The commander of the 2nd ACCS was Lieutenant Colonel Harold Skipton Stacy, who recruited McFadyen. The unit was, in Charles' later recollections, the most efficient of its kind in forward battle areas in WW1. Stacy was a Sydney Hospital surgeon who brought practical experience and the latest methods to bear on the treatment of the wounded in the field. In this he received strong support from the Australian Red Cross. Stacy enlisted specialist personnel and secured resources for the work. McFadyen, who was a soldier, was one of the unit's few non-medical officers and involved in general administration. Casualty clearing stations were located typically at rail heads or transportation hubs in forward areas. Their role was to provide emergency treatment and to move the wounded back to stationary and general hospitals. Because of the static trench warfare that developed in France in the early summer of 1916 the 2nd ACCS became more of a stationary hospital. 'We were established on a Belgian farmer's property at Trois Arbres near Steenwerck alongside the railway from Bailleul to Armentieres. With the aid of engineers and Belgian labourers the field was quickly transformed into a modern operating centre within 10 miles of the front line and less in a few places.' Stacy had arranged for an X-ray plant, technician and engineers from the Sydney Hospital. He set up a workshop that made splints and thigh cases and, eventually, the station was supplied with electric light. The X-ray plant was the first of its kind in any CCS in France. A steam cooker from the Red Cross supplied food. Qualified surgeons and physicians were added. It was 'the showpiece of the Army Corps and there were continual inspections by high-ranking French and British military and medical personnel.' McFadyen recalled that 'Stacy was far too good for the ordinary run of medical officers' and that he returned to Australia 'without proper recognition.' Stacy contracted influenza early in 1917 and applied for release citing financial and family reasons. This was granted and his appointment terminated on 19 July 1917. The unit he had established continued, however. McFadyen was promoted Lieutenant Quartermaster with the 8th Field Ambulance based at Albert Somme, France, in February 1917. He attained the rank of Quartermaster and Honorary Captain in August 1918.
