide comment.
Customer responses and supply considerations
Airbus indicated that production of its A350 program is not currently affected, saying it has adequately managed inventories. Lockheed Martin stated it is collaborating with stakeholders and other supply chain partners to evaluate options and ensure continued delivery of the critical canopy capability to the warfighter.
As GKN brings back employees to perform safety checks and recommence limited machining and assembly activities, investigators and customers will continue to weigh any broader supply-chain implications while inspections proceed.