Another thought is ice, even though he wasn't airborne for very long. I thought I saw a post earlier showing the surface temp at departure was +1 and the dewpoint was -2 with mist.
I would think he should have been taxing with the engine anti-ice on and that he would turn on the wing anti-ice just after gear retraction. He was climbing through cold moist air over the lake and the temp at 3,000 AGL should have been about -5. Sometimes ice can accrete rapidly in cloud layers. If he forgot the anti-ice, ice on an intake could have damaged an engine or, more likely, ice on the leading edges could have increased his stall speed in the climbing turn.
Last edited by Murexway; 1st Jan 2017 at 13:25.