In this case study we analyse the tragic flight of a Cessna 551 Citation II/SP registration OE-FGR, which crashed after fuel exhaustion into the Baltic Sea off the coast of Latvia on Sunday 4th September 2022.
The aircraft departed Jerez-La Parra Airport (XRY) in Spain at 12:56 UTC, en route to Cologne Airport (CGN) in Germany. The aircraft continued at FL360 through German and Swedish airspace. The aircraft was not reachable by air traffic control authorities for some time. French, German and Danish fighter jets were in turn dispatched to follow the aircraft. Reportedly the pilots could not see anyone in the cockpit of the aircraft.
This case study is similar to the tragic flight of MH370 in as much as the aircraft flew until fuel exhaustion and then crashed into the sea. The airspace around the aircraft was cleared of other air traffic over the Baltic Sea with the exception of the fighter jet assigned to follow and observe the Cessna.
The analysis in the report supports our previous belief that using WSPRnet data to detect and track MH370 together with the Boeing 777-200ER performance data and the Inmarsat satellite data provides a reliable method to determine the crash location.
The case study can be downloaded here
Updated 30th October 2022 to include on page 1: “The last 22 minutes of flight were chosen because the airspace in the vicinity of Cessna was cleared of other traffic. This was not the case for the flight before reaching the Baltic Sea.”
@All,
Geoffrey Thomas has published a new article on MH370 and WSPRnet technology:
https://www.airlineratings.com/news/mh370-new-research-paper-confirms-wsprnet-tracking-technology/
The authors said that they “have demonstrated how aircraft can be detected and tracked both in the cruise phase of a flight in straight and level flight as well as in the descent phase whilst descending and turning.
The authors also investigated alternative hypotheses and anomalies in relationship to WSPRnet links and said that while the WSPRnet data was noisy, with care it is possible to extract useful information.
They add: “The analysis in the report supports our previous belief that using WSPRnet data to detect and track MH370 together with the Boeing 777-200ER performance data and the Inmarsat satellite data provides a reliable method to determine the crash location.
@All,
Prof. Simon Maskell asked us to produce some statistics comparing the latest case study to previous findings on MH370.
Case Study Cessna OE-FGR.
183 Observations.
119 Unique Triples (Tx-Rx-Frequency).
109 Unique WSPR Links (Tx-Rx).
78 Unique Tx.
78 Unique Rx.
Mean Great Circle Distance Tx to Aircraft = 2,592 km (Min. 284 km, Max. 10,273 km).
Mean Great Circle Distance Tx to Rx = 1,633 km (Min. 175 km, Max. 15,567 km).
Case Study MH370.
187 Observations.
156 Unique WSPR Links (Tx-Rx).
92 Unique Tx.
79 Unique Rx.
Mean Great Circle Distance Tx to Aircraft = 13,676 km (Min. 1102 km, Max. 19,868 km).
Mean Great Circle Distance Tx to Rx = 4,430 km (Min. 510 km, Max. 16,527 km)*.
* = only WSPRnet Links with Tx to Rx Great Circle Distance ≥ 500 km were considered, hence the Min. is 510 km.
@All,
There were 23,871 WSPRnet links in the 24 hour period with a propagation ≥ 15,000 km on 4th September 2022:
https://www.dropbox.com/s/yugipq1ccmegj66/Count%20WSPRnet%20Links%20%E2%89%A5%2015%2C000%20km.png?dl=0
There were 5,596 WSPRnet links from transmitter call sign VK3MO in a 24 hour period with a propagation ≥ 15,000 km on 4th September 2022:
https://www.dropbox.com/s/9k6gb3bfg6d7r7n/Count%20Tx%20%E2%89%A5%2015%2C000%20km.png?dl=0
The greatest propagation distance recorded in the 24 hour period on 4th September 2022 was 19,769 km between ZL2TLF and EA8CHC.
https://www.dropbox.com/s/0afepjqkth9vujt/Max%20Distance%20WSPRnet%20Links.png?dl=0
@All,
Interesting Propagation Case from the current Case Study.
An interesting propagation case is from transmitter (Tx) call sign OZ7IT at locator JO65df on the Baltic Sea coast of Denmark, which was 481.3 km from the aircraft position at 17:26:22 UTC on an initial bearing azimuth of 61.4938°T.
