by Hugh Morris, The Telegraph, February 25, 2019
A Virgin Atlantic jet set a new speed record on Monday, flying from LA to London in just over nine hours, after a powerful jet stream propelled it faster than the speed of sound.
The 787 Dreamliner was clocked at 801mph over Pennsylvania as it rode the fastest jet stream on record, blowing east at 231mph. The velocity only lasted briefly, but was far faster than the usual cruising speed of 561mph for the Boeing aircraft.
The winds high above the ground helped Flight VS8, half-way into its journey from Los Angeles to London, arrive at Heathrow nearly an hour ahead of schedule.
A spokesperson for Boeing told CBS News: “Wow, that’s fast.”
Airline captain Peter James wrote on Twitter: “Never ever seen this kind of tailwind in my life as a commercial pilot.”
Despite the speed registering faster than the speed of sound (760mph), the plane would not have broken the sonic barrier as it was helped along by fast-moving air, so, relative to the air, the plane was travelling slower than 801mph. Passenger jets traditionally travel at about 80 per cent the speed of sound.
The flight completed the journey in nine hours and 14 minutes, much less than the 11 hours scheduled. Other planes flying on Monday night also experienced bumps in their speed, including a 737 aircraft - the type flown by Ryanair - which hit 700mph. BA Flight 112, a 777, hit 777mph, leaving New York for London.
The fastest transatlantic crossing, of course, belongs to a supersonic aircraft, when on February 7 1996 a BA Concorde flew from New York to London in just two hours 52 minutes and 59 seconds, hitting a top speed of 1,350mph - and comfortably breaking the sound barrier.
A Virgin Atlantic Los Angeles-to-London flight on Monday got a ride on an especially powerful jet stream, reaching a stunning 801 mph while over Pennsylvania.
This appears to be a record for the Boeing 787-9 twin jet, which ordinarily cruises at 561 mph. https://t.co/Fqf1FDivp4
— David Priess (@DavidPriess) February 19, 2019
What is the jet stream and does it cause turbulence?
The previous high-speed record for a Dreamliner was set by a Norwegian aircraft, which completed the journey from New York to London in just over five hours, hurtling along at 776mph, surfing high-altitude winds of 202mph, but those on the ground would have been oblivious.
According to a reporter at the Washington Post, the weather on the ground on the east coast of America on Monday, while the atmospheric breeze blistered at 35,000 feet, was calm.
The jet streams are used daily by pilots crossing the Atlantic, helping airlines plot their course depending on where the winds are blowing.
In 2015 a British Airways 777 reached speeds of 745mph as it rode a 200mph-strong jet stream. Alastair Rosenschein, a former British Airways pilot, told the Telegraph: “It’s just like surfing. It’s extraordinary how fast you can go.”
It is not clear whether passengers on-board the record-breaking Virgin flight would have noticed they were soaring through the sky at a mighty speed, but the jet stream can contribute to turbulence.
British Airways captain Steve Allright explains: “Air tends to flow as a horizontal snaking river in a jet stream. A jet stream can sometimes be thousands of miles long but is usually only a few miles wide and deep. Depending on the direction of travel, our flight planners either avoid (into a headwind) or use (into a tailwind) these jet streams to cut fuel costs, as they can flow up to 250 mph.
How fast do planes fly?
“Just like a fast-flowing river swirling against the riverbank, where the edge of the jet stream interacts with slower moving air, there may be some mixing of the air which causes turbulence.”
Patrick Smith, pilot and author of Cockpit Confidential, agrees: “Flights over mountain ranges and through certain frontal boundaries will also get the cabin bells dinging, as will transiting a jet stream boundary. But now and then it's totally unforeseen.”
Does only the Atlantic have a jet stream?
Nope, the swirling winds a few miles up occur around the world.
In 2016, Air India snatched the title of world’s longest non-stop flight route by switching the direction of travel on its Delhi to San Francisco route, taking advantage of a 86mph tailwind to cover 9.506 miles in just 14-and-a-half hours.
Secrets of air travel
“The Earth rotates from west to east, and winds flow in that direction too,” a senior Air India official told the Times of India . “Flying west means facing strong headwinds, that decrease an aircraft’s actual ground speed, and flying east means getting strong tailwinds, which do the opposite."
He said that flying across the Atlantic usually means headwinds of 15mph, making the aircraft’s speed around 482mph, whereas the eastern route over the Pacific usually encounters tailwinds of 85mph, making the aircraft’s ground speed around 582mph.
This article was written by Hugh Morris from The Telegraph and was legally licensed through the NewsCred publisher network. Please direct all licensing questions to [email protected]