When the weather's bad in the Highlands, it's really bad. Here we tell the story of the hard-working engineers who recently helped restore signal to some of Scotland's most remote areas...
When you’ve got high-tech equipment exposed to the elements in one of the coldest parts of the country, extreme weather can occasionally cause network outages. That was the case for us recently in the Scottish Highlands, with the full force of the January snow, strong winds and rain thrown at both the electricity grid and our network.
So how do you fix a broken mast or a misplaced microwave dish? You put on your biggest coat, leave your fear of heights at home and open a tin of elbow grease. We’ve been speaking to Vodafone’s network repair team in the north for the inside story on battling Mother Nature, trekking through snow and avoiding icicles…
The science behind a signal outage
When the British weather wants to act up, it can be a real nuisance. This January, some of the least accessible parts of our mobile network in the Scottish Highlands and Islands suffered in the face of deep snow and extremely high wind speeds, so to get things working again we needed our best team on the ground. But it wasn’t all plain sailing. Here’s Vodafone UK’s Head of Networks in the north, Dan Raine, to explain how and why the network can fail, and what we have to do to set things right. First up, a quick science lesson:
“Quite a lot of our transmission in the north is deployed using microwave technology,” he says. “Essentially, that means that we have dishes on a number of masts that transmit the signal from one to the other until it eventually goes into a fixed line, and back to our network controller and switching sites.”
Dan explains that these microwave dishes are used extensively throughout the Highlands and Islands because they’re great at sending the requisite information over the huge distances between settlements you find in the more isolated parts of the UK:
“In London, for example, there’s a lot more fibre connecting sites: due to the remote locations in Scotland, we need to microwave the signal over long distances via a series of masts.”
It’s a neat solution, but because these masts are exposed to some of the harshest weather around, things can occasionally go off kilter:
“We’ve had some severe weather these last few weeks: we’ve been OK with the heavy snow,” says Dan, “but very strong winds are challenging. When we had outages recently in Knapdale and Argyll, we recorded wind speeds of more than 100mph. Winds at that speed can misalign even the most secure microwave dishes, and if you lose the line of site from one to the other then you’ve lost that link. And that’s when we need an engineer to go out and physically realign them.”
Enter Iain Macleod, Vodafone engineer extraordinaire…
Getting up and down
“We were called out to get the masts fixed – James Connelly and I were just two of many engineers who were involved,” says Iain, who tells us that he’s had a busy few weeks in several snow-capped areas of the Scottish highlands.
“We ended up staying at the first site on the Isle of Mull, at a site called Torrosay, for three days without a change of clothes, only what we had on. During the first two days we walked up the hill with the harnesses, tools and spare kit in the snow, only to realise that we couldn’t climb the mast because of the severity of the conditions. From then the situation just tumbled,” he says, “and we had several further outages because of the weather. At one point we just had to watch as lightning struck another provider’s cabin.”
And as Iain explains, the trickiest thing about fixing these remote sites isn’t doing the repairs – it’s actually getting to them:
“There were sites where we had to abandon the car and walk for miles,” he reveals. “At some sites we had to leave the car at the foot of a hill and walk two miles up the hill in deep snow, with all our equipment in hand.”
And then, when you do finally get there, fixing a mast is no walk in the park:
“There are all sorts of challenges,” Iain says. “As you can probably imagine its pretty cold up there; you need to look out for falling icicles, windy conditions, slippery surfaces and things like that. You’re very exposed as well, so you really have to watch what you’re doing with your footing. It’s a case of taking your time, thinking about what you’ve got to do, and being careful. As a team we look out for each other and make sure we stick to our safety guidelines to stay safe.
“Sometimes you can get up and down in half an hour, but it depends what’s wrong with each site. Sometimes you can be up there for well over two hours, including climbing up and down to get other tools. They all vary.”
A complex problem needs a complex solution
Because these remote sites are so connected, when one fails it can cause a daisy-chain effect, affecting other sites. As a result, Iain is just one of dozens of hard-working Vodafone engineers who’ve been battling the elements relentlessly over the past few weeks – on foot, in helicopters and in snowbound all-terrain vehicles. And, as Dan Raine explains, these operations aren’t helped when the national grid goes down…
“The big problem with the outages we just experienced in the Highlands was the loss of power,” he tells us. “There was a power outage across large areas of Scotland initially. Whilst our key sites have battery backup of between 4-6 hours, the grid was off-line for much longer periods, as the power companies were experiencing the same difficult working conditions as us.”
“If the power is out to a significant number of sites because of the weather then we target the key hub sites with generators to restore them as soon as possible (weather and safety permitting). Then we have to triage any remaining network issues once the power is restored by the energy companies. We can normally respond immediately,” he says. “We can go and fix sites that day, but in this case the sheer scale of the problem – the power and the snow – made things trickier.”
The good news? These kinds of outages are very rare, and are only caused by extraordinary weather conditions. And on top of that, Dan, the networks, and our service operations teams are looking at long term solutions to make sure that it won’t happen again anytime soon:
“We’re looking at making our transmission sites more resilient in the short term,” he says in closing. “All of the radio sites are already planned to be upgraded as part of our current network investment activity, too.” And you can read all about that big next step for the network right here.
A day in the life of a network engineer… What’s it like work 100 metres up in the air? Click here to find out how climbing some of the UK’s tallest structures is all in a day’s work for a Vodafone network rigger.