PPRuNe Forums - View Single Post - AF 447 Search to resume (part2)
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23rd May 2011, 22:39
Lonewolf_50

Join Date: Aug 2009
Location: Texas
Age: 60
Posts: 5,446
Just to remember: The conditions (mech. damages) of the debris recovered floating seems consistent with a flat spin "heading to RH" (CCW as viewing from top)
I think you said that backwards, or I understood it backwards.

If the aircraft is spinning CCW (and the aircraft is not inverted), its heading keeps changing to the left (being south of the equator would not change that ). Put simply, if we mark the nose of the aircraft each time it passes through 360/North, it's heading will decrease during the next rotation until it arrives again at 360/North, and repeats the decrease on the next rotation.

If you spin/rotate CW, as viewed from above, (I have in my minds eye a fast moving, old fashioned compass card), as we pass through 360/North on each rotation, your heading will increase during the rotation. That's more of a right hand turn.

Exception: Galley "good conditions".
Wasn't that explained earlier as the airframe absorbing most/more of the impact? (Think "crumple zone" in a car collision).
Question 1): Supposing a flat spin in the end. Typically, how many degrees per second? If tail cone separated in flight, was at low height as showed by "concentration" in seabed.
It might be that Airbus never collected those data points in testing.
Question 2): Itīs possible spinning to RH hit the water banking left? And if the VS detaches before impact? LH wing can fall?
"Flat spin" will not by itself rule out a bit of roll along the longitudinal axis during the spin. The amount depends on aircraft type. The type I am familiar with had some (small) nose roll/oscillations in an erect spin. (Grateful I've never been in a flat spin, I understand it's a horror show.)

It also depends on the coupling between vertical stab and wings, which again would depend on a particular aircraft's unique characteristics.

I'll leave to those who are familiar with big jet/passenger jet spin and upset characteristics to explain in detail.