Speed question
Feb 5, 2007, 6:47 am
#1
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Speed question
Last night while taveling home from FLL on JetBlue 510, and enjoying the Superbowl, I glanced over to the Livemap in the seat next to me and saw it said 670 mph. Is that possible in a 320? The pilot said we had a good tailwind(and a lot of turbulence), but I thought that was a little fast for a jetliner.
Thanks
Rich
Thanks
Rich
Feb 5, 2007, 10:38 am
#3
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I've seen the AA Airshow display a ground speed of 720 - 725 mph or so on eastbound LAX-LHR flights and eastbound NRT-USA flights.
With enough tailwind, couldn't a jetliner go 1000? Too much airspeed and the airplane falls apart. But strong tailwind plus safe airspeed can equal very fast ground speed.
With enough tailwind, couldn't a jetliner go 1000? Too much airspeed and the airplane falls apart. But strong tailwind plus safe airspeed can equal very fast ground speed.
Feb 5, 2007, 6:48 pm
#5
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Indeed, as this site records.
Kinda cool considering the speed of sound at sea level is 661kts / 761mph.
But you do get some pretty fast winds up there.
Kinda cool considering the speed of sound at sea level is 661kts / 761mph.
But you do get some pretty fast winds up there.
Feb 5, 2007, 9:42 pm
#7
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Groundspeed could go to any theoretical maximum without affecting the airframe.
In fact, when the space shuttle is contra-rotating the ground speed is something like mach 25 or so.
Bada-boom! Physics baby!
In fact, when the space shuttle is contra-rotating the ground speed is something like mach 25 or so.
Bada-boom! Physics baby!
Feb 6, 2007, 7:25 am
#8
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I've seen in excess of 800mph, the pilot telling us we had a tailwind slightly exceeding 200mph. Most aircraft stats I've seen have a cruising speed of 575'ish, which is relative to the airflow, so upper 700's-800 isn't our of the question.
Going the other way, you're chugging away at about 375. That makes for a long flight. In reality, I suspect the flight would be routed around the jetstream, where possible.
From the site above, it looks like 734 knots, or 845mph, is the fastest captured for a commercial jet - an A340. That looks like it had a 275mph tailwind. Wow. (Of course, there's the Concorde at 1386mph...)
Going the other way, you're chugging away at about 375. That makes for a long flight. In reality, I suspect the flight would be routed around the jetstream, where possible.
From the site above, it looks like 734 knots, or 845mph, is the fastest captured for a commercial jet - an A340. That looks like it had a 275mph tailwind. Wow. (Of course, there's the Concorde at 1386mph...)
Last edited by CPRich; Feb 6, 2007 at 7:31 am
Feb 6, 2007, 11:50 am
#9
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And to the uninitiated to hear that their 700 MPH flight is showing an airspeed of something like 200-300 kts is mind-boggling.
Feb 6, 2007, 4:18 pm
#10
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I've seen 693 MPH (600 kts) on a Boeing 777 with a 130 MPH tail wind.
Quite a bit of turbulence though.
The cruise speed for the aircraft type varies but it's typically around 0.83-0.85 Mach for the larger ones. The speed of sound is about 660 MPH (at cruise height) so the cruise speed is about 660 x 0.85 = 560 MPH. You'd need around 140 MPH tail wind to crack 700 MPH.
Quite a bit of turbulence though.
The cruise speed for the aircraft type varies but it's typically around 0.83-0.85 Mach for the larger ones. The speed of sound is about 660 MPH (at cruise height) so the cruise speed is about 660 x 0.85 = 560 MPH. You'd need around 140 MPH tail wind to crack 700 MPH.
Last edited by Ex Amex Card; Feb 6, 2007 at 4:25 pm Reason: Added calculations