How effective are avalanche airbags?

From what I've read about the recent double fatality in the Teanaway area both of the riders that died had deployed their airbags.  It will be interesting to see the full NWAC accident report.

A post in Snowest states the same.
Here are a couple of quotes with names redacted in case they aren't yet public.

"name withheld was buried way down like 15' with a bag on and deployed"

"name withheld had a bca 32 pack on and it COMPLETELY ripped the air bag off the AVY pack and he was buried and down a few feet with the empty avy pack attached to him"

Wow. Debris 15' deep (or deeper) indicates a massive avalanche - D3-4.

So much for airbags "being at the top of preventing morbidity,"  or it being the next best thing to staying at home... These were horrific tragedies and my heart goes out to their families and loved ones.

I think it's worth pondering how the use of airbags may make one feel more invincible--less prone to morbidity--and how this may lead us to put ourselves in a situation we may otherwise not be in.
And if so, it would seem the whole airbag thing is working counter to its stated intention of increased safety...

Mostly these fatalities seem to be related to inexperienced people not knowing as much as they think they do about where to be (or not) in dangerous conditions....back to terrain choice, obviously. Airbag seems to have little to do with it. The 'bilers we're parked in a runout, no? Ignorance of the potential danger.

Good point. It's presumably hard to float when the ipile just comes down onto you.

Wow. Debris 15' deep (or deeper) indicates a massive avalanche - D3-4.

The images on Snowest suggest that terrain-trap amplification of burial depth was possible. NWAC is calling it D2.5 in the short statement on the accident page .