According to the Jerusalem Post, if a bomb knocked Airbus A321 out of the sky, that would challenge Egypt’s assertions that it had brought under control militants operating in the Sinai Peninsula.
Source: The ISIS affiliate in Sinai that is eluding Egypt’s security dragnet – Middle East – Jerusalem Post
This is an insightful article into the terrorists that operate in Sinai. What is most worrying is that this sort of model could easily be exported and provide a wider threat. The Sinai terrorists operate in small virtually invisible cells.