Served temporarily as Commanding Officer (CO) of Canterbury Mounted Rifles during WWI.

Served as Assistant Adjutant and Quartermaster General (AA & QMG) at Australia & New Zealand Mounted Division Headquarters during WWI.

Seconded to 61 (British) Division, 1918.

Principal of Flock House School, Bulls, 1930-35.

Commandant of Waiouru Military Camp, 1941-45.

Powles' horse, Bess (Zelma), was a thoroughbred whose sire was Sarazen and Dam Miss Jury. Bess was bred by Mr ADM McMaster of Matawhero, Wairarapa and presented to Colonel Powles by the people of the Wairarapa. She served with Powles in Egypt (1915), Sinai (1916), Palestine(1917), France(1918), Germany (1919), where she marched through the streets of Berlin in the Victory Parade, and England (1920). She returned to NZ in 1922 and after a short time in Trentham Camp was taken to Motukowhai in the Rangitikei. There long-time friends of the Powleses grazed her and put her to stud. She produced around six foals, two of whom were ridden at Flock House. The Powles family also occasionally rode Bess and so it was that one day in 1934, when returning from an excursion around the farm with Col Powles, Bess suffered a cerebral haemorrhage, fell over, and died. She was 24. Bess was the only Main Body horse to return to New Zealand. The others were banned from returning. Two monuments are erected to Bess: the first was erected by Col. Powles and stands in a field of lupin near Flock House in the Manawatu. On the reverse side of the monument is a piece of of marble with an Arabic inscription that means "In the name of the Most High God.' The second monument was originally erected in Port Said in 1932. Bess is one of two horses on a statue to commemorate the Anzac mounted troops. After sustaining damage during the 1956 Suez Crisis, it was re-erected at Albany, Western Australia. AWMM