Air Traffic Audio Reveals Urgent Warning Moments Before D.C. Plane Crash

Extremely tense audio reveals air traffic controllers warned the U.S. Army helicopter that fatally crashed into an American Airlines passenger plane in Washington D.C. Wednesday night moments before the catastrophe.

With escalating urgency, the control tower asks ... "PAT25, do you have the CRJ in sight?" and instructs the military Black Hawk helicopter to "pass behind" the aircraft. The warning came about 30 seconds before American Airlines Flight 5342 -- a CRJ 700 -- collided with the chopper in mid-air near Reagan Washington National Airport.

The collision sent both aircraft crashing into the icy Potomac River ... with no survivors expected. There were 64 people on the American Airlines plane ... including four crew members. Three soldiers were on board the Black Hawk helicopter. At least 30 bodies have been pulled from the river, and the rescue mission is still underway.

U.S. Transportation Secretary Sean Duffy says both flight paths for the aircraft were usual and standard ... "something went wrong."

Eyewitnesses have shared how shocked the area is by the disaster ... with many noting the stunning explosion happened in an instant and momentarily lit up the sky.

The American Airlines flight took off from Wichita, Kansas Wednesday night and was descending to Reagan National when it was tragically hit. Among the passengers were U.S. Figure Skating team members, world champions and coaches.

American Airlines sources confirm to TMZ that the company is flying the victims' family members out to D.C. for free ... and will pay for lodging, food, and will help in any way possible as so many grapple with this devastating loss. They are also working with special care teams trained to handle crisis situations.