Slip and Turn
The cowl latches were most likely closed, that is why no one picked up the fact that they were not engaged.
The reason for them being latched is that once they are disengaged and the cowl is opened to enable engine work to be done the catches hang down, if you catch your head on one of these usually it hurts a lot and requires the use of lots of industrial language. To avoid the chance of injury the catches are latched back into the closed position when work is taking place.
The cowls were the closed without opening the latches and engaging the hooks and re latching them.
I'm sure that if the latches had been in the unlatched position some one would have spotted this error.
Last edited by A and C; 4th Jun 2013 at 15:24.