It remains one of the greatest of all mysteries: How did the ancient Egyptians build the pyramids?
Many scholars believe the historic feats were probably accomplished by thousands of workers using brute force and ramps to move the massive stones to great heights.
A team from Caltech says the task could have been a lot less strenuous: The Egyptians may have simply hoisted the multi-ton blocks with kites.
Skeptical? Consider its latest experiment.
Atop a desert hill outside Palmdale on Saturday, the team lofted a nylon para-sail into 16-mph winds and cheered as it grabbed a gust of wind and yanked up an obelisk weighing nearly 3 1/2 tons.
Although their modern effort to solve one of antiquity's greatest puzzles draws scoffs from many experts, the success fortified the team's theory that trade winds may have provided the fuel to erect some of the wonders of the ancient world.
"Maybe there were creative thinkers who figured it out, and the Egyptians didn't just use brute force," said Emilio Castano Graff, the Caltech student who led the project.
"This doesn't prove the Egyptians used kites to build the pyramids, but it shows that it is possible to use the energy of the wind to lift heavy objects," Graff said.
The lift of the obelisk--a four-sided pillar with a pyramid top--was the latest success for the team that took on the project partly as an engineering challenge and partly as an attempt to add to the knowledge of ancient engineering practices.
The team includes Graff, a mathematical whiz kid and aspiring race car designer, his aeronautics professor Mory Gharib and kite-surfing expert Eric May.
Although all three bring formidable skills to the project, the idea sprung from the curious mind of a Reseda businesswoman turned amateur Egyptologist. Maureen Clemmons, 44, simply doesn't believe that the Egyptians could have done it the way most people think they did.
Egyptologists Skeptical of Kite Theory
She began testing her theory by lifting a 400-pound obelisk with a 3-foot-by-4-foot para-foil. She also found symbolic figures in Egyptian history that she said suggest they used kites.
Her theories, however, don't stir much interest among most scholars of Egyptian history and archeology. According to Willeke Wendrich, an assistant professor of Egyptian archeology at UCLA, no evidence exists that kites were used to build the pyramids. She said tomb drawings and other artifacts only point to ramps, levers and other techniques.
"There are no indications that they used kites, let alone used them for lifting such an enormous weight," she said. "We have no depictions. We don't even have words in Egyptian for kite."
But Clemmons has persisted. She pitched her idea to Caltech engineers who decided to take on the project after mathematical calculations showed it was indeed possible. Since then the team has conducted at least three tests, most of them successful.
Here's how it works:
An obelisk lying on its side is connected to a para-sail through a scaffold and pulley system. When the sail fills with wind and stretches the rope, the pulling force lifts the obelisk. A rolling platform helps set the stone in a vertical position.
The key lies in steering the kite to maximize the wind power. It must be maneuvered sideways or down to create the greatest pull. The team uses an ordinary parachute, and wind gusts of 12 mph are all that is needed to generate the lift.
On Saturday, the team had more fuel than necessary as winds ranged from 12 mph to 22 mph.
After a brief countdown, four assistants set the para-sail loose, and the initial upward thrust of the kite jerked the obelisk almost to its full 15-foot height. Then May, the kite-surfer, tried to steer the sail. The winds were so strong, however, that it pulled him off the ground and almost launched him into the air.
Attempting to Imitate Ancient Materials
After letting the para-sail collapse, the team tried again. This time, the wind whipped the para-sail with such force that the obelisk straightened with a sudden jerk.
Total air time to lift the obelisk: about 25 seconds.
"It's a lot easier than hip-chugging stones all day," said Clemmons.
The team's next goal is to downgrade the tools used in their experiment. They want to replicate how Egyptians may have done it, so they will use linen, instead of nylon sails. They will also use hemp ropes that were commonly used in that era.
Eventually, the team dreams of erecting its own pyramid in the shadow of the Giza pyramids. "I feel we will rewrite a piece of history," said May.