I’m in a state of fascination now that I’ve had time to peruse the Arcteryx patent for a battery operated fan-filled avalanche airbag pack. The patent includes juicy tidbits such as the idea of being able to fill the bags up to 50 times between charges, and including a motion switch that could activate the system without user intervention (with cutout, of course, in case you want to do inverted sorts of things on purpose). Perhaps most importantly, the system will weigh significantly less than compressed gas units and be easy for TSA to deal with (though the powerful lithium battery is probably subject to some sort of restriction). View the PDF here, or just check out the images below. Discuss? (Click images to enlarge slightly for more legibility, or peruse the PDF linked above.)

Another drawing from the patent, this one showing more the backpack. Hopefully they'll make the rucksack light as well, so combined with the electric system the whole rig will have an astounding lack of mass for backcountry skiing and other snowsports.

Another view of the proposed system for backcountry avalanche safety. Shape of the bags is optional, any volume can be filled with the blower or so the patent implies.
WildSnow.com publisher emeritus and founder Lou (Louis Dawson) has a 50+ years career in climbing, backcountry skiing and ski mountaineering. He was the first person in history to ski down all 54 Colorado 14,000-foot peaks, has authored numerous books about about backcountry skiing, and has skied from the summit of Denali in Alaska, North America’s highest mountain.
36 comments
CD will have a lot of fun explaining this one to journalists…Google the term “vapor bag” and you’ll find it has a very different meaning, particularly for residents of Colorado and Washington.
I’m a bit sceptical of the volume of air moved by the fan (or inflation speed, whichever you prefer) but otherwise it could (likely will) be a winner.
seems too mechanical, room for equipment failure?
also, the speed the bag is inflated seems like it would be slower than a canister?
got to hand it to them, its original
Jernej, those were my thoughts exactly, it seems like to inflate quickly enough it would need a very large and fast fan, not something light and small.
Are there any specs on CFM that the fan will move or speed until full inflation?
If you’re caught in an avalanche with one of these, I would wonder how much air you’ll pull in, vs how much snow, and what the effect would be on your buoyancy.
Also, I wonder what they’re using for a “motion switch” – With all the forces involved in skiing, I wonder what they’re assuming means that you are in an avalanche.
Also also, I wonder where the intakes would be situated on a pack, and what this would do to the ability to strap things like jackets to the outside of your pack.
Last one – a question that came to mind was this – why don’t we see airbags with multiple chambers? As in, a left, a right, and a center? You’d be able to keep some protection, in case you’re dragged through trees and over rocks which might shred one or more of the chambers.
I was thinking it could be slow to inflate but you could use multiple fans which would also give you some mechanical redundancy.
I’ll take an airbag that inflates a couple seconds slower but saves 4 pounds. This is a game changer IMO…
This looks like a great idea, that could certainly reduce weight and its nice to see them thinking outside the box, but thinking of the physics involved here makes me doubt its possible. I dont want to put them down, but figured id kick off the discussion… So to fill a 100L airbag in 5 seconds as the patent states, would require 1200 LPM of flow. Considering that it will take considerable pressure to push the airbag out of the pack and maintain its pressure while in an avalanche I find it hard to believe that the tiny motor they call out is up to it. A compressed air cylinder is well designed to for this task because its pressure is basically on-demand and does not need to generate additional flow to maintain pressure. Again though great to see them outside the box!
100 liters of fill in between 2 1/2 and 5 seconds. Hard to imagine- I’d love to see it. Curious what their actual airbag volume will be. 100 seems small considering that everyone else uses 150 or 170 liters. They mention 150 liters elsewhere.
I would think they would need to utilize some sort of venturi valve to get that much airflow that quickly, but my untrained eye can’t tell if that’s what’s going on from the diagrams. The compressed gas airbags use a venturi to get the required amount of fill. The actual cylinder provides very little of the final amount of air in the airbag. The rest gets sucked in via the venturi effect.
Greg- ABS uses 2 airbags.
It looks like similar technology to what is used in electric RC EDF jets. They have very small motors that are very powerful. I’m not sure as to how much volume they move per minute but they can certainly push model planes around at very high speeds.
This one is of similar size and power to the one in the patent and puts out 560g of thrust through a ducted fan. http://www.hobbyking.com/hobbyking/store/__10986__Turnigy_2615_EDF_Outrunner_4000kv_for_55_64mm.html
Never mind the physics…way too many moving parts.
seems kind of silly, why not use a gas generator/chemical reaction, similar to a car airbag but with a lower reaction rate….
Eli, that would be the best in my opinion but would not travel well. Air travel is the crux of this whole deal. If something can be made that is legal to put in your luggage, it’ll take the whole market. Lou
Skeptics! Use it, you will see…I have played with 2. I think it was 5-7 seconds to fill up tight. Light pack, so clean and simple. A good step in the right direction. This was a year ago, wonder how much better it has gotten now!
http://www.tsa.gov/traveler-information/parachutes
Parachutists are allowed to carry explosives onto commercial airplanes, why not skiers?
Simply revolutionary.
