The Blade That Would Make Helicopters Almost Silent [Helicopters]

Helicopters make a lot of noise because of a physical phenomenon called blade-vortex interaction. Eurocopter engineers have developed a new kind of rotor blade that attenuates this problem. It's called Blue Edge, and—as you can hear—it works beautifully:

The new blade shape is combined with another technology called Blue Pulse, which adds three flaps to the edge of the rotor blades. These flaps move up and down at 15 to 40 times per second, using piezoelectric motors that also help to reduce the blade-vortex interaction.
[Gizmodo via Autopia]

NASA developing an airbag for helicopters — for the entire 'copter [NASA]

NASA's "deployable energy absorber" may appear to be a couple of oversized sponges attached to the bottom of a helicopter, but you could be looking at a safety system that helps occupants survive a helicopter crash — or even any kind of air-to-ground impact.
It's a bit like an airbag for helicopters, one that NASA aerospace engineer Karen Jackson, one of the driving minds behind the project, said of the technology that she'd 'like to think the research we're doing is going to end up in airframes and will potentially save lives.'

Right now, though, things are still very early. The test you see in the video above is of a helicopter falling rather gently from a height of 35 feet. Even still, the dummies inside didn't look so stressed out after it. Wait — do crash dummies ever show signs of stress?

[DVICE via CNET]