delivered to NAC for operation by Irish airline Stobart Air on 14 June 2016; that same year, ATR delivered the first ever ATR 72-600 High Capacity aircraft (78 seats) to Cebu Pacific. In October 2016, Christian Scherer was appointed CEO. In 2017, ATR celebrated its 35th anniversary. On 1 February, ATR and Sweden's BRA performed the first ATR biofuel flight. During August 2017, US regional carrier Silver Airways signed a letter of intent for up to 50 ATR 42, a return in the continental US market since 1997 when American Airlines converted 12 ATR 72 options, due to the rise of regional jets and the American Eagle Flight 4184 crash in 1994. ATR lowered its output to 80 deliveries a year from 2017 and boasts a nearly three-year backlog after FedEx Express' November 2017 order. In 2017, ATR booked 113 firm orders and 40 options, and delivered 80 aircraft: 70 new ATR 72-600s, 8 new ATR 42-600s and 2 second hand ATRs. By April 2018, the fleet was flying more than 5,000 times per day and had operated 30 million flight hours. By the end of June 2018, Leonardo S.p.A. had shipped the 1,500th ATR fuselage while nearly 1,700 airliners had been ordered; ATR reportedly led the turboprop regional airliner market since 2010 with a 75% share. The company's aircraft were being operated in nearly 100 countries by 200 airlines and 30 million flights has been completed; it was also claimed that an ATR airliner takes off or lands every 8 seconds. On 13 September, Scherer left its CEO role to replace Eric Schulz as Airbus' Chief Commercial Officer. ATR replaced Scherer as its chief executive with Stefano Bortoli, president of ATR's board and Leonardo aircraft's senior vice-president for strategy and marketing. At the end of October, the 1,500th ATR was delivered, an ATR 72-600 to Japan Air Commuter, after nearly 500 ATR 42s and more than 1,000 ATR 72s deliveries to over 200 operators in 100 countries. During 2018, ATR delivered 76 aircraft; the rate of production has held at a stable rate. The company opted to pursue a low-risk strategy, avoiding disruptive measures while opting to integrate relatively straightforward enhancements onto its aircraft, such as the Elbit Systems ClearVision wearable enhanced vision system. 2020s In May 2022, ATR started studying an Evo hybrid-electric variant, aiming for a 2023 launch and service entry before 2030. An optimized turboprop running