Alitalia B763 SUPERSONIC??


WOW!! At one point this baby was travelling at 637 kts (Mach 1.10)!! Is this possible? … /KMIA/LIRF


With wind it is.


While rare, the jet stream is capable of adding 215KTAS or more to an aircraft’s speed.



And they STILL might have been passed by a Citation X 8)


What the others are trying to say is you are looking at ground speed, not airspeed. The speed you see in the scheduled column is the planned true airspeed for cruise, in the actual column you are seeing the ground speed as calculated by the radar facility.


yeah I know that but structurly, would the plane handle that?


Think of a plane as a boat.

River is calm, and you are going 10 knots. Your ground speed is 10 knots

Now add a flow down that river of 5 knots. Boat will still go 10 knots, but now you have force helping you along an additional 5 knots. (tailwind for an airplane)

Keep in mind, boat is going 10 knots on the speedometer, but total “ground” speed is now 15 knots due to the 5 knot push of the water.

Boat doesn’t care structurally, it only knows it’s doing 10 knots in the water.

For purposes of energy (fuel), replace the boat with a human swimmer.

You will cover more distance swimming with the flow of water then in calm waters using less energy (fuel) to get downstream.

Same principle with a plane.

Hope this makes sense.



Again, it’s ground speed, not air speed.

The plane is not traveling through the air any faster than normal, the air just happens to be going in the same direction at a very high speed.


what the difference between groudspeed and airspeed?


cue the dead horse emoticon :wink:


Airspeed is the speed through the air. Ground speed is airspeed plus the effect of the wind. It’s the speed the aircraft is doing over the ground. If the aircraft is doing 120 knots and the wind is directly directly on the tail of the aircraft at 10 knots then ground speed is 130 knots (120 + 10).

Conversely, if the aircraft is flying into the wind, then the ground speed is 110 knots (120 - 10).

The above is just a simplification. I’ll leave it to others to give you a PhD thesis on it.


As above plus:

…just as it is possible to have a 767 have a ground speed of +mach 1, it is possible with a strong head wind to have a ground speed of zero in a light plane such as a C-152 and not stall.

this link gives you an idea of what airliners are dealing with each day. … can-e.html

My apologies for making everyone side scroll, but I like the graphic.


Here’s a nice map for winds in the US. You can click on selected altitudes from surface to FL480. It’s not uncommon to see 125+ kt winds at FL300.


Many pilots used a device called the E6B to calculate, among other things, the ground speed. If you would like to see the effect of wind on ground speed, go to the E6B Emulator and scroll down to the “Heading, Ground Speed, And Wind Correction Angle” section.

*Disclaimer: This is not an endorsement of the page. I cannot verify the accuracy **or **inaccuracy of the page. I am presenting it only for educational purposes. Any disparaging remarks about me giving “incomplete” or “inaccurate” information by any person or persons, especially those who have a domicile in the area bounded by the longitudinal lines extending from 88 degrees west to and including 91 degrees west and lines of latitude extending from 30 degrees north to and including 35 degrees north, will be summarily disregarded. This does not mean that I will be in agreement with that person or persons. In fact, probably just the opposite will occur. *

Edited to add: Remember: This is just an educational posting. It is strictly meant to show a demonstration of the effects of wind speed on an aircraft.

I’m the better man. I will not suffer condescending fools to ruin my day, especially those that cannot read my disclaimer.


Wow…thanks, Dami …that took me back…TC


Me too! Waaaaaaay back! The picture of the E6B that is.

So way back, that I can’t even remember where my E6B is! Maybe if I dig around enough, I will find my first grade abacus next to the aviation form slide rule called E6B :smiley:

Guess I am not one of those many pilots. :open_mouth:

Flight planner anybody? Looking to compare airspeed and ground speed based on live weather data.

You may want to mosey on over to … end=MSGend

While not exactly designed for the novice since it is designed from a pilots point of view, it will give you all you want about groundspeed based on current weather conditions and gives you a nice profile on what altitude would give you the best tail winds after you request the navlog.

And I stand by the reasonable accuracy of this website since it is one of my many tools used when I am not home to use my computer based flight planner such as AOPA or Voyager.

Alot of nice resources at for those that plan “on the road” and it does print out a real nice “passenger briefing” from the link on the left side.

Of course, when getting my formal weather briefing, I use DUATS and file accordingly based on all available resources which one of mine would be the above link since it does a wonderful job with winds aloft and does the math for groundspeed.

Thread drifting below.

Just curious, does anybody practice the art of dead reckoning (something that was part of my VFR flight training) after getting their pilots license with the advent of handheld GPS’s?

With my onboard GPS Garmin 430, and handheld, can’t imagine the likelyhood of both going out simultaneously (unless there was a RAIM) AND an electrical failure in my plane disabling the rest of my nav equipment for that need of dead reckoning. Of course, I’d really be up that creek since I don’t wear a watch and I think the clock in my ship runs off the ships electrical power.

(who lives in MS delineated by Dami’s “disclaimer”)



I’m one of them. I much prefer the electronic version but I’ve used the whiz wheel recently too.

The E-6B is an amazing device when you take into consideration it’s age and simplicity.

I’ve used and I like it. When I file a vfr trip on fltplan and call ground for taxi they have the plan up and almost treat me like ifr and offer a code for flight following.

I do. Fortunately we have 300+ days of sunny, clear weather and lots of unique terrain features. I’ve only flown once with a GPS. I’m thinking about getting a hand held unit, but not going to rush into anything. :stuck_out_tongue:

I don’t think anyone needed to plot the coordinates!


Oh kewl, you would be the first one I have met since the advent of GPS :smiley:

This is not to say it’s not being taught these a’ways, but seems like based on my observations, once the pilot finishes his checkride, that whiz wheel ends up being a weight and balance issue rather then a practical tool it really is designed to be.

Since getting my instrument, I haven’t really even filled out a paper flight nav log much less even consider using the whiz wheel, so I guess I better hope the lights don’t go out :laughing:

Yes, you are so right Ironic thing was for the whiz wheel, took me forever and a day to put it all together with the inner and outer wheel, but when it did, that light bulb burned bright and proud! And when it did click, I for the life of me kept asking, why was it so hard to learn!

You are a little braver then me. I have not filed a flight plan through a third party website like Fltpln or AOPA, just through DUATS whether it be web based or my flight planning software on my home computer.

Are you flying by pilotage or dead reckoning? Sounds like pilotage what you describe above using terrain features. Dead reckoning is strictly by time and heading.

Yeah, you are right, but figured that I don’t need to hide behind long and lat coordinates, saves the new people from looking up the coordinates.

Bad thing is, there is at least one other Flight Aware person that is based within those lat long confines, so naturally his disclaimer incorrectly excludes other flight Aware Members that are within those confines. Of course, I can let them speak for themselves but just a typical inaccurate posting by the individual in question.

Unless he has that much distaste for MS, dunno. 8)




Sorry I wasn’t specific. I was trying to point out the conditions here are different then Mississippi. We have clear air and lots of local and regional reference points making it harder to get lost if you know the lay of the land. I’ve done alot of both. Specifically I’ve used DR as recently as 9/12/07. I might do it again soon. I think it’s fun. :open_mouth: