The college professor accused of watching porn on a plane has resigned from his position.

Grant Smith, of Cottonwood Heights, Utah, stepped down from his role as a materials science and engineering professor at the University of Utah last month, reported the Deseret News.

As RadarOnline.com previously reported, Smith was arrested last November after he was spotted watching child pornography while he sat in first class on a flight from Salt Lake City to Boston.

Grant Smith was arrested Saturday afternoon after a fellow passenger in the first class cabin of his flight from Salt Lake City to Boston alerted the crew that the man was watching child pornography on his laptop!

Smith, 47, from Cottonwood Heights, Utah, was taken into custody by the Massachusetts State Police at Boston Logan Airport as soon as the Delta flight arrived at 4 pm.

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Smith has been charged with possession of child pornography and other charges are pending, officials told the AP.

Grant's bail was set at $15,000.  He'll be arraigned Monday.

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