Category Archives: MH370

Articles about satellites and their limitations for the missing Malaysian airliner, MH370.

Satellite Limitations Searching for MH370

Image hosted on OgleEarth.com.

It’s been awhile since there’s been anything said about the mission Malaysian MH370 passenger jet,  That’s good, because maybe it allows investigators to investigate.  It’s potentially bad if the entire investigation has been dropped (doesn’t appear to be the case though–read about that, here).

Some image swaths of the area. Image hosted on OgleEarth.com.

It appears that Space Safety Magazine has remembered the missing airliner and decided to re-explain, in an article published yesterday, why satellites really aren’t the solution to finding the airliner.  The article brings up the problem that such a big area, in which the airliner disappeared, represents a problem for satellites.  There are trade-offs of satellite imagery/remote sensing payloads covering a large area with relatively low resolution, or covering a small area with great fidelity.  For an explanation about why there’s trade-offs, please go to one of my lessons about them, here.

What I didn’t know is that China activated the UN Disaster Charter to help with searching for MH370.  The Charter is primarily meant to allocate satellites from different countries and companies to help countries facing major disasters, like earthquakes, typhoons, and flooding.  It’s unusual, and perhaps inappropriate, to activate it for a missing airliner.  It might have been a knee-jerk response by China to it’s citizens, perhaps to appear like it’s “doing something” to help find MH370.  If you would like to learn a little bit more about the Disaster Charter, you can read about it, here.

But if all of what Space Safety Magazine has posted sounds a little familiar, it may have been because you’ve already read a bit more in-depth about why satellites are limited in their search for MH370 in my March 16 post for Clearancejobs.com.  There’s also a bit more about the issues with InMarSat’s analysis of their data from The Atlantic, here.  If you haven’t read either one, I recommend reading them.

The Space Safety Magazine post also notes that information regarding military satellite observations–or the lack of information about them–certainly hasn’t been forthcoming or supporting the search very well.  I did note that Space Based InfraRed System (SBIRS)/Defense Support Program (DSP) satellites were reported as not seeing any explosion in the area being searched.  But not much else has come to the fore from “national technical means”–from any country.

But after all the exposition, the post comes to the same conclusion I gave about the question of whether satellites will be able to detect and pinpoint wayward airliners: it is still a wishy-washy “It depends.”

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Space, Transparency, and MH370

Malaysian Mystery

The Atlantic’s Ari Schulman has a terrific explanation regarding Inmarsat’s analysis of the “pings” their geostationary satellite received from Malaysian Airlines flight 370.  Of more interest, the article also talks about why Inmarsat’s analysis may be incorrect.  There are some puzzling problems with the data Inmarsat produced.  The “ping” doppler values appear to be positive, when they should be negative.  The aircraft itself was said to be moving, when in fact it was still sitting at the airport, which means the “ping” values should have been near zero.

The upshot of all this is that a lot of people, including the Malaysian government, relied on Inmarsat’s analysis to figure out where exactly to look for the missing airliner.  But if Inmarsat’s analysis is incorrect, as the article is arguing, then perhaps everyone is looking in the wrong ocean.

According to the post, Inmarsat is fairly confident in their analysis of the airliner’s “pings.”  But the inconsistencies in their data imply to other analysts (who aren’t working for Inmarsat) that there’s no reason for that confidence.

I am unsure why Inmarsat doesn’t bother to clarify what they’ve done, going step by step.  Perhaps it’s because such an explanation might shed light on a capability which they are trying to keep secret?  There should be some kind of transparency that allows for the vetting of their analysis methods and data production.  Hopefully Inmarsat will come forth and present how they did what they did.

If you are curious about Inmarsat’s analysis, as well as The Atlantic’s, then please read the article.

Why Space Matters: Malaysian Malaise Mit Man-Made Moons

The Epoch Times posted this article explaining a bit more about the limitations of satellites in finding Malaysian Airlines MH370.  This finding in spite of DigitalGlobe’s initiative with Tomnod to get many eyes looking for something unusual in the search areas.

In previous posts, I’ve talked about the odds and limitations of Low Earth Orbit (LEO) and Geosynchronous (GEO) imagery satellites viewing the actual flight of the airplane in their Field of View.  But now there are satellites looking for the sad traces of the airplane.  This time, at least according to the Epoch Times post, the limitations are training and imagery resolution.  The training is in regard to imagery analysts, who can find differences in pictures that perhaps Tomnod volunteers miss.  Imagery analysts have the training and experience to do that.

The resolution issue comes from the fact that most commercial imagery satellites are allowed to release imagery in resolutions of a half a meter or more, even if the satellites’ payloads are more capable (like DigitalGlobe 3, with a 31 centimeter resolution).  So even with all those eager Tomnod volunteers, the search for MH370 debris is being hobbled through federal government regulations that won’t allow them to see the “good stuff.”  Using higher resolution imagery is no guarantee for finding the airplane’s pieces, but it couldn’t hurt.  Of course, maybe it’s moot, and there’s just not much to find.

Can Satellites Help Find Lost Aircraft? Can You? Maybe!

Malaysian Mystery

“The mystery surrounding the unfortunate Malaysian Flight MH370 has caused some of the more astute reporters to ask questions about satellites.  Specifically, were there any satellites over the area the airplane disappeared in?  And if there were, would they, or could they have picked up anything to help find the missing airplane?  Ultimately, can satellites help find lost aircraft?”

See if my answers and guesses are interesting to you in the rest of my Clearancejobs.com article, in:  “How Satellites Could Find Malaysian Flight MH370.”

This is Why Space Matters: Aircraft Tracking

GPS Satellites

According to this GPS World post, Harris Corporation intends to make it easier to track aircraft around the world.  How?  Simple–by using GPS and Iridium NEXT satellites.  “Wait,” you might interject, “Don’t airplanes already use GPS?”  Well, yes they do, but this is why Iridium NEXT is important, too.

The point of GPS has almost always been for the receiver to know exactly where it is on the Earth’s surface.  So anyone who has a GPS receiver, and is in a location where they can receive a few GPS satellite signals, knows exactly what their coordinates are.  But GPS satellites were never really intended to receive signals back from receivers and then transfer it to the satellite ground station.  So for a while now, airplanes have been using ground-based communications networks to relay their GPS location.  But this depends on line of sight and the availability of land.

If there’s no land, there’s no way for an airplane, once it gets past a certain point, to be tracked through the ground communications network.  This is where Harris Corp. and partner Aireon, are stepping in with Iridium NEXT.  With 66 Low Earth Orbiting (LEO) Iridium satellites, pretty much the whole of Earth’s surface will be in view.  So a new kind of transmitter on the aircraft will shoot up to a new GPS signal receiver payload which will be in addition to the Iridium satellite’s regular payload.  The receiver relays the signal until it gets back to whichever aircraft control center needing information about where the aircraft is.  Pretty cool, eh?

In the post, Iridium satellites with the new GPS receiver payload won’t be launched until sometime in 2015.  If something like this were in play now, perhaps it would’ve helped with finding the Malaysian flight.