Transcript shows pilots warned of danger several times in seconds before crash . The plane was flying from the U.S. to Mexico when it crashed into a mountain near San Luis Potosi, Mexico, on Friday afternoon. Delegation headed to Russia for 70th anniversary of massacre of Polish prisoners of war in World War II .
Transcript shows pilots warned of danger several times in seconds before crash . April 10 crash killed Polish President Lech Kaczynski and about 100 others . Delegation headed to Russia for 70th anniversary of massacre of Polish prisoners of war in World War II .