Wavy jet stream
[image credit: BBC]
Fly like the wind – but not your everyday wind.
Airplanes often receive a speed increase from air currents high in the skies, but very few get an insane boost like this: helped by a tailwind of more than 322 km (200 miles) per hour, a Boeing 787-9 jet reached a ground speed of 1,289 km (801 miles) per hour on Monday night, reports Science Alert.
The top speed was recorded by the Virgin Atlantic commercial flight from LA to London while over central Pennsylvania, at somewhere around 10,670 metres (35,000 feet) above ground.
"Never ever seen this kind of tailwind in my life as a commercial pilot!!" tweeted Peter James.
That's above the speed of sound (1,234 km or 767 miles per hour at sea level in normal conditions), but there was no sonic boom.
Because the airplane was being ferried along in a stream of fast moving air, the airplane was only travelling at somewhere near its usual cruising speed in relation to the air around it.
Boeing-787-9
Thanks to the jet stream buffer, the flight landed at London Heathrow 48 minutes early.
Jet streams are caused by circulating air high up in the atmosphere, due to differences in temperature between different air masses. The main jet streams move from west to east, benefitting planes going in that direction but counting against them when they're coming the other way.
Flight times can often be affected, but you'll usually find they're well accounted for in airline timetables… until, that is, a particularly strong jet stream comes along.
Full report here.
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