Very very interesting. I wonder what they’re thinking for pricepoint…
If there is a patent pending. There is a working prototype in some garadge. Price is my big question?
Some eager to brag (grin) Canadians claim to have used or at least seen the protos. If this thing works, it will prove that hockey is not the only thing they’re passionate about (sort of inside joke). Lou
I wonder how the power situation will work out. Not too troubled by moving parts, but battery life in the cold is a perpetual issue. Could imagine something going sideways late in a long day and having the bags flaccidly inflate because the battery is cooked. A hilarious bummer.
Our backcountry devices are headed in a familiar direction. Google “soldier power” to see the future.
It looks like the inside of my shop vac!
Interesting. The diagram indicates 14.8v, 35 amps. That almost 500 watts of power. Assuming good efficiency, it could be in the same ballpark as a shop vac. Someone should hook their shop vac to a garbage bag and test the inflation time.
Battery should not be any big problem. Modern LiPo(Lithium Polymer) batteries can deliver quite a lot of power and store it quite long times, all in rather small and light size also. Monitoring how much battery there is left is quite easy to do with simple electronics.
And also, people mentioned the scepticism about moving parts, well it should be easy to test also if it works or not, currently available systems aren’t perfect either and those are not easy to test, or easy to test but not put back to functional… 🙂
It would be nice to make a practical test, take a hair dryer and 200litre garbage bag for example and see how quickly it fills… Venturi valve could also be tried, should not be that big task… 😀
I think this would work great. Fans that are powerful enough is no problem. Computer fans can push 120m3 of air per hour or more, and those are made to be super silent and small, if noise is not an issue, and it wouldnt be on a pack like this, you could prob get much higher flow rates. Fans usually have just one moving part, and most fans are made to work for thousands of hours, so the fans reliability would not be a problem in it self, but broken wires or connections and battery failure would be my greatest concern. If the pack was equiped with an easy to use automatic diagnosis system where you would just push a button before use and the pack would say aok, or warn you of potential battery problems or other failures, then i think it would be very safe, and maybe even more reliable than a can of air.
The patent speaks about a max. current of 50 A during 10s. This could mean the bag takes 10s to fill, assuming that the motor will need to run at full speed until the bag is full.
I’d say 10s is a rather long time when you’re in an avalanche.
Thanks, this is a wait and see what happens but it will be fun to follow.
Rob, indeed, I’d say 5 seconds would be more like how fast we’d want the bag to inflate, that is unless it can easily finish inflating while being roiled around as the washing machine effect begins and you tumble down the mountain. I kind of have the feeling that inflation time will be hotly debated if and when this sort of airbag comes to market.
According to the data provided in the documents, the Electronic speed controller that controls the motor, can give 10s burst of 50A current and 40A continuous. The motor spec says that motor is most efficient at 35A, so most likely can handle higher currents, at leas for short bursts.
So, if the battery is 4cell LiPo with 14.8V voltage, that gives 14.8V x 50A = 740W power for 10 seconds and 14.8V x 40A = 592Wcontinuous power.
For reference, normal vacuum cleaner is about 1500W, which is optimised probably quite differently, as it needs to create quite strong static pressure(or vacuum actually), and with avalanche bag you most likely want to just move as much air as possible with some static pressure capability to keep the bag inflated.
One interesting thing is also the speed of the engine, the spec says that 5100rpm/volt so with 14,8V it would make some 75 000rpm, which is quite high… 😀
These of course do not tell directly anything about real life performance, but the concept is very interesting and I believe it can be made working also in real life…
I have serious doubts about the air intakes…
As everybody knows, powder snow can stick a lot over every kind of mesh fabrics.
In the event os an Avalanche theres a lot of powder flying around and been atracted to the air intakes on the sides of the backpack…
I think it’s very easy that snow sticks on the air intakes making imposible to the fan to get the air needed to inflate the bagas quickly.
The idea is very interesting and I’ll be very in to see how is developed
Where can I contribute to the kickstarter page?
It’s also going to be reliant on that little flap valve to keep the air inside the airbags whilst they’re being bashed around in a slide.
That being said, if it’s for real and Arcteryx are going to sell it, we can be pretty sure it will have been tried in a slide or two, strapped to a dummy, so it will probably work.
Hi Lou,
Do you know any news about that system?
Rumor that I can verify as fact is we will definitely see something soon from a certain company that’s not necessarily Arcteryx, and full story at Winter OR show. Watch this space. Lou
I always keep looking!
Thanks Lou!
I’ve seen a demo of the black diamond jetforce and these things look really exciting. The jetforce goes to full inflation in 3 seconds and then the fan has to maintain the pressure for three minutes to meet CE standards. The cool thing about the fan is it can keep pumping air into the bag even if it gets punctured with up to a 7 inch gash. That’s more than can be said for traditional systems. Also interesting is that traditional systems with canisters still draw air in(venturi valves) as they inflate so they are as vulnerable to blockages and snow still has air in it, so as long as the system can keep pumping, a bit of snow in the system is fine (they do have advanced filters though).
In fact, this very site has a demo of it: http://www.wildsnow.com/10670/jetforce-black-diamond-avalanche-airbag/
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