A monster storm bearing down on the United Kingdom has swept a flight from New York to London in record-breaking time.

It took the British Airways plane less than five hours to make the 5541-kilometre stretch on February 9, clocking a top speed of 1327 kilometres per hour to arrive more than 80 minutes ahead of schedule.

That's the fastest time for a passenger plane crossing the pond since the same airline retired its famed supersonic Concorde in 2003.

As Ciara – now dubbed "the storm of the century" – charges into Britain, airlines are taking advantage of unusually strong wind currents over the Atlantic to make history. But they are also riding a weird quirk of physics – a fast-moving global conveyor belt long known to migrating birds and airlines alike.

So how do winds affect flight time? What is the jet stream? And could supersonic planes – like the old Concorde that once made the trip in less than three hours – ever stage a comeback?

What are jet streams?

Think of a river. As winds sweep through the upper atmosphere, jet streams are the fast-moving currents carving through their heart. They drive the world's weather, acting as conductors on high in the global circulation system. They flow from west to east, in line with the Earth's rotation, which is why it's faster to travel in that direction too. In the case of the record-breaking New York to London flight, planes travelling the opposite way took almost three hours longer. In Australia flights west to Perth from Sydney or Melbourne will be at least half-an-hour slower than the other way around.

Much of what we now know about jet streams is credited to bomber pilots flying during WWII, but the phenomenon was first noticed by a Japanese meteorologist in the 1920s and is also found in the gases of Jupiter and Saturn.

The currents form when hot and cold air collide and can reach speeds of more than 440 kilometres per hour. According to Craig Burke, a senior aviation meteorologist at the Bureau of Meteorology, the wind has to be faster than 100km/h, or it's not a jet stream.

Usually, each hemisphere has two main jet streams – a subtropical stream and a stronger polar jet that runs at a lower altitude, though others can form. Down south, the polar jet mostly encircles Antarctica, sometimes sweeping across to the tip of South America, and slingshotting ships along the bottom of the world.

But the most widely known polar jet cuts through the Northern Hemisphere, low enough to batter climbers on Mount Everest. It reaches its fastest speeds about 10 kilometres off the ground, where planes fly, and its underbelly can reach the ground in howling westerly winds. It is at full strength in winter, when it draws on the cold air usually locked in circulation around the Arctic by the Polar Vortex. Sometimes it brings wild weather in its wake, famously pulling Hurricane Sandy to shore in the US in 2012 and now storm Ciara in the UK.

Not long before Ciara was making landfall, a huge downpour was hitting NSW and much of south-eastern Australia. Burke said that fire-quenching rain was actually triggered by a collision in the upper reaches of the atmosphere overhead – between a humid subtropical stream and a polar jet.

How do planes use jet streams and what are tail winds?

Jet streams have been harnessed for air travel since the 1950s. Meteorologists such as Burke are now embedded in air traffic control centres all across the world to war game the day's best flight paths based on where the winds are blowing. Predictions are getting better all the time, he says, drawn from satellite data, weather balloons and even sensors in the planes themselves. Where once the skies were a highway, with just a few routes mapped out, now experts continuously tinker to catch the fastest winds – or avoid those blowing the wrong direction, even mid-flight.

In the case of that record British Airways flight, US meteorologist Ryan Hanrahan said pilots jumped on the strongest part of the northern polar jet, known as the jet streak, which created tail winds of more than 320 km/h and helped spawn storm Ciara. All up it took the plane just four hours and 56 minutes to get from JFK to Heathrow – beating a previous subsonic record for the crossing of five hours and 13 minutes set by a Norwegian flight about a year earlier. A Virgin Atlantic Airbus that landed at Heathrow moments behind the British Airways flight was only a minute slower, another plane the following morning just three minutes behind.

"The polar jet must have lined up so perfectly with London," Burke says. "It was remarkable."

Polar jets are strongest in winter, he says, including in Australia, where they can reach 200 to 300 km/h. But weaker subtropical streams are most common overhead, particularly in summer.

A lot of other winds affect flight – notably headwinds, which are strong winds into which a plane is taking off for lift, and tailwinds, which push along the plane from behind.

"Of course, jet streams can give really favourable tail winds," Burke says.

Do jet streams cause turbulence?

Aviation safety expert Geoffrey Dell says the wind currents can shave up to two hours off a long-haul flight flying east into Australia. But while they can save fuel and time, they can also cause headaches for pilots and passengers alike.

