Kandahar air base, southern Afghanistan. The NATO forces stationed here include the US, Britain, the Netherlands and Australia. They fly constant combat missions to support troops in the isolated forward bases and to attack the Taliban. REPORTER: With many roads in southern Afghanistan too dangerous for NATO troops to travel, these helicopters form an integral part of a strategy that's seen NATO place troops in areas where there's been no foreign presence since the US takeover in 2001. The sprawling Kandahar base is central to holding the south of Afghanistan. Even inside this vast compound there are dangers. A rocket recently hit this accommodation block housing Australians, wounding three. There are 110 Australians flying and maintaining the two Australian army Chinook helicopters that operate out of here. They regularly fly to forward LZs - landing zones - to get troops in and out, even under fire. Lieutenant Colonel Mick Prichter is their commander. LIEUTENANT COLONEL MICK PRICHTER, ADF: I have to say it certainly hasn't been since the Vietnam War when Australian army aviators have flown into what we call hot LZ, where they've been engaged by enemy forces as they approach the LZ. There's been times when we've had to go in and extract friendly troops out of an LZ and they've been under fire as well. There's mountains, weather, fog, snow and dust so when they go in to land they tend to be enveloped in a cloud of either snow or dust depending on the time of year. And then there's the threat from the anti-coalition militias. Enemy forces have engaged our helicopters with machine guns and rocket-propelled grenades. That can happen at any time. Most of the helicopter losses, particularly in the early days of operations in Afghanistan, were lost during dust landings at high altitude. What happens on a dust landing is, as the aircraft gets close to the ground, it's a downwash, so its rotor downwash begins to stir up the dust and so the last 30 or 40 feet of the landing the pilots may well lose all visibility prior to touching the ground. And it's a dangerous situation to be in. Two weeks after I flew on the Chinooks, an American one came down in exactly the same area where we had been. 8 US soldiers were killed, and 14 wounded. Mechanical failure was blamed, but the Taliban claimed to have shot it down with a ground to air missile. The US special forces on board were on their way home. LIEUTENANT COLONEL MICK PRICHTER: We have a range of technological solutions on the aircraft that help us to defend against those missiles. We also employ tactics that really do preclude us being engaged by those missiles most of the time. In the '80s when the USSR was struggling to control Afghanistan, the US provided the Afghan Mujihadeen with Stinger and Blowpipe shoulder-fired missiles, which they used with devastating effect against the Russian helicopters. When the Russians left, the CIA tried to buy back the thousands of unused missiles in Afghanistan. But they only recovered a fraction, and the fear now is that missiles have inevitably found their way into the hands of the Taliban and al-Qa'ida. This footage, shot by an SBS cameraman just recently, shows a missile just missing one of the Australian helicopters. At least one US Chinook in Afghanistan - shown here - has been confirmed as shot down, killing all on board. In Iraq in January and February eight US helicopters have been shot down - more than ever before. US command is seriously concerned about the presence of missiles in both Iraq and Afghanistan. The Australians Chinooks are, they say, the best armoured - and the best armed. SOLDIER: Puts out around 3,000 rounds a minute. They're also good for reliability - they just keep going and going and going. REPORTER: So they've been getting a bit of usage lately? SOLDIER: Yeah. they've been used, yep, yep. Very effective, very effective. The gunners left and right have got armour up to the waist left and right and for doing deliberate action or carriage of special persons we ballistic the whole floor. Normally we carry floor armour as well. That's up to here. REPORTER: So you're saying it's better armoured than the American and the British ones. SOLDIER: Very much better armoured. I'm on board one of the Australian Chinooks for a 6-hour mission to some of the most dangerous and inaccessible bases in Afghanistan. In the darkness their night vision and technological superiority gives them an edge over the Taliban. The two Australian helicopters are escorted by US Black Hawk helicopters. I take that to be a good sign. If they were expecting trouble they would be using the more heavily armed Apaches. Shortly after we take off there is an alarm. Fortunately, it was a false one. The guns are loaded and tested. After a long, cold flight through snow-covered mountains and a refuel stop we arrive at the US Special Forces outpost. These troops are part of the 12,000 under direct US command. They have been manning small outposts like this since 2001. Small groups of special forces with Afghan soldiers. Their role is to actively hunt out the insurgents. It was how the US tried to control the south before NATO arrived and moved in, in force. The huge amount of Taliban NATO encountered in the last year was a reflection on how ineffective this light footprint strategy was. The next part of the night's mission is to move a group of Romanian troops who are on operation in Zabul province. They are moving to establish a new outpost. But concerns have been raised about the poor state of their ageing eastern bloc equipment - the same as used by the Taliban. Many countries won't allow their troops into such a dangerous area. The expected Taliban offensive in spring will test these new troops in their remote outposts. It's time to head back and the helicopters fly exceedingly close to the ground to avoid missiles and ground fire. But at night another hazard is hitting a mountain. We cross a mountain pass with only metres to spare. The rear loader almost falls out in the unexpected turbulence. As we approach Kandahar, flares are fired to redirect any heat-seeking missiles away from the helicopter. SOLDIER: It's a magnificent country. It's a beautiful place to be. It's so rugged that it is beautiful. It's very, very challenging as far as the flying goes. It makes it a tough day out for us and it gets even harder by night. These two Australian Chinooks, and the soldiers that fly and maintain them, are back in Australia but already people within NATO are asking for them to be replaced with more Australians, and NATO commanders are saying this war will take 10 years to win.