For those who weren't here to see the real thing 65 million years ago, a team of Simi Valley inventors is building a lifelike, flying replica of a pterosaur, the largest creature ever to take wing.
Employing new lightweight materials and robotics, the group plans to construct the pterosaur (TER-o-sar) replica with a 36-foot wingspan that flies by flapping its wings once a second, just like the original.
With hairy, leather-like skin, the replica also will be nearly indistinguishable from the original--or at least from the scientific community's best guess at what the real thing looked like.
The project is the latest idea of Paul MacCready, whose Gossamer Albatross in 1979 was the first human-powered aircraft to cross the English Channel.
Smithsonian Footing Bill
The Smithsonian Institution, which plans to display the pterosaur after flying it down the mall in Washington, D.C., next year, is picking up the $400,000 cost of the project.
Film of the development and hoped-for flight of the pterosaur will be incorporated into a 34-minute movie, "On the Wing," that will be shown regularly at the Smithsonian's National Air and Space Museum.
The 59-year-old MacCready said he assigned the pterosaur project to members of the Simi Valley branch of his Monrovia-based engineering firm, AeroVironment Inc., because "they're the best crew in the world for this sort of advanced work, and they're always eager to jump in."
The 10-member team of designers and craftsmen, which includes his sons, Tyler and Parker, most recently developed the Bionic Bat, another human-powered aircraft designed by MacCready.
Bat Set Speed Record
In competition sponsored by Great Britain's Royal Aeronautical Society, the 84-pound bat set a world speed record--23.45 m.p.h.--for human-powered flight over a one-mile course.
MacCready said previous attempts to develop craft that fly by wing-flapping were limited to small wooden craft driven by rubber bands.
Nonetheless, he expressed confidence that his development crew, which began work on the flying reptile six months ago, would not only be able to make the pterosaur fly, but also would be able to control it from the ground.
Martyn Cowley, 36, an architect turned aircraft builder who was project director of the Bionic Bat and is participating in the pterosaur development, was more reserved.
In an interview, he prefaced many of his statements with, "If we are able to make it fly . . ."
'Awed by the Magnitude'
Cowley said at times he is "awed by the magnitude of what we are trying to do. This is far, far more complex than human-powered flight and, if we are successful, will be a far greater triumph."
He said that scientific literature was of almost no use in determining how animals are able to fly by flapping their wings.
"We have found out there's a lot more to it than just pushing wings up and down," he said. "There are thousands of subtle little movements involved, many of them related to the crucial problem of controlling direction."
The team has built a model with an 18-foot wingspan that they pulled behind a van in flight-testing.
Unlike the final pterosaur, which will be twice the model's size and have flexible, flapping wings, the model has rigid, fixed wings, similar to an airplane's.
"We're still testing out basic ideas," said Cowley. "We haven't yet made the big jump into wing-flapping."
Before the advent of birds, pterosaurs, also called pterodactyls, filled the skies, their fur-covered, leathery wings casting giant shadows, scientists say.
Unlike birds, which have wings made of feathers, pterosaurs were reptiles and had wings consisting of a membrane of skin stretched over a bony structure, much like the wings of bats.
As plotted out by MacCready, the pterosaur replica will weigh 140 pounds and will be able to fly for about five minutes at 27 m.p.h.
The replica will contain two gyroscopes connected to a computer that will send compensating instructions to the motors that flap, sweep and twist the wings.
On the ground, a pilot will send generalized instructions to the craft to change its speed, attitude and direction.
In a telephone interview, Walter J. Boyne, director of the National Air and Space Museum, predicted that the flight down the mall, tentatively scheduled for May, would be a "sensation."
He said that a six-foot, leather-like wing that the development team recently completed was "amazing in its fidelity to what we presume the original looked like. It was lifelike, yet lightweight and strong."