A New Jersey man accused of engaging in sexual activity with a 15-year-old girl on his private airplane after he set it on autopilot has been sentenced to seven years in prison.

Fifty-three-year-old Stephen Bradley Mell, a former CEO of a New Jersey investment firm, was sentenced Monday in federal court.

The Far Hills resident had previously pleaded guilty to charges of interstate travel to engage in illicit sexual conduct and receipt of child pornography. Authorities said he had also received nude images of the girl.

Mell's legal team argued before Monday's sentencing that Mell had fallen into "a spiral of depression" brought on by survivor's guilt because he had given up his seat on a helicopter that crashed, killing his friends on board.