At 17:38:00 UTC receiver (Rx) call sign VK4CT at locator QG62jv at Rocksberg, Queensland, Australia receives a WSPRnet protocol from OZ7IT with a SNR of -18 dB.
The great circle path from OZ7IT to VK4CT is on an initial bearing azimuth of 61.4938°T, so the aircraft crossed the great circle path between Tx and Rx.
The received SNR of -18 dB is an anomaly at 0.95 SD when compared to the 4 WSPRnet links received on the 4th September 2022.
I discount this link over the timeframe ±3 hours because the count was only 3.
I looked at ±1 day ±3 hours and the count was 25, but -18 dB was no longer regarded as an anomaly at 0.58 SD.
I then noticed at 17:28:00 UTC VK4CT receives a WSPRnet protocol from OZ2BR at locator JO65di with a SNR of -14 dB, which is an anomaly of 1.21 SD over a ±3 hours timeframe.
I discounted this link it passes 2.5 nmi from the aircraft and is outside my 2.0 nmi circle of uncertainty.
@Richard
Excellent work by you, Dr. Hannes Coetzee, and Prof. Maskell, and courageous reporting by Geoffrey Thomas. The WSPR crash site fits within the UWA drift analysis recommended search area. Brace for incoming from the detractors, but we will not duck and cover, and never run!
Search On !
@All,
Two comments on the recent case study by Prof. Simon Maskell:
“The analysis involves a Cessna over Europe, rather than a 777 over the Indian Ocean, and, while promising, as a result of the relatively small dataset considered, is not definitive.
However, it is also clear to me that the analysis implies it is probable WSPR can detect the Cessna better than can be explained by chance.
It is therefore likely that an algorithm could exist that can track the aircraft’s location by processing the detections derived from the raw WSPR data.”
… and …
“I think what you have said in the report is logical and statistically correct. My advice is that you should take these results to Ocean Infinity.”
We sent our case study to Ocean Infinity yesterday for their review.
@All,
Victor Iannello, Mick Gilbert and Steve Kent all claim to have read our latest case study but somehow miss one of the most important points.
“The plot of the True Positive Rate against the False Positive Rate for the Receiver Operating Characteristic (ROC) curve during the cruise phase of the flight shows an improved level of aircraft detection. The ROC curve is based on the 70 observations during the cruise and the area under the curve increases from 58.66% to 60.43%.” – Discussion of the Results – Section 7.2 – (please see Figure 52).
Victor Iannello concludes:
“So by my count, with a threshold of 0.75, after including the discarded data, the True Positive rate remains at 52% and the False Positive rate increases from 37% to 44%, versus a rate of 45% of detections due to chance (assuming that SNRs are normally distributed).”
“The utility of the GDTAAA plane detector just went from weak to almost imperceptible, just as physics would predict. The prospect of using this detector to reconstruct the path of MH370 is once again proven to be junk science.”
Mick Gilbert concludes:
“Victor, doubtless Professor Maskell is familiar with the traditional academic point system for classifying the utility of a methodology based on its area under the ROC curve results;
.90-1.0 = excellent (A)
.80-.90 = good (B)
.70-.80 = fair (C)
.60-.70 = poor (D)
.50-.60 = fail (F)
With an overall AUROC of 58.66% the authors get an F.”
“We might well ask whether anyone in any position of authority on either side of the negotiations to fund a renewed search would treat a methodology with essentially no predictive capability seriously. Who could possible say that a methodology with such manifestly poor results clears the “credible” part of the 2017 “credible new information” test?”
Steve Kent concludes:
“Godfrey takes the unjustified step of discarding duplicates, retaining only the links that cross the true aircraft position. Since the majority of the discarded links are positive detections (21 out of 28), this means that the retained links are mainly true positives while the discarded links would have been false positives had they been kept. This process introduces a bias such that the WSPR hypothesis will always be favoured, even if the null hypothesis were true. A better designed test would have avoided this issue altogether”.
“This analysis ignores the fact that rays do not follow precise great circles (as assumed by Godfrey) due to the spheroidal shape of the earth, introducing cross-track offsets of order 10-15 nm and thus making the entire exercise total nonsense.”
