Most airplanes in the world have vertical tails or rudders to prevent Dutch roll instabilities, a combination of yawing and sideways motions with rolling that looks a bit like the movements of a skater. Unfortunately, a vertical tail adds weight and generates drag, which reduces fuel efficiency in passenger airliners. It also increases the radar signature, which is something you want to keep as low as possible in a military aircraft.

In the B-2 stealth bomber, one of the very few rudderless airplanes, Dutch roll instabilities are dealt with using drag flaps positioned at the tips of its wings, which can split and open to make one wing generate more drag than the other and thus laterally stabilize the machine. “But it is not really an efficient way to solve this problem,” says David Lentink, an aerospace engineer and a biologist at the University of Groningen, Netherlands. “The efficient way is solving it by generating lift instead of drag. This is something birds do.”

Lentink led the study aimed at better understanding birds’ rudderless flight mechanics.

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Over the Northern Hemisphere's summer, the world's temperatures hovered near 1.5° C above pre-industrial temperatures, and the catastrophic weather events that ensued provided a preview of what might be expected to be the new normal before mid-century. And the warming won't stop there; our current emissions trajectory is such that we will double that temperature increase by the time the century is out and continue beyond its end.

This frightening trajectory and its results have led many people to argue that some form of geoengineering is necessary. If we know the effects of that much warming will be catastrophic, why not try canceling some of it out? Unfortunately, the list of "why nots" includes the fact that we don't know how well some of these techniques work or fully understand their unintended consequences. This means more research is required before we put them into practice.

But how do we do that research if there's the risk of unintended consequences? To help guide the process, the American Geophysical Union (AGU) has just released guidelines for ensuring that geoengineering research is conducted ethically.

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London's Great Exhibition of 1851 attracted some 6 million people eager to experience more than 14,000 exhibitors showcasing 19th-century marvels of technology and engineering. The event took place in the Crystal Palace, a 990,000-square-foot building of cast iron and plate glass originally located in Hyde Park. And it was built in an incredible 190 days. According to a recent paper published in the International Journal for the History of Engineering and Technology, one of the secrets was the use of a standardized screw thread, first proposed 10 years before its construction, although the thread did not officially become the British standard until 1905.

“During the Victorian era there was incredible innovation from workshops right across Britain that was helping to change the world," said co-author John Gardner of Anglia Ruskin University (ARU). "In fact, progress was happening at such a rate that certain breakthroughs were perhaps never properly realized at the time, as was the case here with the Crystal Palace. Standardization in engineering is essential and commonplace in the 21st century, but its role in the construction of the Crystal Palace was a major development."

The design competition for what would become the Crystal Palace was launched in March 1850, with a deadline four weeks later, and the actual, fully constructed building opened on May 1, 1851. The winning design, by Joseph Paxton, wasn't chosen until quite late in the game after numerous designs had been rejected—most because they were simply too far above the 100,000-pound budget.

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