by Kelly Zhou
The U.S. Navy has finished stabilizing the northern hangar at the former Tustin Marine base following a partial roof collapse in October and a delayed construction schedule.
A $35 million airship that was inside the hangar during the collapse has damage that is “beyond repair,” according to its maker, Worldwide Aeros Corp.
Nearby, the southern hangar will undergo a $369,000 structural assessment that the City Council approved earlier this month.
There are two hangars standing on the former Marine Corps Air Station base, used to house blimps and planes during World War II. They are some of the world’s largest freestanding wooden structures, and there are only five other hangars remaining, according to city documents.
An observation room on top of the northern hangar fell through the roof on Oct. 7 and a 25-by-25-foot section of the roof collapsed. The incident damaged the $35 million, 265-foot-long airship inside, causing a helium leak.
The “beyond repair” damage was found when the Navy allowed Worldwide Aeros to inspect the vehicle in early July, said John Kiehle, Aeros communication director, in an email.
The Navy’s contractor, Kellogg Brown & Root Services, Inc., began construction in February, building two 180-foot steel towers to stabilize the northern hangar from the outside.
The towers stand on each side of the hangar and support the damaged roof trusses via tensioned steel tieback cables, according to the Naval Facilities Engineering Command Base Realignment and Closure (NAVFAC BRAC) Program. The 90-day contract was awarded in December, but the deadline to complete construction was later extended.
The stabilization is part of a $3.6 million contract, which includes a forensic analysis to determine the cause of the roof failure and installation of a security fence and lighting, said Melanie Ault, BRAC program coordinator, in an email. The forensic engineering study is expected to be completed this summer, Ault said.
The hangar is expected to be conveyed from the Navy to the county; the other one is to go to the city. As for the city’s hangar, routine maintenance has been deferred presumably since 1991, city Tustin Legacy project manager Matt West said at the June 17 council meeting. The MCAS base’s closure was announced in 1991.
Since 2002, repairs have been made on a case-by-case basis, and the southern hangar was leased to the city in a “mothballed” condition, West said.
“It’s really time for us to complete a comprehensive, multidisciplinary evaluation of the structure,” West said at the meeting.The City Council approved spending just under $369,000 to hire a consultant to conduct an assessment and look at potential ways to reuse the hangar.
The county plans to use the same consultant, Page and Turnbull, to get a cost estimate on repairs for the damaged northern hangar. That contract will likely go before the county Board of Supervisors in August, said Scott Thomas, OC Parks design manager.
The damaged hangar is part of county plans for an 84.5-acre regional park, which are on hold until the assessment is done. That assessment and a cost estimate would then go to the Board of Supervisors to make a decision regarding the future of the proposed park, Thomas said in a previous interview.
The multimillion-dollar airship prototype has been sitting inside the damaged hangar since October. The Navy is now coordinating with Worldwide Aeros to move its silvery zeppelin out of the hangar, according to Ault.
The airship is designed to move cargo quickly over long distances. Aeros is waiting for a license to enter the hangar and move its property, Kiehle said.