Can MH370 be Located By WSPR Analysis?

[anorlunda]

In the news, they say that a new search for the missing MH370 airplane will begin at the location identified by Richard Godfrey.

I'm not qualified to judge the validity of this report. I'm asking others to weigh in with their judgements. I know we have several radio HAMs in PF membership.

If this works, it could save untold billions of dollars in the future by reducing the extent of searches for downed airplanes. If it works in real time, it might be applied in rescue, and for military purposes (Ukraine comes to mind.) It would be a development with wide and significant consequences. A global system for tracking aircraft without radar. If so, Richard Godfrey deserves honors and prizes.

The report is here: https://www.dropbox.com/s/pkolz2mxr... Analysis Technical Report 15MAR2022.pdf?dl=0

Here are a few quotes from the report:

Weak Signal Propagation Reporter (WSPR)
...
We track MH370 from the position given by the radar at 18:00 UTC and going
forward from this point we use the WSPRnet data every two minutes. ...
A novel system of detecting and tracking aircraft using radio waves is presented in this paper.
...
Amateur radio enthusiasts send thousands of test signals every two minutes around the globe. There are currently over 3 million WSPR signals recorded in the WSPRnet historic database every day sent from over 2,600 transmitters to a similar number of receivers criss-crossing the world’s land masses and oceans, but more importantly the areas out of range of traditional radar systems.
...
A new underwater search for the wreckage of MH370 is proposed and the search area is reduced from 120,000 km2 to 300 km2. The accuracy of single WSPRnet detections was found to be ± 17 km, but this can be reduced to ± 4 km with multiple intersecting WSPRnet detections.
...
We also describe how WSPR technology can be used to detect aircraft in real time.

 

[Klystron]

Apropos the historical section of the above paper,

1. Aircraft can be detected and tracked from their exhaust using a variety of methods depending on target type.
   1. Radar in the stated HF band generates partial returns from jet exhaust due to constituents in the exhaust plume, temperature difference with the surrounding atmosphere and atmospheric disturbance from the jet exhaust and aircraft body.
   2. Visible exhaust plumes can be detected using optical trackers including telescopes.
   3. Hot exhaust can be detected and tracked in the IF spectrum.
   4. Unaided human eyes can detect atmospheric contrails and follow the contrail back to the aircraft, visible by sunlight reflection or when the aircraft occludes background stars.
2. Depending on distance and bearing, several dedicated radar capabilities such as azimuth, height finding, and range determination can be combined
   1. within a single lensed antenna precluding need for bulky reflectors. A variable speed rotating feedhorn behind the lens provides the multiple signals required for tracking replacing the information feeds from dedicated remote systems, at the expense of wider area coverage.
   2. Electromechanical methods can be replaced by various synthetic and false-aperture radar imaging systems outside the scope of this historical document.

The bulk of the paper on tracking this particular Boeing 777 provides interesting techniques combining modern information processing with historical radio propagation methodology.

 

[Baluncore]

Aircraft engines tend to be leased and insured by the engine manufacturer. It is highly probable that to reduce premiums, each engine is now independently reporting GPS location along with performance data in it's routine uplinks to the manufacturer. Reliance on the timing of Inmarsat handshakes should not be needed again to locate an aircraft.

 

[anorlunda]

Aircraft engines tend to be leased and insured by the engine manufacturer. It is highly probable that to reduce premiums, each engine is now independently reporting GPS location along with performance data in it's routine uplinks to the manufacturer. Reliance on the timing of Inmarsat handshakes should not be needed again to locate an aircraft.

That may be true, but so far it didn't reveal the location of MH370. Either they didn't have the automated uplink, it or it didn't work, or it doesn't upload often enough to help.

Ditto for the Air France 447 crash in 2009. It took 2 years to locate the wreckage.

Edit: Wikipedia says this about the satellite uploads.

Satellite communication resumes​

At 02:25 MYT, the aircraft's satellite communication system sent a "log-on request" message—the first message since the ACARS transmission at 01:07—which was relayed by satellite to a ground station, both operated by satellite telecommunications company Inmarsat. After logging on to the network, the satellite data unit aboard the aircraft responded to hourly status requests from Inmarsat and two ground-to-aircraft telephone calls, at 02:39 and 07:13, which were unanswered by the cockpit.[53]: 18 [55] The final status request and aircraft acknowledgment occurred at 08:10, about 1 hour and 40 minutes after it was scheduled to arrive in Beijing. The aircraft sent a log-on request at 08:19:29, which was followed, after a response from the ground station, by a "log-on acknowledgment" message at 08:19:37. The log-on acknowledgment is the last piece of data available from Flight 370. The aircraft did not respond to a status request from Inmarsat at 09:15.

 

[Baluncore]

That may be true, but so far it didn't reveal the location of MH370. Either they didn't have the automated uplink, it or it didn't work, or it doesn't upload often enough to help.
Ditto for the Air France 447 crash in 2009. It took 2 years to locate the wreckage.

That was more than 8 years ago.
One geostationary Inmarsat over each ocean is no longer the only way to communicate. There are many new satellite systems and almost everything on the face of the Earth has a built-in GPS. That information is used by the system to synthesise the spot beam and handover smoothly to the next satellite in the constellation.

I think you will find that changes have also been made to the "engine call home" communication system that is independent of the aircraft and cannot be overridden by flipping breakers in the avionics bay.