With three times the billings of its nearest competitor, Daniel, Mann, Johnson & Mendenhall is a big firm that takes on big projects.

The L.A.-based architectural firm has had a longstanding tradition of working on massive government projects from the launch pads at Cape Canaveral to the Pentagon renovation.

DMJM employees, in fact, were working in the Pentagon when a hijacked commercial airliner crashed into the complex last week. All were safe and accounted for, according to a company spokeswoman.

“We did have staff in the Pentagon and thank goodness none of them were harmed,” said Lesley Grant, a vice president of marketing and communications.

DMJM is working on a 15-year joint contract with 3D/International on renovation of the Pentagon, part of a $1.2 billion, 20-year project to update the building. DMJM’s portion of the contract is worth $75 million.

There were 89 employees from the two companies in the Pentagon when the attack occurred, but there was no information about how many were DMJM employees.

At 6.6 million square feet, the Pentagon is one of the world’s largest office buildings. Held up by 41,492 concrete piles, the five-sided building covers 29 acres and has 17.5 miles of corridors and 7,748 windows.

The renovation project has been described by Civil Engineering magazine as “one of the most ambitious, complex and challenging construction undertakings in contemporary history.”

For perspective, the strictly-budgeted project involves gutting space equivalent to three Empire State Buildings and renovating them floor to ceiling without interfering with the working of the Department of Defense.

Defense Department work is nothing new for DMJM. Since forming in the aftermath of World War II, the company has performed work for the Navy as well as the Air Force, which provided three-quarters of the firm’s business in the 1950s.

DMJM was also dubbed the “architects for the space age” by Fortune magazine because it designed the launch pads at Cape Canaveral.

DMJM architects or engineers are responsible for such American landmarks as the Superdome in New Orleans and Air Force One Maintenance Facility and Support Complex at Andrews Air Force Base.

In an eerie coincidence, construction of the Pentagon began Sept. 11, 1941, 60 years to the day before last week’s plane crash.