Hey all, I'm currently doing a flight from Boston to Heathrow, 747-400x. I just noticed my ground speed was 590 knots...which is faster than I've gone in a long time (I've mostly been in the NGX). I'm using real time weather (ASE) at FL340 and a CI of 150. I'd like this thread to become something like http://www.groundspeedrecords.com/. regards Edit:PS I later got to 605 between Newfoundland and Iceland. FL350.

Edited September 30, 201114 yr by cvhmaverick

There is a website with groundspeed records for IVAO: http://www.focusdesigns.org/ivaogroundpeeds Dion Mollert

http://www.groundspeedrecords.com/ PS - If the owner of the C172 that got 325kts over the ground is on this forum, please PM me. I'm looking to buy. :)

And that C172 with 325kt of groundspeed? They where riding a tornado?

I'm curious about the 752 knot 747-400, that is faster than the speed of sound (in theory), but it has a subsonic airspeed. I'm slightly confounded by this. That is pretty cool.....Luke Stevens

I'm curious about the 752 knot 747-400, that is faster than the speed of sound (in theory), but it has a subsonic airspeed. I'm slightly confounded by this. That is pretty cool..... Luke Stevens

What's confounding about it?

I'm curious about the 752 knot 747-400, that is faster than the speed of sound (in theory), but it has a subsonic airspeed. I'm slightly confounded by this. That is pretty cool.....Luke Stevens

Now, the speed of sound is based off barometric pressure, temperature and humidity. Sound are vibrations traveling through the air, now air is a fluid, like water, and the conditions of temperature and such change the way these vibrations travel. So, although yes his groundspeed is a speed that is at sometimes supersonic, at this time, it probably wasn't. Because of all the variables, there is no set speed at which sound travels. There's you're answer.

At cruise altitude the speed of sound is in the vicinity of 570 kts (air speed) depending on atmospheric conditions as mentioned above. His airspeed is 497, well below that.

Of course the airspeed was subsonic for the assumed atmospheric conditions, I aknowledged that in my post. I was amazed this was the case. I'm a chef not a scientist.....

I'm curious about the 752 knot 747-400, that is faster than the speed of sound (in theory), but it has a subsonic airspeed. I'm slightly confounded by this. That is pretty cool..... Luke Stevens

Wow!! That guy had a 213 knot tail wind pushing him along!!!