A 10-year veteran of the ADF, he is an expert rifleman who has served in Timor Leste twice, Iraq and Afghanistan.

The Farsi speaker, who also led a combined reconnaissance and sniper team working with the US Marines in South Korea in 2014, said he had always intended to train as an officer.

"But I wanted to do a few years in the regular army [as an enlisted soldier] to see what it was like from the ground up," he said.

Under Officer Tyler Bosch, the Queen's Medal winner at Tuesday's graduation, is one of three brothers currently training to become officers in the ADF.

The Queen's Medal is awarded to the leading student in the graduating class.

Under Officer Bosch said he had been inspired to join the military by the example of his grandfather, Stan Hornby, who had been a member of the Rhodesian SAS before going on to serve in the South African special forces.

"Duntroon is a great pathway to leading Australian troops," he said. "It is a privilege to have that opportunity".

Tuesday's parade was the last to be attended in their current capacities by Duntroon Commandant Brigadier Dianne Gallasch, and Regimental Sergeant Major Warrant Officer Paul Bodsworth.

Brigadier Gallasch, the first female commandant in the 104-year history of the RMC, was appointed in mid-2013. She replaced Brigadier David Luhrs.

Warrant Officer Bodsworth, who has been in the army for 31 years, was awarded the Order of Australia medal in 2012.

Governor-General Sir Peter Cosgrove, himself a Duntroon graduate, Vietnam veteran and former chief of defence force from 2002 to 2005, said the latest class of 151 officer cadets was the 127th to graduate since the college was founded in 1911.

He said the college had graduated almost 9500 officers, nearly 1000 of whom had been women.

Vice-regal and former vice-regal representatives were thick on the ground on Wednesday with former governor-general Major-General Michael Jeffery and NSW Governor General David Hurley also in attendance.

Both men are also graduates of the Royal Military College.

Senior Under Officer Hocking, who was also the parade commander, said it had been particularly challenging to do the rigorous Duntroon course as a husband and a father.

He and his wife Isis have a two-year--old son, also named Ernest, who has spent much of his early life in the shadow of the RMC.

Senior Under Officer Hocking, who was to receive his lieutenant's pips at the graduation ball on Tuesday night, has been allocated to the Australian Intelligence Corps.

Under Officer Bosch, who entered the Australian Defence Academy in 2012, is to return to the academy in 2016 to complete his engineering degree.