Introduction

The SFO Near Live Flight Tracks Display allows you to watch the movement of flights and air traffic patterns currently in use within the Bay Area. This map will show flight tracks of aircraft arriving and departing from SFO, Oakland, and San Jose Airport and other nearby general aviation airports.

These flight tracks, although taken from actual radar data, are not in real time. There is a delay of ten minutes, as indicated in the lower left corner of the map window.

This web page gives instructions on launching the flight track display and all of the features of the display:

Launching the Display

To start the display, click on one of the green aircraft buttons on the main webpage. The two buttons look like:

If you have a fast Internet connection (e.g., Cable Modem, DSL, T1), click on the left button. If you have a slower connection (e.g., dialup 56K) click on the right button.

The only difference between the two buttons is that the "low speed connection" button will cause the map display to initially show a lower-quality street map, whereas the "high speed connection" initially shows a nicer, high-quality street map. The higher quality maps take longer to download, and hence a higher speed connection is better. Once you launch either version, you can switch back and forth between high quality and low quality maps, if desired (see Map Type below).

Note, if you bring up the main web page and do NOT see the two green aircraft images, please wait a few minutes (if your connection is slow) for the program to load across the Internet. If you've waited but the images still do not appear, you may have problem with the configuration of your web browser. See the help page for more information on troubleshooting this problem.

Once you click on the green aircraft image, the map display will appear on your screen in a separate window. Depending upon the speed of your Internet connection, this can take anywhere from a few seconds to a minute. When the map appears, the green aircraft image on the main web page will turn red:

This means the display is up and operating. If you click on the red aircraft image, the map display will disappear and the image will turn green again. (You can also exit the map display from the map window itself, like any other standard window.)

Navigating the Map

The Map Display contains a base map of bay Area:

Initially, the map is centered around San Francisco International Airport, but you can pan and zoom to see different areas of the map:

To navigate, double-click anywhere on the map to recenter. Then, use the "Zoom" pull-down choice (on the bottom left corner of the window) to zoom in and out. You can also use the scrollbars to slide left/right and up/down, but you'll find that double-clicking and then re-zooming is the faster way to navigate the map.

Another way to re-center and zoom is to click the Right Mouse Button over the map. This will give you a pop-up menu which includes:

  • Re-center the map at the current mouse location



  • Zoom in/out



  • Re-center the map AND Zoom in/out



You'll note that the map window, and all windows that appear as part of this display, show the words "Warning: Applet Window" at the bottom. This is a standard security precaution built into most browsers (like Internet Explorer and Netscape) to warn you that this is an Internet window, not a normal program on your PC. You can ignore this warning.

Near-Live Flight Tracks

Within a few moments after the map display appears, you should begin to see flights move around the map. These flights depict the flight traffic in near-real time, delayed by 10 minutes. If you look at the date and time depicted in the bottom left corner of the window, you will notice that it remains 10 minutes prior to the current time. The time is always represented in the Pacific (California) time zone, regardless of where your computer resides.

The data is processed from a radar feed, which gives a fairly accurate account of aircraft position and altitude. However, radar data can contain anomalies such as spikes and jags and reflections, which have been corrected as much as possible before being displayed on your screen. Nevertheless, if you see occasional odd jags in the flight tracks, these are likely radar anomalies and NOT true depictions of the flight track. These anomalies are not common, and will mostly likely occur when the flights are nearer to the ground, where radar data can more easily reflect off of nearby buildings.

Each flight is colored based on the type of operation:

GREEN Aircraft are those that have been detected as departing from an airport (i.e., their altitude is rising instead of falling).
RED Aircraft are those that have been detected as arriving at an airport (i.e., their altitude is falling instead of rising).
WHITE Aircraft are "overflights", i.e., aircraft that have been detected as flying over the area, not landing or departing. They usually fly at a significantly higher altitude than the green and red flights.
BLACK Aircraft are those identified as "General Aviation" aircraft. These are identified based on a standard general aviation "transponder" code. They are usually smaller aircraft, not associated with any airline. No flight information (airline, aircraft, etc.) is known for general aviation flights.
ORANGE Aircraft are those that cannot be identified as being an arrival, departure, overflight, general aviation, or helicopter. Often these are general aviation aircraft, and in some cases the altitude is not reported and thus its flight type cannot be determined.
Helicopters on the display are those that have been detected as being helicopters. There is no particular information from the radar that identifies helicopter vs. non-helicopter, so the flight pattern is analyzed (based on its speed, altitude, turning pattern) and the flight is "detected" as being a helicopter based on these rules. For this reason, you may sometimes see orange aircraft "turn into" helicopters and vice versa, as the program tries its best to determine the type of flight. Since helicopters can indeed fly in a pattern similar to a small general aviation aircraft, some black/green/red/orange aircraft on the display may indeed be helicopters that have not been detected as such.

You'll note that if you move the mouse over a moving aircraft, the altitude of the flight and its current speed will appear on the bottom of the screen:

The altitude is shown in terms of "msl", i.e., the number of feet above sea level. The speed is given in knots.

