Crossing the aerial bridge

But the operation would not be possible without those risking their lives in the air. Transferring troops and equipment from Britain to Afghanistan, ferrying men and supplies around theatre, evacuating casualties, supporting soldiers on the ground, and managing labyrinthine logistic chains, the men and women of the Royal Air Force are in the thick of it.

At the centre of the airforce's operations is RAF Brize Norton. The West Oxfordshire airbase is the centre of the Air Bridge' between the UK and theatre - a massive logistic feat involving the transportation of soldiers, vehicles, weapons, equipment, supplies and, crucially, mail to Afghanistan, and back.

Operations 'in theatre' are focused on the southern city of Kandahar - where a purpose built joint US/UK airfield has been constructed, providing a stepping stone to the British headquarters at Camp Bastion and beyond.

Kandahar Air Field is a sprawling military city housing 10,000 people, not only from the US and the UK, but Bulgaria, Romania, Denmark, the Netherlands, Canada, Australia and many other lands.

It is a dusty, functional-looking place, next to the city's modernist 1960s-built international airport terminal, and in the shadow of the mountains. But this surreal-looking place is home from home for Oxfordshire's airmen.

Although the base is relatively peaceful at the moment, those based there are only too aware that they could be targeted at any time. During the past year, the heavily fortified site suffered rocket attacks at least once a week.

Brize's fleet of ageing TriStar troop carriers land and take off at night, under cover of darkness - and without lights.

Passengers don helmets and body armour to guard against small arms fire, and the cabin and cockpit lights are turned off for the final approach. The atmosphere on board is tense - and, even with 170 soldiers on board, it is silent.

The Air Bridge is a continuous shuttle from Brize to Kandahar and back, via Muscat, where planes are refuelled and crews change over. It is operated by the airmen of 216 Squadron, who can be on duty for 18 hours at a time.

"If it wasn't for us, none of this would happen and our troops wouldn't get deployed," said one west Oxfordshire-based captain, a Flight Lieutenant who asked not to be named.

"These runs are our bread and butter. This is my 20th flight to Kandahar.

"Afghanistan is inherently dangerous, as it's an operational theatre. But we negate those things by flying in at night with the lights off, and by the way we carry out our approach - making us as invisible as possible.

"People on the ground in Kandahar are also looking out for us. There are lots of things in place to make it as safe as possible."

Even more risky is the transfer of men and supplies around the country. Relying on Hercules transport planes, and Chinook helicopters, RAF personnel provide a lifeline to remote Forward Operating Bases and combat zones.

Again, safety is paramount. Chinook gunners stand guard at the stern, scanning the ground for insurgents, and aircraft are accompanied by fearsome looking Apache helicopters packed with hi-tech weaponry.

Keeping vigil at Kandahar are the men of the RAF Regiment. Out patrolling villages or entrenched in cold, muddy, mortar positions on the fringes of the airbase, it is their job to make sure the base and its aircraft are safe.

"We are here to protect the airbase and RAF assets," explains Flight Lieutenant Jim Baldwin, while his colleagues light up the night sky with illumination flares.

"But we are also here to win hearts and minds, and provide aid to villages."

They are supported by the RAF's latest weapons - unmanned Reaper spy drones, which police the skies. Helping to maintain communications are the RAF's Tactical Support Wing - part of 90 Signals Unit - who spend ten weeks in Kandahar, then 19 back in the UK on training, before returning to theatre for another ten weeks.

Being an American base, the airfield has many of the comforts demanded by US troops - a Burger King, Pizza Hut, Subway, and, for the Canadian contingent, a Tim Horton's Donut Store.

It also has a 'PX' Post Exchange - a supermarket packed full of Hershey bars, peanut butter and Coca Cola, as well as a range of souvenir Kandahar hoodies and baseball caps. There are even stores selling Afghan carpets and jewellery.

"You can sometimes forget you are in a war zone," said Corporal Lisa Byrne, 36, from Brize Norton.

"But we are lucky in that because of what we do, we see what's going on. The main threat is mortar attack - but you're probably just as likely to get hit by a bus back home."

"I previously served in Iraq, but Afghanistan is very different. The threat there felt more immediate and we saw more body bags.

"We have no reason to go outside the wire' here, and are advised against it because of things that go on - such as suicide bombers and explosive devices.

"I was a bit dubious about coming out at first, but the facilities are excellent. We have four-man rooms, sports facilities, a gym, Internet, TV, and telephone - and being the Tactical Support Wing, we provide our own communications.

"I am continually reassuring my mother that we are safer here than further forward.

"And she has given up alcohol in solidarity, for the ten weeks I'm away. I do miss home, but everywhere you go is a new experience."

"We are extremely busy, but then so is everyone," adds Flight Lieutenant Phil Butler, 28, from RAF Brize Norton, who provides computers and telephones for HQ and Air Operations.

"Everything here is changing. New buildings are going up here all the time and new aircraft are coming into theatre, which need different communications and systems.

"It's not particularly sexy, but we are making sure things work. Without us it would be impossible to do all the planning and tracking of supplies and forces on the ground in Helmand.

"Take bottled water, for example. It's critical, and if it hasn't been planned right, or is in the wrong place, people could die.

"I came here expecting it to be bad, but it's not at all. Maybe I'm easily pleased.

"I do miss the privacy of home. But things like having a gym are really important for people to let off steam.

"It's dry' but I don't really miss alcohol. It's a good opportunity to stay fit.

"Also, we need people to be ready to respond and be on the ball all the time.

"I am of the era that it was quite clear when I joined up that I could be coming away and doing this sort of thing.

"There is an end to what we are trying to do and it's rewarding. And that offsets the disruption to family life.

"This is a tri-service operation and we are all playing our part.

"We do not get the same publicity as the guys on the ground, but nothing could happen without us - so we enjoy quiet satisfaction in a job well done."