The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)

The first flight of the Boeing 737 MAX is scheduled between 9-10 a.m. today.

Boeing workers and other spectators watch as a Boeing 737 MAX airplane takes off on its first test flight, Friday, Jan. 29, 2016, in Renton, Wash. (AP Photo/Ted S. Warren)