Well we don't know all the facts surrounding this incident, however---IF, as has been posted here the engineer was not seated and "down the back" then complacent is hardly the correct term----stupid, incompetent or just plain inept----take your pick---the salient fact is he / she should not have been anywhere else other than in the seat and monitoring the tow----as I say, my comments are based purely on the information provided on this site and, should demonstrable proof emerge that his / her abscence from the seat was not a prime causal factor then I will apologise and retract my comments. Until then however, I rest my case.