In response we would like to point out the following:
1. Independent Review.
Prof. Simon Maskell is on the record as stating: “the report is logical and statistically correct.”
2. Discarding Duplicates.
The results in the cruise even with the duplicates is the same at 58%.
https://www.dropbox.com/s/wdql880ybvccuz9/ROC%2073%20Cruise%20Observations%20with%20optimal%20operating%20point%20and%20confidence%20intervals.png?dl=0
The duplicates arise mostly from the spiral dive, where the aircraft in the last 4 minutes of flight is all within a circle with a radius of 2 nmi, and also in part from the alignment of the aircraft track with the WSPRnet link azimuth.
3. Methodology Classification.
Gilbert invents a new 5 point Likert rating scale. He probably meant “Excellent, Very Good, Good, Fair, Poor”. There is no “F” for “Fail” in a Likert scale. We also note the next letter in the alphabet after “D” is in fact “E” and not “F”. Neither Prof. Maskell, nor we, have heard of this Gilbert rating scale.
In fact a result of 60.43% is “Fair” and not “Fail”.
4. Poorly Designed Test.
The tragic flight of a Cessna 551 Citation II/SP registration OE-FGR, was not a poorly designed test.
In fact the aircraft that crashed after fuel exhaustion into the Baltic Sea off the coast of Latvia on Sunday 4th September 2022 was not a test at all.
Like MH370 it was an incident that should not have happened and any investigation into the incident has the prime goal to prevent such an incident ever happening again.
5. Cross-Track Errors.
Steve Kent states: “I computed the rms cross-track error for each of the 183 links in the data table. The median rms is about 2.1 nm, which is the maximum cross-track error allowed by Godfrey”
Steve Kent omits to state that the average number of SNR anomalous WSPRnet links at each point in the cruise of the aircraft is 4.3 and not a single link as he implies. When three or more anomalous links intersect at the aircraft position, as is the case at each point in the time frame analysed, then the cross-track error is minimal.
It seems that there was some reference to the younger pilot reacting to something aboard this MH370 plane after take-off . That he left the cockpit to use his cell phone , something like that . Has anyone guessed at how the older pilot disabled the younger pilot and how much into the flight ? How would he have been disabled , possibly shot with a gun ???
@Barbara Roth,
Welcome to the blog!
There is no evidence that the co-pilot reacted to something on board MH370 after take off that I am aware of.
There is evidence that his mobile phone was switched on and detected by a mobile phone provider at a tower on the island of Penang.
It is possible if the co-pilot leaves the cockpit to lock the cockpit door and prevent reentry.
It is difficult to take a gun onboard an aircraft due to the security screening.
Although my qualifications may not compare to those who have contributed to the search for MH370, I would like to express my observations regarding the similarities between the 1999 South Dakota Learjet crash and the MH370 case.
It is plausible that the aircraft may have flown unmanned until fuel exhaustion, which would provide answers to several questions, such as why families were able to connect to their loved ones’ phones and why the wreckage remained in one piece.
In my opinion, the pilot may have become aware of a fault in the two minutes following the last contact, significant enough to make a U-turn back to Kuala Lumpur International Airport.
If the fault pertained to the communication systems, it could explain the movements on the military radar, as the pilots were likely attempting to complete checklists and re-establish communication with air traffic control. Meanwhile, cabin decompression may have led to a fate similar to that of the 1999 Learjet crash.
Overall, I believe that the efforts of those involved in the search, particularly those who have persevered despite the passage of time, are commendable.
@Lewis Joyce,
Welcome to the blog!
Different mobile phone operators handle a call to a mobile phone that is not connected to a base station anywhere in the global network of possible providers differently. Sometimes you will get a message that your call cannot be connected, sometimes they will just provide a ringing tone to make you think that your call could be connected.
The wreckage did not remain in one piece. We have recovered 39 pieces with an average weight of 4.6 kg. The zero fuel weight of the aircraft was 174,369 kg. If the aircraft fragmented at the same rate as the debris items recovered so far, then there would be 37,906 pieces.
if the pilot became aware of a fault serious enough to cause a turn back, then he would perform an emergency landing at the nearest airport. There are 3 VHF radios, 2 HF radios and a satphone in the cockpit. It is unlikely that all communications systems had failed. In an emergency the active transponder would be set to 7777. Instead both transponders were switched to standby and the ACARS system which would give position reports every 30 minutes was switched off.
