Complex sentence: The firm has commissioned artists for nose art projects, for example in 2011 the street artist Retna was commissioned to graffiti the tail of the firm's largest corporate jet, a Bombardier Global Express XRS.
Split into simpler sentences: The firm has commissioned artists for nose art projects. In 2011 the street artist Retna was commissioned to graffiti the tail of the firm's largest corporate jet, a Bombardier Global Express XRS.