What is a twin-engined helo allowed to do that a single isn't?
I'm a fixed-wing guy but someone has just asked a question to which I can't instantly find an answer.
A business needs a helo to fly directors to site meetings in Western Europe (primarily UK, France and Ireland), they think they need a twin but are being challenged that this is too extravagant and a single would be OK. Where can I/they find a definitive statement on the single-engine restrictions that would not be relevant with a twin?
HFD