The issue is not why the pieces fell off. It's why the runway debris went unreported so long.
Visions of CDG and Concorde ... but that sounds too much like a UK tabloid report.
I guess this will be discussed in any accident/incident report, but what are Jersey's runway inspection procedures? (The most important issue not yet discussed)
Where was the cowling on the runway - to the side, in the grass, in the middle?
How many aircraft departed after the Embraer? (see previous question, suggests that the cowling wasn't in a "dangerous" position).
But even those aside, what about the engineering inspection/supervision, crew inspection before flight? Though I don't think the crew inspection would have changed things here at all unless it was something very obvious and in flight I assume that the missing cowling had no effect (vibrations?)...
Interesting website and article here
Debris Danger and here
FODNews.com Mission
fc101
E145 "Jungle Jet Driver"