The pilot was still active long after the diversion had taken place. If the landing gear was lowered towards the end of the flight, then this would require an active pilot. The aircraft made changes of speed and altitude. Turns can be programmed into the Flight Management Computer but changes of speed and altitude cannot be pre-programmed and require an active pilot. The Learjet in 1999 flew in straight and level flight at a constant airspeed until fuel exhaustion as there was no active pilot.
What puzzles me: There must have been other radio signals of passenger’s mobile phones been caught somewhere. I’ve never seen such data.
The WSPR data is interesting, I do not understand the statistics behind the geolocation to be honest.
Vy 73, DK1CAB
@Dr. Hinner,
Welcome to the blog!
We have discussed the issue that only the mobile phones from the crew were analysed and only over Malaysia. There were many more mobile phones from passengers that could have been analysed and not only over Malaysia. I am currently looking into trying to get Indonesian mobile phone data from base stations on off shore rigs.
Here are some of the most relevant comments on the subject of mobile phone detection:
https://www.mh370search.com/2023/12/18/wspr-as-radar/comment-page-1/#comment-2356
https://www.mh370search.com/2023/12/18/wspr-as-radar/comment-page-1/#comment-2372
https://www.mh370search.com/2023/02/26/the-ongoing-search-for-mh370/comment-page-1/#comment-2164
https://www.mh370search.com/2023/02/26/the-ongoing-search-for-mh370/comment-page-1/#comment-2162
https://www.mh370search.com/2022/09/08/mh370-detection-and-tracking/comment-page-1/#comment-2150
https://www.mh370search.com/2022/03/14/mh370-wspr-technical-report/comment-page-2/#comment-2036
https://www.mh370search.com/2022/09/08/mh370-detection-and-tracking/comment-page-1/#comment-1992
Our hypothesis with the WSPR data comprises both a null hypothesis and an alternate hypothesis. In other words, we are trying to show in the alternate hypothesis that WSPRnet data can be used to detect and track an aircraft when the aircraft position is at the intersection of the great circle paths between WSPR transmitters and receivers. At the same time, we are trying to show in the null hypothesis that WSPRnet data will not detect an aircraft when the aircraft position is not at the intersection of the great circle paths between WSPR transmitters and receivers.
The null hypothesis is: WSPRnet links show statistically significant anomalies when an aircraft is not on the great circle path between the transmitter and receiver.
The alternative hypothesis is: WSPRnet links show statistically significant anomalies when an aircraft is on the great circle path between the transmitter and receiver.
The objective of the papers and case studies we have published on this website is to demonstrate a statistically significant number of examples of the alternative hypothesis and show that the alternative hypothesis is generally true, whilst at the same time demonstrate a statistically significant number of examples of the null hypothesis and show that the null hypothesis is generally false.
I think it is hard to argue that a Receiver Operating Characteristic (ROC) curve that is distant from the y=x line is measuring pure noise. We presented 7 such ROC curves in our case study titled “Flight QTR901 GDTAAA WSPRnet Analysis” published 8th June 2023.
The plot of the True Positive Rate against the False Positive Rate is a standard test in statistics and is called the ROC curve. It is a test of sensitivity and specificity. Sensitivity (true positive rate) refers to the probability of a positive test, conditioned on truly being positive. Specificity (true negative rate) refers to the probability of a negative test, conditioned on truly being negative.
We are about to publish a set of ROC curves with a larger number of observations taken from our latest paper titled “How does WSPR detect Aircraft over long Distances?” and published in the post on WSPR Aircraft Tracking.
My co-author Prof. Simon Maskell is currently working on a large scale study using around 1,000 Boeing 777 airborne during a 24 hour period, where he has the ADS-B data and WSPRnet data for all aircraft globally (not just the Boeing 777’s) at each of the 720 two minute WSPR time points.
He plans to use the results in a second study on the MH370 flight path using the processing chain for MH370 defined by the DSTG particle filter in their paper titled “Bayesian Methods in the Search for MH370” but revised to include the WSPR data.