Emirates flight EK421 on 1st June 2022 from Perth, Australia to Dubai, UAE took 10 hours 31 minutes. The aircraft operating this flight was a Boeing 777-300ER and departed Perth International Airport at 14:26 UTC arriving in Dubai International Airport at 00:57 UTC.
The Emirates flight EK421 on 1st June 2022 was successfully detected and tracked over the Indian Ocean. 17 position indicators and 46 progress indicators allowed flight tracking over a 3 hour period. The intersections of multiple WSPRnet links align with the estimated position of the Boeing 777-300ER aircraft and these WSPRnet links show SNR, drift or dual anomalies for the particular WSPRnet links involved within the 3 hour analysis time frame. These indicators allow an absolute determination of the aircraft’s position at 17 points in time and a likely determination of the aircraft’s position at 46 further points in time. The resulting aircraft track aligns with the ADS-B data from FlightAware where available.
The flight route is almost entirely over the Indian Ocean and at 18:46 UTC crosses the estimated flight path of MH370 which disappeared on 8th March 2014 in the Southern Indian Ocean. ADS-B data from FlightAware is available for almost 6 hours of the flight in 3 parts, firstly near Australia, secondly near Sri Lanka and India and finally near Oman. There is a total gap of 4.6 hours over the Indian Ocean where the aircraft is out of range of land based ADS-B receivers.
The paper can be downloaded here
@All,
A message from the MH370 next of kin:
“You have put in an astounding amount of work into tracking MH370!!
We thank you for your time and effort.
We are praying OI will find the plane!!
We have posted the paper on the MH370 Families FB Page.”
@All,
In our paper we cite Harry Nykvist (Nyquist US).
According to the IEEE paper linked below Harry Nyqvist changed his name to Harry Nyquist upon arrival in the US:
“Harry Theodor Nykvist was born on February 7, 1889 in Nilsby, a small village in Sweden. He was the fourth child among eight siblings. His father, Lars Jonsson Nykvist, was a shoemaker, his grandfather was a watchmaker.”
“In 1907 he left Sweden, landed in Boston, changed spelling of his family name to Nyquist.”
https://ieeexplore.ieee.org/document/9722940
@All,
A new article by Geoffrey Thomas of airlineratings.com on the WSPR technology:
https://www.airlineratings.com/news/industry-news/mh370-tracking-expert-demonstrates-technology/
@All,
Another article by Geoffrey Thomas of airlineratings.com asking why wouldn’t Malaysia want to find MH370:
https://www.airlineratings.com/news/why-wouldnt-malaysia-want-to-find-mh370/
Assuming that power to the Satellite Data Unit on mh370 was lost sometime after 17:21 UTC and then restored shortly before 28:25 UTC, would the SDU perform more quickly after a hard reboot, like with a personal computer? If ACARS were no longer reporting to the SDU, would this fact decrease the time in which the plane’s SDU would receive, process and reply to a signal from the satellite? Finally, approximately how many kilometers difference in the distance of the plane to the satellite are there for every 100 microseconds? Meaning, if the SDU spent only 2,700 microseconds receiving, processing and replying to a signal from the satellite, instead of the assumed 4,700 or so microseconds, how many more kilometers would we expect the airplane to be from the satellite at the time of the interrogation?
@Jennifer,
Welcome to the blog!
You ask: “would the SDU perform more quickly after a hard reboot, like with a personal computer?” and “would this fact decrease the time in which the plane’s SDU would receive, process and reply to a signal from the satellite?” and “approximately how many kilometres difference in the distance of the plane to the satellite are there for every 100 microseconds?” and “how many more kilometres would we expect the airplane to be from the satellite at the time of the interrogation?”
The Satellite Data Unit (SDU) is a part of the satellite communications system. It is not designed for navigation, but for communication. The communication relies on a very stable temperature controlled oscillator. The transmissions between the ground station in Perth, Australia and the Inmarsat satellite over the Indian Ocean and the MH370 aircraft are all at the speed of light and at various set frequencies. The frequency bands and the speed of light do not change following a reboot of the SDU.
The Burst Timing Offset (BTO) is measured at the ground station and allows us to calculate the distance from the satellite to the aircraft, as we know the distance from the ground station to the satellite at each point in time.
The Burst Frequency Offset (BFO) is also measured at the ground station and allows us to calculate the relative velocity between the satellite and the aircraft, as we know the velocity of the satellite, the L-Band uplink frequency, the C-Band downlink frequency, the SDU aircraft doppler compensation, the aircraft satellite uplink doppler, the ground station satellite downlink doppler, the Enhanced Automatic Frequency Control (EAFC) effect and the eclipse effect.
Following a reboot of the SDU the temperature controlled oscillator which is in an oven will settle at the correct operating temperature and a very stable operating frequency. If this were not the case, then the handshake signals to establish a communication between the aircraft and the ground station via the satellite would not work.
At 18:25:27.421 UTC the SDU issued a Log-On request. This was answered at 18:25:28.852 UTC with a Log-Confirm. Further channel control signals were received by the SDU and at 18:25:34.461 UTC the SDU sent a Log-On Acknowledge. A total of 26 signals were exchanged culminating in a further acknowledgement at 18:28:14.904 UTC. We know that the SDU was working normally.
At 18:39:52.907 UTC the SDU received a call announcement. Although the call was unanswered, a total of 92 signals were exchanged showing the SDU was working normally.
A further set of handshake signals and a second call announcement comprising a total of another 71 signals being exchanged and showing the SDU was working normally up until 8th March 2014 00:19:38.407 UTC.
The BTO and BFO data are reliable and give the correct distance of the aircraft from the satellite and the correct relative velocity between the aircraft and satellite. In answer to your specific question there are approximately 15 kilometres difference in the distance of the plane to the satellite for every 100 microseconds.