TO the traveller, passing through in a haze of holiday happiness and suncream, Glasgow Airport is just an airport – a busy, bustling hub of people coming and going, checking passports, buying duty free, boarding planes. Behind the scenes, however, lies another world, populated by secret wardrobes and eagle-eyed birdmen; a world of (unsuccessful) snake-smuggling and crack teams of litter-pickers; of lost-teddy finders, giant snowploughs and electronic scarecrows.

It even has its own mysterious language – terms like FOD team, Long Grass Policy and Norwegian RS400s are only the tip of the iceberg, hinting at the fascinating "other" life of Glasgow Airport, which celebrates its 50th anniversary this month.

“The airport is like a mini-city,” says airside operations manager Louise Hurst. “Our job is to keep everyone in it safe, and to make sure they speak highly of the place when they leave.”

Hurst’s remit includes everything from litter-picking and bird control to overseeing winter operations and "parking" the aircraft – guiding them from the tower – once they have landed.

Hurst, a self-confessed plane geek, got her first job at Glasgow Airport almost by chance. “I was working as a car saleswoman in Paisley when I went on a test drive with someone who worked for British Midland,” says the 38-year-old, who lives in Hamilton.

“During the journey, she told me all about her job and it sounded fascinating. I went for an interview and from the moment I sat down, I was gripped. It’s not a nine-to-five job, but that’s why I like it.”

One of her biggest challenges is coping with winter weather. “People say Brits talk about the weather all the time, but I actually do talk about the weather all the time,” she says. “It’s critical, of course, that we are aware of changing conditions. We subscribe to a specialist weather monitoring system which provides highly accurate and in-depth forecasts. We get three a day and every 24 hours we receive a two to five-day forecast.

“We operate on a red, amber, green alert system. If the alert indicates an amber snow warning, we immediately call out our winter operations team – it can involve a fair bit of waiting around but it’s essential we can get all hands on deck as quickly as possible.”

As the airport fills up with holidaymakers over the next couple of months, Hurst and her team are already preparing for winter snow.

“Our programme gets into full swing in the middle of summer, starting with intensive training and retraining exercises, on things like how to clear stands, roads and taxiways, how to use snow-clearing tractors and ploughs,” she says.

“In winter, the size of our airside operations team more than doubles. We recently took delivery of two brand-new RS400s from Norway – these are heavy goods vehicles which operate at a great pace, clearing snow from taxiways and runways.

“In Scotland, our snow tends to turn icy very quickly – it’s different from the dry powdery snow that lands in North America and makes it more challenging.”

Out on the runway, airside operations officer Kevin Ferguson is carrying out airfield ground lighting check. Given clearance to proceed by the NATS (National Air Traffic Service) tower, the lights are switched on and Ferguson drives swiftly up the length of the runway, checking for blown bulbs and debris on the ground. “We do the light check once a day, and a routine FOD check of the runway, taxiing areas and aprons, once an hour,” he explains. FOD stands for foreign object debris, meaning anything from a crisp packet to a luggage strap.

Today there is nothing on the runway, but Ferguson spots something glinting in the sun near one of the aircraft stands. “It’s a zip, probably off a bag,” he says, hopping back into the vehicle after retrieving the offending object.

“That’s the most common kind of thing we find – bits of bags, wheels off the bottom of suitcases and litter that has been blown about. They seem small, but those are the kinds of things that could burst an aircraft’s tyre.”

Sometimes, the power on take-off of big aircraft like 747s can dislodge edge lights on the runway and even a crisp packet on the runway can be a matter of concern. “We are also looking for potholes and other debris," adds Ferguson, "and we have to keep the tower updated about the surface conditions – whether the runway is damp, wet or dry.”

Ferguson has worked for Glasgow Airport for four years, but his interest was sparked as a young child. “I grew up in Drumchapel – we lived underneath the flight path – so as a wee boy I was fascinated by these big planes zooming overhead,” he says, pulling over to let a departing plane pass as it makes its way towards the runway.

When he is not carrying out routine checks, he can be guiding private aircraft – “Sticking the Follow Me signs on the back of the car is fun,” he says – or marshalling with "ping pong bats".

One of the most important airside ops jobs is bird control. A bird control officer is on duty 24 hours a day. The Long Grass Policy, to discourage birds from nesting, means all grassed areas must be between six and eight inches long, and all airside ops officers have shotgun training for the worst-case scenario. The most effective deterrent, however, is the electronic scarecrow, which is fitted to all the vehicles. “It’s a recording of different distress calls made by a variety of birds – if we play these at high frequencies it’s usually enough to scare birds away,” says Hurst.

“We also look after an area extending to around 13 kilometres outside the perimeter fence – so, for example, if someone wants to create a lovely duck pond within that area, it has to come through us. Lovely for the public, but it would mean more birds, and that means more risk to aircraft.”

Up in Glasgow Airport’s operations tower, airside ops officer Lynsey Sutherland is "parking" assorted aircraft. “It’s a bit of a jigsaw puzzle, as not all aircraft fit all stands,” she explains. “We’re co-ordinating maybe 25 to 30 planes an hour at peak times, so you are constantly watching what’s happening and listening to both ground and tower frequencies.”

