Transcript for No survivors in Ethiopian Airlines crash

mystery swirling around a deadly plane crash overseas. The Boeing 737 crashing minutes after takeoff in Ethiopia. 157 people were onboard the flight, and there were no survivors. The pilot reporting difficulties, and had just asked to return to the airport. The U.S. State department confirming several Americans among the victims. The U.N. Secretary general says about a dozen personnel were also killed. This is the second air disaster with this type of plane in the last six months. Here's David Kerley. Reporter: U.S. Investigators are racing to this crash site of another brand-new Boeing 737 max 8. Eight Americans among the 157 killed, among many aid workers. We're very, very saddened. Our heart is broken for this tragic accident. Reporter: The airline CEO visiting the site. The jet taking off this morning for Kenya, when there was trouble almost immediately. The pilot mentioned he had difficulty, and wanted to return. Reporter: The data shows the pilots were having trouble controlling the aircraft. After that call, just six minutes after takeoff, just more than 1,000 feet off the ground, the data stops. That would suggest an in-flight explosion or maybe a fire. Reporter: In October, another new 737 crashed in Indonesia. In that case, the pilots failed to disengage the autopilot. Now, two crashes of this new jet in service for less than two years. There's nothing that would lend any credence about being concerned about these two airplanes. These two crashes are wildly dissimilar. Reporter: Humanitarian and aid groups around the world are grieving the loss of staff who were killed in the crash. Joeanne Toole, going to a conference. Staff from five U.N. Affiliated programs, lost. David, we heard from our expert who says there's no reason to think there's something wrong with this type of plane. But both of these happening back-to-back, and on new airplanes? Reporter: There are more than 70 being flown right now. Airlines they they remain confident about this type of aircraft. It's very early in this investigation. We'll learn more in the coming days. Tom? David, thank you. Back at home, the emergency landing at JFK in New York.

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