U.S. Navy officials.

The hangar is one of two on the former Marine Corps Air Station base that was used to house blimps and planes during World War II. An observation room on top of the hangar fell through the roof on Oct. 7, and a 25-by-25-foot section of the roof collapsed. The incident also damaged a $35 million, 265-foot-long airship inside, causing a helium leak.

In February, the Navy’s contractor, Kellogg Brown and Root Services Inc., began building two 180-foot steel towers on each side of the hangar. The towers will stand outside and support the damaged roof trusses via tensioned steel tieback cables, according to the Naval Facilities Engineering Command Base Realignment and Closure Program.

The stabilization via steel towers is part of a $3.2 million contract, according toSarah Ann Moore, acting base closure manager for the former MCAS Tustin.

The Navy originally awarded the contract at the end of December, and Kellogg Brown and Root Services was given until the end of March to complete design and construction. But the deadline has since been extended, with hangar stabilization to be finished by the end of this month, Moore said.

The multimillion-dollar zeppelin, a prototype by Worldwide Aeros Corp., is designed to move cargo quickly over long distances. It has been sitting inside the damaged hangar since October.

Unless unexpected conditions occur, Aeros will be able to access the hangar on May 1 “to begin disassembly and removal of its property,” Moore said.

The hangar is being prepared to be conveyed from the Navy to the county. It’s included in