"If you're facing down a stream blowing the wrong way, you might have to drop altitude or shift course," Dell says. "Even if you're going the right way, it can be a bumpy ride. The air tends to get a bit rough around the edges of a jet stream."

A phenomenon known as clear air turbulence, which is virtually impossible to detect with either on board instruments or the naked eye, is often associated with the wild currents.

Indeed, the hurricane-force winds of the jet stream howling over North America grounded scores of flights even as it helped others smash records. A British Airways spokesman stressed the airline always put safety ahead of speed records. "But our highly trained pilots made the most of the conditions to get customers back to London well ahead of time," he said.

What's the difference between subsonic and supersonic flight?

While that flight made headlines when it broke the record for the fastest subsonic crossing, it didn't break the sound barrier. Down on the ground, its top speed of 1327 km/h would have felt faster than the speed of sound, which stands at 1236 km/h, but the plane was already tangled up in a strong push of air from the jet stream, meaning the dial in the cockpit likely hovered closer to 1054 km/h.

Dell says supersonic flight – travelling past the barrier – requires much more power. Think fighter jets and rockets, or a bullet fired from a gun. There's a distinctive boom, like a crack of thunder. But it's not impossible.

More than 40 years ago, commercial planes were crossing the world at twice the speed of sound – on board the famed supersonic Concorde (or its Soviet equivalent dubbed the Tu-144).

"The Concorde was ahead of its time," Dell says.

With its characteristicly droopy nose, it was also remarkably small compared to other commercial airliners. The fuselage could seat only about 100 passengers, with two seats on either side of the aisle. The ceiling was low, and the cockpit cramped in order to minimise drag.

The aircraft had only one accident in its time in the skies – an Air France plane that crashed just after takeoff in 2000, killing all 109 people on board and four others on the ground. But even by the late '70s, backlash against its noise – that infamous sonic boom – led to headaches for airlines. Dell says many countries, including Australia, banned the Concorde from flying over their airspace altogether, leaving fleets such as those run by British Airways and Air France consigned to international waters.

"That made the track time too long and started to eat into its benefits, it cost so much to run," he says. "But it was a great design. For places like Australia, it could have changed how we travel, cutting down travel times in half, but all the political hoo-ha was too much."

Are planes getting faster?

When commercial planes first started taking off from Australia, Dell says they flew much lower than they do today. As their technology has developed, they have climbed further into the atmosphere, where the air is thinner and in turn, less fuel is needed to hit speed.

"The planes are getting lighter, their wings are more aerodynamic, they get more lift," Dell says.

But while fuel efficiency has made big strides, driven in part by the end of aviation's Golden Age, top speeds have remained relatively unchanged. On average, a commercial plane still cruises at about 925 km/h.

"They hit a wall then, and to push past the sound barrier you've got to think about design changes, power," Dell says. "It gets costly."

But, almost 20 years after the last Concordes were grounded in 2003, the race to make supersonic flight viable has been taken up once again. A number of tech companies are developing new models, including Boom Supersonic, which envisions more cost-effective fares than those astronomical tickets once snapped up by the world's elite for a ride on a Concorde. NASA is also testing devices to break up the window-rattling shock wave of sound caused by supersonic flight.

Is hypersonic flight the future of plane travel?

Other companies are experimenting with automation or electric propulsion instead of the standard air-breathing combustion engines. Such planes could potentially fly lower to the ground – even as door-to-door taxis – or higher still, to the edges of space.

Boeing has plans for a sleek intercontinental "hypersonic" craft, which would use a new kind of engine requiring less air or processing much hotter air and so able to fly at higher altitudes.

"Its sort of like a rocket and plane engine hybrid," Dell says.

Hypersonic flight would make planes five times faster than the speed of sound, according to NASA. That could put a four-hour flight from Britain to Australia in the air by the 2030s – if a new hypersonic engine in development by the UK Space Agency gets wings. The German Aerospace Research Institute wants to cut that time down even further, to just 90 minutes, carrying about 50 passengers at 25 times the speed of sound.

And that's even before things get sub-orbital – as tech moguls such as Richard Branson and Elon Musk gear up for the coming space tourism boom.

If all else fails, there’s the case of skydiver Marc Hauser, who in 2018 flung himself into the winds above Australia to draw attention to the jet stream’s potential as an untapped source of clean energy. He survived, becoming the first person to travel 270 km/h in a jet stream – outside a plane.

With agencies