At a time when four engine aircraft were still relatively rare, the Heron was well received by flight crews and by passengers who appreciated the additional safety when operating into more remote locations. Some 150 were built and exported to around 30 countries. Later, a number of Herons were fitted with 290 hp (216 kW) Lycoming IO-540 flat-six piston engines.The modifications were carried out by the Riley Turbostream Corporation of the USA and so became known as the Riley Heron. Due to clutter it was difficult to get a nice side on shot but this view shows the flat engine conversion nicely.