That said, more than a third of departures yesterday were "off-track" (i.e. radar tracking revealed that they were not following the NPRs).[/QUOTE]
Thanks Dave. It's interesting that some northbound 09L departures are off the NPR track. ATC are permitted to deviate from the NPR above 4000ft but webtrack indicates they are below this altitude when continuing beyond the point where they should have made a left turn. .