I was going to admonish you for not adding your comment in the old thread, but now I see that the old one is closed...  It used to be that old threads could be "revived" with new comments.  Thanks for giving the link to the old thread so that I can see the context.

Aviationengr,  

I wouldn't try to duke it out on who's right or wrong.  Opinions (and that's what they are: opinions) will vary on the use of belts, harnesses, and air bags, just like they do in automobiles.  At the current state of the art of the FAR's JAR's and CAR's, they all read like the airbag doesn't exist, and use of shoulder harnesses is specified in certain conditions.  No "alternate means of compliance" is given and you would have to negotiate that with the local airworthiness authorities on a case-by-case basis.  

correction: newer FAR 25 refers to an "energy absorbing rest" which is broad enough that you might make an argument that the airbag enhances the function of the "rest".

Field experience, even in military operations, could be helpful, if you can get access to carefully collected accident and injury data.  The onus will still be on you to prove that the air bag provides an equal or greater level of safety in the aircraft you propose to install it in.

Basically you need a customer who is willing to pay for this whole process of certification because they are personally convinced it offers them added protection.  Who is right and who is wrong may be decided by who is willing to pay for the answer!  

Sorry, that sounds cynical.  I haven't done a STC search, so maybe there already are some approved examples.  I was recently given a demonstration of a helicopter seat-and-harness system at the HAI Heli-Expo which solves the helicopter pilot's shoulder harness problem when they are long-lining.  Typically pilots can't wear the shoulder harness because they have to lean out the window to see down.  The modified seat permits keeping the harness on in that posture.  This solution addresses a long-standing concern expressed by the Transportation Safety Board.  They have been investigating fatalities in dozens of long-line helicopter accidents where the pilot was not wearing the shoulder harness.

Good luck, if you are pursuing certification of such a product.  Many of us would be interested in learning if such a product could become successful.
 

Steven Fahey, CET

I appreciate your comments but only crew chiefs hang out the windows of Army helicopters.  The CABS was designed for the front seaters.  It's primary purpose is to prevent secondary head strike in the cockpit.

"...only crew chiefs hang out the windows of Army helicopter..."

I don't think you understood what I meant.  See the attached file.

 

Steven Fahey, CET

• http://files.engineering.com/getfile.aspx?folder=8f511b2a-3ce7-44fe-9fe3-02

"...only crew chiefs hang out the windows of Army helicopter..."

yeah, hanging on a M-60

Yes, heli-logging.