A Virgin Atlantic flight yesterday on the grueling journey from Los Angeles to London reached a speed of at least 801 mph, thanks to a rapid trail of air in the jet stream over Pennsylvania. . You are probably wondering how it is illegal to cross the sound barrier above the earth, but despite exceeding the speed required to do so, there was no sonic boom.
And no, the Virgin Atlantic flight was not in a very special mysterious plane that you have not heard of. And no, they do not bring back the Concorde. Here is what happened.
The ground speed of 801 mph Boeing 787-9 was reported on the Flight Aware Flight Tracking System and was tweeted by meteorological professor Stu Ostro:
The typical cruising speed of an aircraft of this size is only about 560 mph, which is far removed from the speed of sound (767 mph) (although the speed of sound varies depending on altitude, air temperature, pressure, etc., and this figure of 767 mph is based on a reading at sea level under normal conditions). And that's precisely why there was no sonic boom for this 801 mph flight. I will let the Washington Post explain:
With a maximum speed currently over central Pennsylvania, planes crossing the jet will be either accelerated or slowed down, depending on the direction in which they are heading. It's like the mobile gateway of the airport. You have your own speed of advancement, but if you continue this speed in a moving environment, it can propel you at an impressive speed.[…]
Commercial aircraft generally can not cross the sound barrier because they are not designed to cope with the sudden increase in drag and other aerodynamic effects associated with these speeds. Despite such a high ground speed, the aircraft did not fail to reach this threshold because it was embedded in the rapidly moving air.
The airplane, in this case, was essentially driven at this speed by the air around it. Thus, even if his ground speed was higher than the speed of sound, his speed was not. Otherwise, the stress of flying at or near the speed of sound would add a significant burden to the body of the aircraft and its control surfaces, and could result in disaster. If an airplane is not supposed to go faster than the speed of sound, it really should not.
Although it did not stay very long in the northeastern jet stream, the plane managed to arrive 48 minutes earlier in London and most flights to the east. from this region of North America should have shorter flight times in the coming days. Of course, any reverse flight will either have to fight against the wind, or turn around, so that the flights will last longer.
The Post reports that jet stream winds are generally faster in winter, due to the maximum temperature differences between North and South North America.
It would be quite shocking to watch the flight monitor in the infotainment display of my headrest on a flight like this and see everything north of 700 km / h, still less than 800 km / h. The best advantage of the wind is that it allows you to overtake Pennsylvania as quickly as possible.