There is no good reason for the truth to be suppresed, whatever it is.
If it's terrorism, the government will use it to strengthen the international coalition against terrorists.
If it's an accident, AA/GE/Airbus will want to correct the problem so that this doesn't happen again.
Also, the NTSB is widely regarded for it's independence. And, Airbus's team from France is coming, so in addition to the NTSB and AA, the international team from Airbus should also help keep people honest.
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