Cabin space is an important point. The 189 is advertised as being slightly bigger but does it have the capacity to carry a Mountain Rescue Team with all of its equipment or to rescue a dozen mariners from a liferaft 150 miles offshore? These must be basic requirements for a SAR helicopter operating in the UK, as must the ability to do the same at night. It's not that long ago that a declared SAR asset in the UK was unable to rescue the survivors of a helicopter ditching in the North Sea in poor visibility because of crew and aircraft limitations. So have the previous night overwater concerns about its younger brother, the 139, been sorted out and if not, does the 189 have different design features to overcome those problems?