Abba Tor, whose engineering prowess helped the landmark Trans World Flight Center take wing at Kennedy International Airport — and kept it from cracking apart — died on Feb. 11 in Hastings-on-Hudson, N.Y. He was 93.
The cause was cardiac arrest, his daughter, Shuli Tor, said.
Associated with Eero Saarinen and Louis I. Kahn, pillars of modern architecture, Mr. Tor worked with Mr. Saarinen on the John Deere World Headquarters in Moline, Ill., and the Vivian Beaumont Theater at Lincoln Center in New York, and with Mr. Kahn on the Yale Center for British Art in New Haven.
But he earned his reputation with Trans World Airlines’ birdlike terminal, designed by Mr. Saarinen. It was completed in 1962 and has since been celebrated as a symbol of the jet age.
Most important was his insistence, against Mr. Saarinen’s wishes, that the lobed roof be divided into four discrete vaults, instead of being formed as a single 55,000-square-foot expanse of concrete, without joints.
Otherwise, Mr. Tor warned, the concrete would surely crack, even if it was being poured for a project designed by the eminent Mr. Saarinen.
In a 2008 interview with Kornel Ringli, for Mr. Ringli’s book, “Designing TWA: Eero Saarinen’s Airport Terminal in New York,” Mr. Tor recalled a conversation with John Dinkeloo, one of Mr. Saarinen’s young associates.
“Concrete is dumb,” Mr. Tor said he told Mr. Dinkeloo. “It doesn’t know for whom it is being poured.”
Engineering necessity gave birth to one of the most inviting facets of the terminal’s undulating interior: ribbons of skylights along the joints that were opened among the four vaults. The skylights turn what might have been a heavy blanket into something luminous and billowy.
“Once they were told that they have to make joints, because the structure cannot be poured all at once, they said, ‘Let’s use this requirement to let some light in,’ ” Mr. Tor told Mr. Ringli. “There was a kind of — I would say — tension between the architect and the engineer. But it was a beneficial tension.”
Another example of beneficial tension is the four great sloping Y-shaped buttresses that support the outside corners of the converging vaults. Originally, they were to have been vertical stilts, but wound up looking more like Henry Moore sculptures than hard-working structural elements.
Mr. Tor and Mr. Saarinen stood together under the terminal’s 6,000-ton roof in 1960, just after the formwork and scaffolding needed for the concrete pour had been removed. The vaults held up.
“Mr. Tor,” Mr. Saarinen said, “if this roof were to fall on my head now, I would die a happy man.” He died in 1961, before the building was complete.
Tyler Morse, who is redeveloping the long-empty terminal as the TWA Hotel, met Mr. Tor about six months ago.
“Abba was quoting the vector forces on various points of the four lobes, both individually and where they come together,” Mr. Morse wrote by email. “It was as if he had just finished the engineering calculations that week, not 60 years ago.”
Abba Tor was born on Nov. 1, 1923, in Warsaw, to Aryeh and Rachel Turkeltaub. His father, a Zionist, ran a paper-products business. The family emigrated to Palestine in the early 1930s, before Nazi Germany’s onslaught.
In Haifa, Mr. Tor earned a degree in civil engineering at the Technion, where he met an architecture student, Nomi Blumenthal, whom he married in 1946.
His wife died in 1998. Their son, Daniel, died in 1979. In addition to his daughter, Mr. Tor is survived by a sister, Judith Lukin. He lived in Hastings-on-Hudson.
In 1952, while serving in the Israel Defense Forces, Mr. Tor was sent to the United States to work at the National Bureau of Standards. He earned a master’s degree at Columbia University in the 1950s. He later taught there and joined the leading engineering firm Ammann & Whitney. He returned to Israel in 1963 and remained there until 1967, before settling permanently in the United States, where he founded the firm Pfisterer, Tor & Associates with Henry A. Pfisterer.
Imposing reputations did not faze Mr. Tor. He and Mr. Dinkeloo disagreed on what concrete pouring method should be used for the buttresses at the T.W.A. terminal. As Mr. Tor recalled it, Mr. Dinkeloo warned him that if he did not accede, Mr. Saarinen would have his head on a platter.
“My head will not do him any good on the platter,” Mr. Tor said. “My head has to stay on my shoulders, not on his platter.”