The sun isn't yet up but Major Patrick Hoare, Officer Commanding Bravo Company, 1st Battalion, the Royal Australian Regiment (1RAR), is already hoping for rain.
In Lae, in north-eastern Papua New Guinea (PNG), where he is about to signal the start of a seven-kilometre patrol through jungle and farmland on the fringes of the city, daytime temperatures have been consistently above 30 degrees, with humidity as high as 80 per cent.
As luck would have it, it is drizzling as his combined force of about 120 Australian Defence Force (ADF) and Papua New Guinea Defence Force (PNGDF) soldiers begins snaking its way through the forward operating base front gate.
It is day three of Exercise Wantok Warrior, and the tempo for the two-week infantry-focused combined training exercise is ratcheting up.
The integrated force is preparing to conduct an air-mobile assault drill on the city's airport precinct, using CH-47F Chinooks from the 5th Aviation Regiment to overwhelm the aptly named Northern Allied Defensive Zone Air Base.
The energy-sapping patrol will end with a demanding urban clearance at a shuttered former teaching college.
As well as working with the Chinooks, training scenarios will include dismounted assaults, security and stability activities, small boat landings and defensive operations to secure critical infrastructure.
The overarching aim is to build interoperability between the troops, with each serial designed to also hone individual skills.
Closed in 2015, the only lesson being taught in Lae's former Telikom Training College is the deadly art of urban warfare within the two-storey maze of partially boarded-up classrooms, interlinked offices and engineering workshops.
'Lots of booby traps and people hidden in sneaky little corners. Definitely full of surprises.'
With the PNGDF's 1st Royal Pacific Islands Regiment (1RPIR) Alpha Company providing support by fire, 1RAR soldiers conduct a bounding clearance, but it is not going all their way.
A fire team from Townsville's 3rd Combat Engineer Regiment (3CER), acting as 'Red Force', has had several days to develop concealed firing positions and plant improvised explosive devices throughout the derelict buildings.
"You're dead," says 3CER's Captain Christopher Kiel-Chisholm, acting as an adjudicator, after a soldier charges down a passageway and into a trip wire.
Corporal Jordan Hunter, an acting troop sergeant with 3CER, later explains that the 'eyes-up' focus on the enemy means the explosive risk often goes undetected.
"It's easy to get in that tunnel vision," Corporal Hunter said.
"We do training like this to give infantry and other call signs more situational awareness that, during assaults, it's not only the shoot threat, but there's also an explosives hazard that's just as important."
Corporal Riley Pickersgill, of 1RAR, was among those to embrace the realistic inner-city setting.
"It's a 360-degree environment, so you can have people shooting at you from every which way - up, down, left, right - there's a lot more to think about than someone to my direct front," Corporal Pickersgill said.
"Lots of booby traps and people hidden in sneaky little corners. Definitely full of surprises. We have junior members here probably having their first time doing this."
Major Hoare, the Australian Contingent Commander for Wantok Warrior, said he was eager to see how the 30 to 40 new members of Bravo Company handled the test.
"It's important to understand the improvised explosive device threat and how significant and traumatic the casualties can be if we don't do our drills properly," Major Hoare said.
"I think it was sufficiently realistic and challenging for our guys and we met many of our key training objectives as well as, again, integrating with the PNGDF and sharing that experience with them."
