The Annex to the report outlines the difficulties that the various organisations participating in the phase 1 and 2 searches had in backtracking the drift (set & leeway) for the Vertical Stabilizer. As I have indicated in previous posts, the onset of the North Atlantic Equatorial Counter Current in the suspected crash area has had a major bearing on the position from where the surface debris may have originated.
Notwithstanding, the following organisations calculated debris positions:-
Météo France, Brazilian Meteorological Service, US Navy, and US Coast Guard.
No methodology has been revealed (except that computer modeling was used), but there is obviously major differences in the vectors used. From the BEA report I have reproduced a chart showing the calculated positions, and have overlaid it with data I previously posted to this forum
http://www.pprune.org/5216571-post4476.html
Data in red or yellow has been added by me.
Mine and the Météo France positions are further to the west than the others and outside the prime area of interest. There is 89NM between the most eastern and western positions, but only 7NM in the north / south distribution. An initial investigation was made in the area of the Météo France position to remove any doubts, and the current concentration is centered on 3°10'N 30°25W.
Time will of course reveal how valid any of the positions are.
mm43