NASA risks then saves lives of dummies in helicopters with external airbags
By Tim Stevens 
posted December 10th 2009 9:26AM
posted December 10th 2009 9:26AM
posted December 10th 2009 9:26AM
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saving lives of non-existent beings....
@Billy to be able to save yours later.
I like non-existent beings, they never bother me, they are alright, except when they get god status, then they become a right pest.
What? No video?
WOW, water in space, saving heli crashes...all thats left is curing cancer.
@versionII
I think they are also working on trying to convince people the Global Warming is not a hoax.
"if you're not traveling downward at more than 48 feet per second, anyway"
48 feet per second sounds rather close to terminal velocity. I'm terrible with math so somebody may want to correct me.
@Tidal
48 Feet per second X 3600 second per hour = 172,800 feet per hour
172,800 feet per hour / 5280 feet per mile = 32.72727 Mile per hour
rather pedestrian
@Russe77 Thanks for the math. I passed physics in college, but I also cheated :)
for everyone who don't use mph:
32.72727 mph = 52.6694356 km/h
@Tidal
180 ft./sec is the approximate terminal velocity of a falling human. Not sure what a falling helo's TV would be.
"Dummies?" They prefer to be called "artificial Americans."
@Joseph L Flatley
Why can't I mod your post up?? Cause it needs it!
Kevlar, eh? So let's say you crash into the side of a mountain in a helicopter. How long to the bags stay inflatable? Can you bounce down the slope, turning what should've been the end of your life into an amusement park thrill ride?
Also, I'd be interested to know what average speed a helicopter which crashes from, say, power failure, hits the ground at, because I was under the impression that the rotors slow down the aircraft on its way to the ground.
@Ryan Trevisol
Indeed the rotors slow down and from what I understand you can land safely.. The only time I see any use for this if the engine stopped and froze the rotors, and if that would happen I dont think some airbags would slow that thing enough to save any lifes.
@Ryan Trevisol The rotors do slow it down. It's called auto rotation. You have to set the rotor in a position that the upward wind from falling is able to turn the rotors to enable enough lift to slow your decent.
Disclaimer: I have only done this with RC Helicopters...
@Snelpiller You'd would want this any time your engine, transmission, or tail rotor fails and you are flying too low and slow to perform a proper autorotation. The idea is to keep your main rotor spinning at the same speed. If you can't quite manage that because you don't have the time to recover before you land, then that is probably where these airbags come in.
terminal velocity is about 115mph (about 169 ft/sec)
@t2af That makes no sense. Terminal velocity for a feather is much slower than it is for a missile. You need to specify the object you are talking about. Terminal velocity refers to the speed at which an object falling from the sky through our atmosphere (or water, depending on the subject) stops accelerating and maintains a constant speed.
@holstein13
http://www.grc.nasa.gov/WWW/K-12/airplane/termv.html
Look up:
http://en.wikipedia.org/wiki/Autorotation
Helicopter will only fall at close to terminal velocity when the pilot cannot control the angle of the blades anymore. If the motor shuts down -> they can land relatively safely using autorotation from any height. Knowing how to do autorotation is included in getting your pilot's license. Every helicopter pilot has to be able to do it.
@Ernesti
The longest autorotation in history was performed by Jean Boulet in 1972 when he reached a record altitude of 12,440m (40,814 ft) in an Aérospatiale Lama. Because of a −63°C temperature at that altitude, the engine flamed out and could not be restarted as soon as he reduced power. By using autorotation he was able to land the aircraft safely to the ground.[citation needed]
Cute but was the shortest? Without dying.
@Wwhat
plus, this relys in the pilot being still alive.
@Wwhat Auto-rotation requires a minimum safe altitude before it works, you need enough height to get the rotor spinning fast enough for the flair out before impact. So like terminal velocity, it depends on the heli. The one in the image above probably won't need as much altitude as say a Chinook.
"The helicopter and its simulant occupants were said to be largely undamaged, giving hope that such a system could reduce injuries"
Yeah right! The dummy sitting in the rear left seat lost his head! I'd say that's pretty damaged...
This system would be most effective when helicopters have problems just after take of or just before landing, when out of translational lift. Other problems aside if you've got a helicopter into a good auto this could potentially cause more damage (i.e. increase the chance of roll over) to what would otherwise be a very nice unpowered landing, no?
@NoBox Don't forget the hours of low-level hovering that some helis do.
When are we gonna get the Electron-Aircapsule like Halo Drop Troopers have in the videogame? That's when I will be stoked!
Video or it didn't happen!
I'm pretty sure the dummy in the back is missing a head and an arm...