The 35-year-old from Bishopton got a summer job at the airport 17 years ago and never left. “I loved the atmosphere, being surrounded by happy people going on holiday – it was such a nice feeling,” she says.

“We work 12-hour shifts and they are incredibly varied. We could be outside, handing out parking tickets – you’d be surprised how many illegal parking issues we have. It could just be a piece of equipment parked outside a marked bay, but if it clips an aircraft coming in to the stand, it could cause a lot of damage. Or we could be in here, making sure aircraft get to where they need to be safely.”

Around 5,500 people work at Glasgow Airport, but only some 500 are employed directly – the rest, including check-in staff, airline crew, baggage handling, border force, cleaning, facilities management, hotels, retail, catering and car hire, are separate businesses.

In recent years, managing director Amanda McMillan and her team have worked hard to create a "one campus" mentality, as head of human resources Craig Martin explains.

“We run joint training exercises, campus award schemes, and publish a shared vision,” says Martin, 46, who lives in the west end of Glasgow. He joined the airport five years ago. “It works well. There is a village atmosphere, almost – this place gets under your skin, in a good way. So no matter what your job is, you can’t ever walk by if something is needing done, you have to do your bit.”

Craig Norton, duty manager, agrees. “We work together, to make sure everything goes to plan. But when things do go wrong, we have to make sure our response is smooth,” says the 35-year-old. “Duty managers liaise with airside ops, security, management – everything goes through us, whether it’s planes being re-routed because of problems at other airports or crashes on the motorway impacting on us, or news coming in of terrorist attacks.

“When something happens, like the recent attacks in Brussels, things get more tense. Smartphones have changed our jobs – we hear about things as they happen but so does the public. So emotions do run high, people get scared. It’s our job to help reassure them.”

Serious incidents at Glasgow Airport are rare, but in June 2007 two terrorists drove a Jeep laden with explosives into the entrance hall in a failed suicide bombing. Five people were hurt and one of the two bombers died later from burns. The other is in jail serving a life sentence.

Head of security Kenny Welsh was shopping with his children for holiday clothes when he got the news. “You don’t expect something like that to happen but you do prepare for it,” says Welsh, who oversees 250 security staff, working closely with Police Scotland and UK borders agencies. “My job hasn’t changed that much – the main issues are still the same, with people not up to speed about bag regulations and what they can and cannot take on board an aircraft.

“But in terms of the level of threat having increased? Just take a look at the world.”

There are lighter moments for Welsh and his team. “People joke about going on holiday with everything but the kitchen sink,” he smiles. “But I have seen someone try to take a kitchen sink on to a plane.

“We once stopped a gentleman with a snake curled under his armpit. We’ve stopped people with goldfish, cats in bags, CS gas canisters, knives … We get a lot of stag and hen parties coming through too, and some of the things they have in their bags require a bit of discussion.”

The liquid ban on hand luggage still causes consternation, as Welsh explains. “The most common question we are asked is: is water a liquid?” he sighs. “It’s important to get queue levels right too – we are processing up to 2,000 passengers an hour, but if the queues are too long, people get frustrated and angry. If they are too short, people think you are not taking security seriously enough.”

The 48-year-old, who lives in Alexandria, adds: “If we get it wrong, Glasgow people are not slow in telling us. But I think we do achieve a balance, on the whole – you don’t want to be too scary. You want people to come back.”

In the terminal building, Karen Hardie is on a mission to reunite a lost teddy with its owner. One of nine airport ambassadors, she is there to act as the “eyes and ears” of the duty manager. “Every day is a school day in here,” grins the 55-year-old, who is from Bearsden. “We are like mobile information desks, responding to whatever needs done – if we see big queues, or spot a nervous passenger needing help finding the right desk, we can step in.”

The teddy and its tearful owner are soon back together, much to everyone’s relief – “we put out a call on Twitter and thankfully someone spotted it” – but there is little time to pause for breath.

The ambassadors have their own clothing store, in case nervous children are sick or babies need a change or rips and tears need mended. “There is no typical day – I could be helping someone who has put a glass through her finger and then escorting the singer Jess Glynne through the airport,” says Hardie, who trained as a nurse at Glasgow Royal Infirmary before joining Monarch Airlines as cabin crew and then joining the ground staff.

“You don’t really get starstruck when celebrities come in. Doesn’t matter to me if you’re Gerard Butler or an elderly lady from Paisley who hasn’t flown in 40 years – my job is to make them feel welcome, and help them get where they want to be.”

Keith Banks, airport chaplain, is a common sight in the terminal building. The Salvation Army chaplain, who joined the airport seven years ago, says he is as likely to be asked where the toilets are as he is to be called on to provide emotional support and solace.

“I get to know everyone, walking around the terminal building,” he smiles. “We’re like the beating heart of the airport – most of the time you are not aware we are here, but if you need us, the heart beats a bit faster and we spring into action.”