Flight Information Window

If you click on a moving aircraft (the aircraft image, not the "trail"), the aircraft will turn yellow and a "Flight Information" window will appear. This window gives information about this flight and depicts, in a bar chart, the altitude and speed:

The blue bar chart shows the altitude between 0 and 10,000 feet. (If the aircraft climbs above 10,000 feet, the bar will turn cyan-colored and show the altitude between 0 and 40,000 feet). The yellow bar chart shows the speed between 0 and 500 knots. Once you have clicked on the flight, the Flight Information window will continue to track this flight (i.e., the bar charts will update as the flight moves along the screen).

The top portion of the screen shows the logo for the airline, as well as:

  • Operation: Departure or Arrival
  • Time of Departure or Arrival
  • Airport of Departure or Arrival
  • Runway assigned
  • Airline Code (e.g., DAL for Delta Airlines)
  • Flight (e.g., DAL1790 for Delta Airlines 1790)
  • Equipment type (e.g., B737 for Boeing 737)
  • Class (Jet or Propeller)
  • Destination Airport (e.g., LAX)
IMPORTANT Note about Flight Information: The information described above is only available the day after the flight operated. This is due to FAA restrictions on this information. Therefore, if you click on a 10-minuted delayed flight, you will not see any flight information. You will still see the altitude and speed, but the associated information will not be available until the next day.

Via the Playback feature, described below, you can play back flights for any time period in the previous seven days. Flights that are played back for any day except the current day should have this flight information available, and thus it will appear in the Flight Information window.

Also note that helicopters and most smaller general aviation aircraft will not have this information available.

Only one Flight Information Window can be up at one time, so if you click on another flight the window will update with the new information.

Playback Control

From the window's menus, choose Playback Control:

You can also choose by clicking the Right Mouse Button over the map and choosing Playback Control:

This will bring up the Playback Control window:

You will notice that the date and time displayed in this window will match the date and time that is displayed on the bottom of the main map window: it depicts the date and time of the information currently being displayed (in the picture above, this is shown as date 4/19/02, 1:16:01 PM). Underneath the date is a white box showing the number of minutes the playback is delayed from real-time. I.e., the map is showing flights delayed by 10 minutes.

Using this display, you can stop the current display and begin playing back flights from any time in the previous 7 days. You can do this in one of two ways:

  • By specifying a date and time to begin playback, or
  • By specifying a number of minutes/seconds to delay from real-time

First, you must PAUSE the current display. To do this, click the PAUSE button. This will cause the other two buttons to become available: RESUME AT DATE/TIME and RESUME RELATIVE TO:

To begin playing back at a specified date and time, type in the desired date (in the form of MM/DD/YY), the desired time (HH:MM:SS), and choose AM or PM. (If you use military time, e.g., 14:00:00, it will automatically change it to clock time, e.g., 2:00:00 PM.)

Once you have entered the desired date and time, click the RESUME AT DATE/TIME button. The map will now begin showing flights beginning at that time, and the date/time in this window (and on the main map window) will begin updating second-by-second based on the new starting time. Also, note that the "delay" time (which was initially set to 10 minutes) automatically changes to the new delay amount. E.g., if you typed in a date that was exactly 24 hours ago, the delay time will show 24:00:00.

The other means to playback flights is to specify a new "delay" amount instead of an exact date and time. For example, if you just want to see flights delayed by one hour ago (instead of the default 10 minutes), enter "1:00:00" in the bottom white box and click on RESUME RELATIVE TO.

Every time you wish to change the playback, you must first click PAUSE to pause the current display. Every time a new playback begins, the current flights on the map are erased. In addition, you can erase the flights directly by clicking on the CLEAR FLIGHTS button on this display. This is useful if you wish to pause all flights and then clear all flights to view the map only (or to view sets of flight tracks, a feature which is described below).

Display Tracks

Another way to look at flight tracks is to see groups of tracks at once, instead of watching them fly in an animated fashion. In this manner, you can see, for example, all of the flight tracks over the course of an hour grouped together. To use this feature, choose the Display Tracks feature from the Tracks Menu:

You can also choose by clicking the Right Mouse Button over the map and choosing Display Tracks:

This will launch the Display Tracks window:

You'll note that it looks similar to the Playback Control window, but the buttons and the fields perform different functions. By typing in the desired date, start time, and duration, you can "fetch" flight tracks and have them displayed on the map. In the above example, the Display Tracks window is set up to view 30 minutes ("0:30:00") of flight tracks starting at 4/15/02 and 11:00:00 A.M. Click on the SHOW TRACKS button to begin showing the tracks. After doing so, the display will change to:

This indicates that the flights are being fetched and, when complete, will appear on the map. The default span is 15 minutes, and it is not recommended to request quantities larger than an hour or two, because of the very large amount of data needed to sent across the Internet. A request for 15 minutes of flight tracks can take anywhere from 1 to 5 minutes to complete, depending upon the speed of your Internet connection.

