Drift re-analysed using a simple approach
The Drift Group did their analysis by calibrating their models to things like the drift buoys etc which were drogued relatively shallow compared to a deep ocean but relatively deep when compared to floating debris. If we just take the first 22 bodies (due to their improved consistency relative to other items and not too much time from the impact), calibrate the model to the pollution spot (or slick) and using a method of least squares (Excel) force the curves to go through this point then the potential point of impact extrapolates to 30.51W 2.62N.
(This is achieved by changing time to slick time and using a grid centred on the slick to force the curve through this origin, then converting back from slick time and slick co-ordinates ie using a slick method
). The items in the analysis that appear furthest from the ‘true body line’ (when all items are considered) are the first sightings by the merchant vessel then by the navy. Also the VS recovery position and then (to a lesser extent) its sighting position. The first 2 bodies are also slightly north of the ‘expectation’.
These bodies show a spreading out in an ever increasing wide ‘triangle’ (over this180 hours) from the extrapolated impact focal point as they head north which would be expected due to ‘randomness’. There is also a very slight ‘general’ easterly drift. The bodies are found with very little northerly spread (at one time period) but both this northerly and the easterly trends may not be statistically relevant and may simply be the way the retrieval was done considering only 10% of the bodies were recovered.
So IMO the slick is statistically relevant and its position is useful.
regards. Ian