From everything I have read I think it was just a simple fire cracker. Nothing that would actually cause the plane to break up. I think this was planned event to get people up in arms and get some agenda passed so we have fewer rights. One step closer to a socialist state.
The Man In Orange:
My wife Lori and I were passengers and innocent victims of Northwest Flight 253 (Flight 253). - What I would like to emphasize in this article is that not only did we almost lose our lives in the air, but we also almost lost our lives after our plane landed. Let me explain. Ref. Source 5
Umar Farouk AbdulMutallab, the Nigerian man accused of trying to detonate an explosive device in his underwear aboard a Christmas 2009 flight to Detroit, pleaded guilty Wednesday.
AbdulMutallab had been indicted on charges including attempted use of a weapon of mass destruction, conspiracy to commit an act of terrorism, and possession of a firearm or destructive device in furtherance of an act of violence.
AbdulMutallab was a passenger on Northwest Airlines flight 253 en route from the Netherlands. After returning from the bathroom, he pulled a blanket over his head, "pushed the plunger on the bomb and prepared to die," Jonathan Tukel, chief of the National Security Unit for the U.S. Attorney's Office in the Eastern District of Michigan, said in opening statements.
U.S. Officials say the terror group al Qaeda in the Arabian Peninsula was behind the alleged bombing attempt. Ref. CNN
Sued over 'underwear bomber'
A New York man is suing Delta Air Lines and Air France-KLM for $US10 million for injuries he says he sustained while helping to stop the so-called "underwear bomber" from blowing up a plane on Christmas Day 2009. Ref. Source 5