When the fetch is complete, the tracks are displayed on the screen, shown as a set of green, red, white, blue, and white lines (depending on the type of flight, described above). Note that the live animated display is still functioning at the same time. If you wish to view flight tracks without seeing the animated flights, use the Playback Control to PAUSE and CLEAR the animated flights.

Once the tracks are displayed, you can click on any flight and see the standard Flight Information Window:

As before, not all flights have flight information, and flight information is not available until a full day after the flight. Also, since this is a static flight track and not an animated playback, there is no altitude/speed bar chart shown.

Address Lookup

The Address Lookup feature allows you to type in any address and see the location displayed on the map. The display will also show the distance between any address and any flight. To begin, choose Address Lookup from the Address Menu:

You can also choose by clicking the Right Mouse Button over the map and choosing Address Lookup:

This will launch the Address Lookup Window, which looks like;

In the top portion of the screen, you can type in any address. The standard format is:

    Street Address, City, State

The State is optional, as it will assume California.

Every address that is typed in is added to a pull-down list, shown directly below the place where the address is typed in. This is a "shortcut" so you don't have to repeatedly re-type the same address over and over. Once an address is typed once, you can simply pick it from the list to see that address again.

Note that the pull-down list already has one entry:

    825 Southwood Drive, South San Francisco.

This is simply to provide an example of a valid address. You can pick this address from the pull-down list to see this address.

The Address Lookup feature is also aware of many landmarks and their acronyms. E.g., typing "SFO" will find San Francisco International Airport.

Note that once the address is typed in and the "Look up Address" button is clicked (or simply the Enter Key pressed), a list of matching addresses will appear below. In the example above, when SFO was typed, the list showed one entry:

    SFO (San Francisco Internation Airport), California

If there were multiple matches for the address typed, they would appear in the list and you can choose from among them. Note that once the address is entered, a green "house" appears on the map at the address location.

Because (in the example) the "Re-center on Lookup" check-box was checked, the map automatically recentered to the desired address, as shown in the picture above (the green house appeared at SFO, and the map recentered there). If "Re-center on Lookup" is NOT checked, the house will still appear on the map but the map will not automatically re-center to focus on the house. At any time you can recenter the map on the house by clicking the "Re-center Map" button.

The house will remain on the map, even after the Address Lookup window is closed, until you click on the "Remove from Map" button.

If you click on the map while the Address Lookup Window is up, the Address Lookup will display the distance from the mouse-click to the address (in miles, or if less than in mile it will show the distance in feet). If you click on an aircraft, the aircraft window will show the distance from the aircraft, as well as the aircraft's altitude.

(Note that this distance is "ground distance", NOT a three-dimensional slant-range distance.)

Also, when you click on a flight while an address is present on the map (e.g., while there is a "house" on the map), the Flight Information window will display a bar chart of the distance between the aircraft and the house (again, this is a two-dimensional ground distance).

The red bar chart on the bottom right shows the distance from the address in miles, on a scale from 0 to 5. If the aircraft is more than 5 miles from the house, then the bar will turn blue and show the distance on a scale from 0 to 50 miles.

Note that the "yellow" aircraft is the one selected by the mouse.

Contours

The Contours Menu allows you to view Noise Contours for SFO Airport. When choosing the view the contours:

You will see three colored lines around SFO:

representing the 65, 70, and 75 db CNEL Contours. For more information about these contours, please contact the SFO Noise Abatement Office (see: http://www.flyquietsfo.com/SFO/ContactaUs.htm ).

Resize the Display

Like any standard window, you can resize the map display by dragging the corner of the window. You can also resize the display to specific sizes via the Resize menu:

This is a useful menu item if your screen is very small and by default the map appears too large (especially on a Macintosh, where the "resize corner" may initially appear off screen).

Map Type

Via the Map Type Menu choice:

or alternately by clicking the Right Mouse Button over the map:

You can switch between the high-resolution maps and the low-resolution maps. The high-resolution maps contain more detail, but they take longer to download across the Internet and may be cumbersome to use if you are using a dialup Internet link.

This is an example of a low-resolution map image:

Map Background & Contrast

The base map can be altered to be shown in black and white instead of color, and can be brightened or dimmed:

These features are also available by clicking the Right Mouse Button on the map:

Changing the color and contrast can sometimes make other object (planes, houses, tracks) easier to see. Note, though, that the display takes slightly longer to refresh when in black/white or dim/bright mode, thus making the display slower.

Help/Status

The Help Menu provides a link to this Instruction Webpage:

It also provide a Status Window:

The Status Window gives information about the program's ability to collect flight track data for display on your computer, and indicates if there are any firewall or other Internet issues. This Status Window will pop-up automatically if there is a problem in getting flight data to display.

The Trouble Shoot choice from the Help Menu:

brings up a webpage with tips on how to resolve typical browser problems that may prevent the program from running properly.