For a second or two, they look like birds: four tiny black dots in the distance. They swoop down in formation, out of the sun and the deep blue sky, unheard and almost unseen.
Then I remember how high we are, three miles up, and realise how fast they must be travelling towards us – at least 500mph.
Those aren’t eagles or hawks. They’re fighter jets.
I’m onboard an RAF Voyager air-to-air refuelling tanker. Through a window at the back, I watch as those dark spots reveal themselves to be F-35 Lightnings, the most advanced military aircraft in the world.
Their British pilots have been flying in simulated dogfights, practising how to defend the UK and Europe from Russian attack during one of Nato’s biggest training exercises, codenamed Cobra Warrior.
Now their silver machines are thirsty for more kerosene and it’s the Voyager crew’s duty to replenish them. When they’re done, the Lightnings soar away and resume their mock missions – before four Eurofighter Typhoons arrive for a top-up.
The Ministry of Defence granted The i Paper the rare opportunity to observe this top-level Nato training. The exercise will conclude on Friday after three weeks of intensive action.
It’s an otherworldly sensation to see this unfold with my own eyes. The operation resembles a scene from – but taking place in real life, just a few metres away from the pane of glass in front of me.
For the pilots, however, it’s vitally important that they’re ready. Sometimes these fighters are scrambled to intercept Russian bombers or surveillance planes approaching UK airspace. And when they’re sent up, a Voyager crew must join them.
This summer, a Voyager had to join two Typhoons assigned to monitor a Russian warship in the English Channel when it began firing live rounds from its main cannon.
This turned out to be a Russian test, but the air crews wouldn’t have known that at the time, particularly amid concerns about Vladimir Putin’s intentions.
At the outset of the current exercise, the head of the UK air force, Air Chief Marshal Sir Harv Smyth, said: “Cobra Warrior gives us the opportunity to practise our response to aggression, ensuring we are testing our defences and ability to operate alongside Nato partners during a real conflict.”
Harry, a member of the crew – who are withholding their surnames for security reasons – explains how the fighters are “simulating war”.
“We get a blue and a red side, and we chop up areas of the UK. Each day, they’ll be working at pushing that line a little bit further, to try and claim more territory.”
Today, we’re on the blue team – the goodies.
As well as practising how to shoot down enemy jets – by attempting to lock on to them with their radars or heat-seeking sensors, which would allow them to launch their missiles – each side also tries to defend or attack targets on the ground.
Cobra Warrior serves an additional purpose, too: deterrence. “It shows the world that we are a force to be reckoned with,” says Harry, a flight-lieutenant with a moustache and boundless enthusiasm.
The crew don’t mention Russia in our conversations. But they know Moscow will be aware of Cobra Warrior and wary of the lethal jets taking part.
The RAF tanker fuelling Nato jets
Although it depends on how fast they’re flying and if they’re fitted with an external fuel tank – which boosts range but reduces speed and weapons capacity – fighter jets can only fly for two or three hours at most without being topped up.
These jets are “excellent for defending airspace and a great deterrent, but one of the biggest limitations is their endurance”, says Harry.
This is especially true for Typhoons on Quick Reaction Alert (QRA), when pilots wait in their flying suits at all hours, ready to run to their jets during emergencies and take off within minutes to face any potential threats.
They burn fuel faster while “using a high thrust to get to a destination as quick as they can”, Harry explains. An extra fuel tank can reduce speed and weapons capacity.
What’s less well-known is that a Voyager crew is always on QRA too, ready to assist the fighters if they are scrambled.
“We’ll follow them out. We have tactical controllers who will put us in a strategic place and we’ll adopt that area as a fuel station,” says Harry. “We’re there to get them out, get them home, and keep them going.”
A Voyager can carry about 110 tonnes of fuel inside its wings and fuselage, with Typhoons or Lightnings taking on about three tonnes each.
Usually Voyagers operate from RAF Brize Norton, but while the Oxfordshire base’s runway is being upgraded, they’re flying from Glasgow Prestwick airport.
Voyagers are based on Airbus A330-200 airliners and look much the same on board, meaning they can carry up to 291 passengers in addition to fuel. “On air transport trips, we’ll take troops or VIPs across the world,” says Harry.
After taking off at 08.55 Zulu time – that’s 9.55am to you and me – we’re destined for a rectangle of the North Sea codenamed Ultron, about 100 miles off the Yorkshire coast.
On the maps we’re handed, there’s a big red box between three grey refuelling zones. That’s where the fighters will be playing their war games.
Filling up the tank – 16,000ft in the air
About an hour into our flight, we enter the refuelling zone and the crew issue an order: we can no longer use wash basins in the toilets.
Although anything flushed down the loo is stored in an on-board tank until we’ve landed, sink water is dispensed from the Voyager immediately – and fighter pilots don’t appreciate their canopies being sprayed while flying at 300mph.
Two long hoses are now extended from pods under the Voyager’s wings, with drogues – which look like shuttlecocks – at the far end.
When the Lightnings arrive, a pair manoeuvre behind the two hoses, then gradually move forward, each placing a probe – positioned next to their cockpit – into a drogue to receive fuel.
“It’s a real art for the pilots,” says Harry, comparing it to a hummingbird hovering to sip nectar from a flower.
Today, in good conditions, the pilots connect relatively easily, but it doesn’t look so delicate if there’s wind turbulence.
“If it’s too dangerous, the guys will back off,” Harry explains. Pilots don’t want to stab their probe in too forcefully and suffer “hose whip”, when ripples in the pipe can affect stability. Nor do they want to “spoke the basket”, where their probe gets stuck in the drogue’s holes.
Entering the cockpit, I sit at the back next to Owen, a flight-sergeant serving as the mission systems operator. Using several screens and hundreds of buttons, he guides the fighters and controls the refuelling system.
Exercises like this are particularly demanding, with many jets queuing behind the Voyager. “We need to get them through as quickly as we can,” says Owen. Today, he refuels 18 jets in a couple of hours.
Owen is experienced at serving on QRA, when they can be ordered to “get to work and get airborne” with no warning.
He is also prepared to deploy to bases thousands of miles away. This possibility has “ramped up” during precarious geopolitical times, he says.
The Voyager I’m travelling on is also refuelling Typhoons flown by the German air force. A member of the German contingent, speaking anonymously, says it’s healthy for multinational pilots to practise communicating in English – identifying and eliminating potential misunderstandings.
For example, he says, if they are turning to the left, “perhaps for a German pilot that means 30 degrees and for a British pilot maybe 40 degrees”.
Mike Schill, a wing-commander with the Luftwaffe, says the allies must work hard to hone tactics “in times characterised by crises and war”.
Crews from the US, Italy and the Netherlands are also taking part in this edition of Cobra Warrior, which is held twice a year. F-15E Strike Eagle fighters, Chinook helicopters, P-8A Poseidon maritime patrol planes and C-17 Globemaster transporters are among the aircraft involved.
When we come in to land, we’ve been in the air for less than four hours, but it feels much longer after refuelling so many jets so quickly.
Tanker crews might not have the most glamorous job in the RAF, but in exercises like this, their critical importance in helping Nato’s fighters deter Putin is only too obvious.