Critically, he is not going to jail for intentionally crashing the plane. He is being jailed "for obstructing a federal investigation by deliberately destroying the wreckage of an airplane." Had he cooperated, it's plausible to see him getting away with a license revocation and fine. Instead he did this: "In the weeks following the plane crash, Jacob lied to investigators that he did not know the wreckage’s location.…
Zero incentive to trust such a statement. It's backed by nothing.