By Nadine Schimroszik BERLIN (Reuters) – German air taxi startup Volocopter is recruiting Dirk Hoke, former head of the defence and aerospace division at Airbus, to take over as CEO in September. Hoke will succeed long-time Volocopter boss Florian Reuter and will be tasked with successfully completing the certification process for the company’s electric flying taxis. “It’s going to be an incredibly exciting but also difficult time,” Hoke told Reuters on Tuesday. The executive, like Reuter, worked at Siemens before joining Airbus. Volocopter is in a costly race with companies around the world i…