Update - BA 777 crash at LHR

An update from AAIB has been released.http://www.aaib.dft.gov.uk/cms_resources/G...im%20Report.pdfThe main thing I got from it, is that the only thing that can really fit the data is a restriction in fuel flow in the engine prior to the engine-driven HP fuel pump which resulted in a too-low fuel flow into the engines.Causes of this fuel flow restriction are not determined, but the possibility of some blockage, possibly by ice in the fuel system, is the most suspicious. The problem in better defining this is that so far testing and data analysis have been unable to duplicate a blockage caused by ice in fuel. The report does admit a couple of things:unable to exactly recreate the environment in a test configuration (my reading mainly duplicating the temperature experience)some of the flight data suggest that this particular flight's conditions were unusual, when compared to the database of all 777 operations. Thus it is difficult to prove or disprove if the conditions were directly involvedthe state of knowledge concerning aviation turbine fuels with water in certain temperature regimes has gaps, making it difficult to fully understand fuel performance.It looks like AAIB is asking certification agencies to look at the problem of cold weather ops / fuel performance. Included in this is the possible advantage of using icing inhibitor in civil transport turbine fuels.scott s..