Hi Tech,
Thanks for bringing out bringing out safety points. The differential pressure in Fan cowling is a good point. I suggest the cowling be made of Titanium:
1) With titanium protracted turn around inspection is not required
2) Engineers can stand on the cowling.
3) Engine aerodynamic profile will be less bulky.Less drag is created eventual fuel efficiency improvements
4) When sheet metal is bent it improves stress, whereas Composites weakens.
5) It is alarmng to hear this has occured before on other engine.
6) By employing Composites on fan cowling, a few kilograms of weight may be saved, but using Titanium, passenger lives can be saved.
7) I guess FAA is listening