July 2017 Rangeplot

 from Planeplotter
 

click to enlarge

 and from Virtual Radar Server

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July's results show some significant increases in most directions. The gain settings were the same as June's, but the distances were greater. Some of the increase can be explained by more aircraft at higher altitudes in more directions, however some was purely weather based.
During the month, there were several large storms that passed through Saskatchewan. I've noticed that during storms or in the early morning after a storm, when the air is very humid, my reception range expands. In some cases, whether by reflection, conduction, tropospheric ducting, or some other freak of nature, I've received aircraft at altitudes and distances that should be technically impossible. I'll add a separate post with more details.
 

Live view of Saskatchewan skies

Courtesy of opensky-network.org. You can mouse-over each aircraft for additional details, and if you click on the Opensky logo, the link will take you to their website.

 

 

 

June 2017 Rangeplot

 from Planeplotter
 

(click to enlarge)

 

and from Virtual Radar Server

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The pattern of flights from month to month doesn't appear to change very much. They generally follow the same routes, however in June there were many more flights ranging from 450 to 500 flights per day. Sometimes the same aircraft can be seen multiple times in the same day, such as those that arrive from Europe early in the day, and then return in the evening.

 

 

 

 

May 2017 Rangeplot

 from Planeplotter
 

(click to enlarge)

 

and from Virtual Radar Server

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In May, I started feeding to the Opensky Network, based in Switzerland. A joint project of two universities, they apparently are the only service that archives the tracks and makes them available for research purposes. As far as I can tell, we're the only Saskatchewan feeder.

The live view of Saskatchewan skies has been moved to the June Rangeplot posting.






 

 

 

April 2017 Rangeplot

 from Planeplotter

(click to enlarge)

 

and from Virtual Radar Server

(click to enlarge)

 

In April, summer flight schedules began, which brought some airlines that I haven't seen here before. The Polish airline LOT, has started regular service from Warsaw to Los Angeles several times per week and Austrian Airlines is serving Los Angeles from Vienna.

Boeing continues deliveries of their newest 737-800 aircraft, and many commercial airlines worldwide have ordered them. In April both Ryanair(Ireland) and Egypt Air took delivery of these brand new aircraft, and each of them flew over Saskatchewan. Ryanair has been flying direct from Boeing Field in Washington to Dublin, while Egyptair has been making a stop in Iceland before continuing on to Cairo.
It appears that the transponders in these aircraft are particularly strong - the two westernmost points on the rangeplot (south of Red Deer and south of Calgary) were both from new 737-800s being delivered.

 

 

March 2017 Rangeplot

 from Planeplotter




(click to enlarge)

 

and from Virtual Radar Server

(click to enlarge)

At the beginning of March it was time to upgrade some of the software components used to track flights and generate these images. I upgraded Planeplotter and each instance of Dump1090-Mutability. Somehow I messed up the Planeplotter upgrade and not all of the background map tiles loaded, and at the same time, I managed to chop-off the top and bottom of the aircraft trails. With the restart at the beginning of April, the problem seems to be solved.

 

Spikes on the chart

Sometimes a garbled signal will be received from an aircraft and is decoded with an incorrect position. At other times, an aircraft may have a defect in its transponder that is causing it to occasionally transmit incorrect positions. These will often appear as random single spikes in the monthly chart on Virtual Radar Server, and as much as the software will try to apply some logic and filter them out, some of the false positions remain. Of course, if conditions are 'just right', a perfectly valid spike may appear, however after checking the logs, that large spike into Manitoba does not appear to be a valid one.

 

 

 

February 2017 Rangeplot

 from Planeplotter

 

 (click to enlarge)

 

and from Virtual Radar Server
 

(click to enlarge)

 

Occasionally, there will be brief times when atmospheric conditions are 'just right' and aircraft that would normally be out-of-range, can be received. For some reason that I'm not able to explain, this happens most frequently to the south-east, as can be seen in the plot from Virtual Radar Server. The red rings are 100 kilometers apart, so that would place this particular distance at well over 500 kilometers.

 

Outdoor temperatures during February ranged from +8C to -30C. During this month the core temperature of the OrangePi PC out on the roof varied from +25C to -4C and both it and the Flightaware ProStickPlus receiver connected to it continued to perform flawlessly.

 

 

 

 

 

 

January 2017 Rangeplot

from Planeplotter



(click to enlarge)

 

and from Virtual Radar Server

 

(click to enlarge)

The maximum distance recorded during the month was 247 nautical miles (457 kilometers)

These distances were achieved with the gain set to 28db in the Dump1090-mutability decoding software.

 

 

(click to enlarge)

 

During the first half of January, outdoor temperatures dropped to -34C with wind chills reaching -47C. The core temperature of the Orange Pi PC outside on the roof reached a low of only -16C. While unable to directly measure the temperature of the Flightaware ProStickPlus, it also would have been very cold but performed flawlessly. Sensitivity of the ProStickPlus appeared to improve as the temperature dropped. I need to start planning to add some venting to prevent the electronics from overheating in the summer months.

 

New Indoor Antenna with a Tiny Receiver

1090mhz Bi-Quad 

(click to enlarge)

Built this over the holidays to see how it might perform.  The back panel is about 11 by 9 inches of scrap copper-sheet mounted on a short aluminum angle with four small bolts. The angle is in turn held onto an indoor second-floor railing with a couple of zip ties.

The center stub is a short length of LDF2-50 Heliax and the feedline is 1.5 meters of RG402 semi-rigid coax. The receiver is a FlightAware ProStick Plus connected to a Nexx WT3020 mini-router running OpenWRT with Dump1090-mutability, which then feeds an instance of Virtual Radar Server.

WT3020 mini-router and FlightAware ProStick Plus

These two devices together are less than 6 inches wide and draw less than 0.5 amp between them, and seem to perform quite well with the bi-quad antenna. (The front connectors on the router are WAN, LAN and power, with the USB connector on the side)

 

Here is a 24 hour plot from this combination. The antenna is indoors, facing S-SW, and has not yet been adjusted or fine-tuned. Although bi-quad antennas typically have a back lobe, I'm surprised by how much is received from behind the antenna. Perhaps after adjustments, that will improve.

24 hour range plot 

(click to enlarge)

 Red rings are 100km apart.

 Currently aimed S-SW, and reaching about 375km.

 

 

December 2016 Rangeplot

from Planeplotter

 

(click to enlarge)

 

and from Virtual Radar Server

 

(click to enlarge)

 

Range rings are back to being in kilometers, with the outermost red ring being 400kms.

 

The aircraft up near Cold Lake at 4225 feet is not real. It is an artifact from a garbled signal received a few days ago, that didn't clear out properly.