He was a 30-year-old hydraulic engineer with no pilot's license in 1947 when he co-piloted Howard Hughes' storied leviathan known as the Spruce Goose.
He was 63 and still creating hydraulic systems for Hughes Aviation in 1980 when the 200-ton aircraft emerged from the hangar where Hughes had sequestered it three decades earlier. The Flying Boat went on display in 1982 under a dome beside the Queen Mary at Long Beach Harbor.
And he was 76 when the historic plane was dismantled, shrink-wrapped and shipped off to McMinnville, Ore., for another permanent exhibition.
David Grant, who once said "if there is anything close to my heart, it is that airplane," died Thursday. He was 84.
Grant, who lived for many years in Encino and later moved to Calabasas, joined the eccentric aviator in 1946 as one of the original employees of Hughes Aircraft Co. Grant designed the plane's hydraulic system, but the contract to build the plane was rooted in World War II, which had just ended.
Congress ponied up $18 million for the project, and Hughes added $7 million of his own money, to create a troop-and-cargo ship the like of which had never been built and has not been since.
Constructed of laminated birch, because the government contract forbade use of scarce metals, the 210-foot-long plane had a tail section eight stories high and a wingspan of 319 feet. It was designed to carry 700 soldiers plus equipment.
Hughes himself called the craft the Hughes Flying Boat, or Hercules. He detested the tag "Spruce Goose," as did Grant and others who worked on the plane.
"It annoyed Howard and all of us," Grant said in 1987. "It is much too significant an aircraft to be called that."
It was in 1947 that a derisive U.S. Sen. Owen J. Brewster gave the amphibious plane the name that stuck, accusing Hughes of pouring government millions into a boondoggle that would never get off the ground.
Test flights were planned for early 1948. But Grant said he became suspicious Nov. 2, 1947, when Hughes invited news media and the public to observe taxi runs in Long Beach Harbor.
Assigned to ride shotgun despite his lack of a pilot's license, Grant said Hughes really didn't want a viable co-pilot "because he might interfere" and had set up the controls to give Grant little to do.
After a couple of test runs, Grant related, Hughes had reporters get off the plane and lined up the press boats to give them a good view.
"Then he casually turned to me," Grant said, "and told me to lower the flaps to 15 degrees--that's takeoff position. He shoved the throttles forward and away we went."
The plane climbed to 70 feet, flew about that many seconds, then dropped back to a perfect watery landing and thousands of cheers.
"It was ecstasy all the way. It was like walking on air," Grant said at a gathering marking the event's 40th anniversary, in 1987. "It wasn't underpowered at all, and it performed exactly like it was designed to."
Hughes' impulsive flight "wasn't much of a flight," Grant added, "but it was enough to quiet Congress down."
The plane never flew again, much to the disappointment of Grant and other team members who had spent years laboring on it all day and then meeting with Hughes at his home into each night.
Grant often speculated that Hughes, who locked his Hercules into a temperature- and humidity-controlled hangar in 1954, simply lost interest or didn't want anyone but himself to fly it and never had the time. The war had ended, and a massive troop transport craft was no longer a priority.
Grant, who retired in 1981, also worked on the XH-17 helicopter and the hydraulic systems for lunar landing craft, among other Hughes projects.
Born in Detroit, Grant earned a bachelor's degree in aeronautical engineering from the University of Michigan.
He is survived by his wife of 61 years, Ruth; a daughter, Diane Grant Brinegar; a son, James; a sister, Florence Lenhard; and five grandchildren.
Services are private. The family has asked that any memorial donations be made to a charity of the donor's choice.