Giant, historic California building engulfed in flames

One of the largest free-standing wooden structures on Earth was destroyed by fire Tuesday morning. 

A historic 17-story hangar at the former Tustin Air Base in Southern California, built to house blimps for use during World War II, is still sending plumes of smoke into the Orange County sky.

Firefighters first responded to the blaze at 1 a.m., and by dawn, Chinook helicopters, 11 fire trucks and at least 70 firefighters were on site to try to quell the flames. Efforts to save the 1,000-foot-long structure have now been abandoned, the Orange County Fire Authority said. 

“Due to the dynamic nature of the fire, and the imminent danger of collapse, we have determined the most operationally sound method is to allow the structure to collapse,” OCFA wrote on social media. “At which point ground crews can move in closer, and aggressively work to extinguish the fire.”

No injuries have been reported, and the cause of the fire is under investigation. 

Built in 1942, the historic landmark, one of two giant hangars at the former Tustin Air Base, once held six of the 12 military blimps at the base that were used to patrol the Pacific for Japanese submarines. The facility even had its own helium-generating plant, and later housed about 100 military helicopters during the Vietnam War.

In recent years, Orange County officials have worked to clean up the unused site, spending more than $300,000 to remove old equipment and fire-prone debris piles. 

Authorities said residents should expect to hear large crashes and see a spectacular collapse, as the 81-year-old historic landmark falls back to earth in the coming hours or days.