New to the forums though have been using the site for months and find it incredibly useful and informative, especially for a former ATC Approach Controller. Recently I've noticed contained in the aircraft data window that pops up on the left side of the display that winds aloft show up on most if not all airliners and a good number of GA aircraft. It also appears that if you go west of say the Lynchburg, VA., area on a north/south line east of Lynchburg you'll see the wind, west of that line there is not winds aloft data. Curious if anyone else noticed this and if so is it something being added to the program slowly or is this a known anomaly? Thanks for your information and seeya on the boards.
Hello! Happy to see an ex-ATC Controller, yall are an interesting group of people. If I'm remembering correctly, wind speed and direction data aren't constantly broadcast- only broadcast if ATC interrogates the transponder for it. Not sure what the boundary in central VA would be, maybe it's just a distance from the larger airports on the eastern seaboard there.
Not sure exactly how to take that comment, but yes we are a very "interesting group of people"!!! Yeah, strange location for a boundary to be established. I'd have thought that say every SWA jet had the same software which they most likely do as an example, they'd broadcast the same data no matter where they were flying. You can see all the other information from the MCP that the crew has set, the wind information is included in their FMC so thus my curiousity.
Different ATC radars in the US either interrogate the needed stuff or they don't. (not sure why the differences, maybe just older equipment or it could be how it's configured) https://github.com/wiedehopf/readsb/blob/dev/README-json.md wd, ws: wind direction and wind speed are calculated from ground track, true heading, true airspeed and ground speed oat, tat: outer/static air temperature and total air temperature are calculated from mach number and true airspeed (typically somewhat inaccurate at lower altitudes / mach numbers below 0.5, calculation is inhibited for mach < 0.395)
Really funny that when I look right now at the same areas I've been seeing with wind information showing up, nothing is showing up now with winds. HMMMM crazy!! The software that the ATC RADAR is using is from multiple sources to include long range, short range, ADS-B data from ground stations etc., and it is available all across the U.S. So the data I've seen from the MIA area should be the same I see in the Houston area since both TRACON's are utilizing the same software in STARS.
But does that software control interrogations? Is Indicated Airspeed always shown or only in certain circumstances? Not all transponders are capable but most airliners are capable. Also check for True Airspeed (as described that is required among other things for the winds to be calculated)
Wish I knew the answers to those questions, but indicated airspeed was never shown on the controllers display only ground speed on the data block when I retired back in 2013. With the ADS-B software that was added back in 2012 the newest update to the software was supposed to give more information from the MCP though do not know if it was ever implemented. I'm just more curious about this site seemingly having the winds aloft available east of a line around Lynchburg and nothing west of it, though again this morning nothing is showing up for winds.
I programmed "this site" or at the very least this feature. And as i mentioned we can only calculate the winds if ATC interrogates for true airspeed. So that's the answer, we can't interrogate aircraft ourselves now do we I guess the question becomes why different ATC systems interrogate differently across the US. Over Europe you get winds very consistently even on approach to landing at quite a few airports. So it's not just that west / east in the US, check aircraft landing JFK, they often lose true airspeed and that stuff when they go from the center to New York approach.
Well it's all quite interesting to me and makes no sense why one day you see the winds east of that imaginary line and never anything west of it, almost like there is a block of data from those flights. Also, why some days you see the wind data and other days such as today not one flight has it displayed. As for center to approach, different software is used for enroute as opposed to terminal as well as different displays to the controller. Heck I am not even sure the center uses any ADS-B information, but in the approach control world we got a refresh rate down from 4.8 seconds to 1 second when we instituted ADS-B. Thanks for your info.
I have no idea what the f the FAA is doing. Seems today we don't have those data in the US at all. Radars go into holiday mode ..... Our system treats all the planes the same so if you want to check our system check the winds displayed for airliners over Germany, those always work. Maybe the FAA is doing some testing to see if the extra messages are an issue in regards to 1090 MHz saturation? Doing comparisons between areas? Anyhow it's all quite strange indeed.
