Brace upright?
I fly an aircraft with airbags in the front and have asked this question of the aircraft manufacturer and their reply was "don't know".
However, if you look on the Amsafe website it shows the dummy sitting upright, arms at the sides, with the airbag deploying in front between the dash and the person.
I think if you were leaning forward the airbag might hit you in the face.
It seems logical to me for Amsafe to assume that the person would be upright, as would be the case with the pilot controlling the airplane (as implied by the Amsafe videos).
And the seatbelts are inertia reel, which clearly stop/reduce forward motion as well.
Overall it seems to me in the aircraft that I fly that injury is most likely to come from hitting the dash parts (or vice versa), as it is rapid forward deceleration that is most likely to occur in the event of a crash.
So I tell my pax to adopt the following brace position:
- bolt upright, with their back and head hard against the seat back (stiff as possible)
- arms at their sides, braced as far as possible to help keep upright.
It seems to me that the possible drawback with this is that the head is higher and therefore nearer the top edge of the cockpit, which could be an issue if you flip upside down, depending how strong the cockpit ceiling is.
(Although the Amsafe website does show a few video reconstructions of airplanes cartwheeling and landing upside down, with no head injuries.)
Anyway, I guess you have to make your own judgement on this.