William Chiles, who has led global offshore helicopter services company Bristow Group for the last decade, will retire effective July 31 and be replaced by current CFO Jonathan Baliff. Chiles will remain as a consultant to the company through 2016. During Chiles’s tenure, Bristow grew rapidly and posted record profits. Baliff, who held senior positions at NRG Energy and Credit Suisse before joining Bristow in 2010, is a former USAF pilot with degrees in aerospace engineering and international relations.