Well, I beg to differ with the above supposition. The world is indeed a big place, and even a small amount of information can yield enormously useful constraints.
Start with the graphic below. While I make no claims for its precision, it is a useful approximation of the problem statement.
The graphic above shows the approximate maximum and minimum range associated with the fuel estimated to be on board MH370 at the time of the last radar contact West of Penang. The approximate radius of the maximum range, blue circle, is 2850 nm. The approximate radius of the minimum range, black circle, is 1100 nm. The red line is the 6th (00:11) Inmarsat arc.
The surface area between the maximum and minimum ranges is approximately 22 million square nautical miles. The distance along the 7th arc between 26S and 40S is approximately 1200 nm. If a very generous search width of 100 nm is used, the area of the 7th arc search as defined by the Inmarsat data is approximately 120000 square nm. It is clear that the Inmarsat data reduces the search possibilities by factor of almost 200, or a factor greater than two orders of magnitude. Two orders of magnitude is a huge reduction.
How can anyone possibly claim the Inmarsat is not extremely useful??
Tuesday, August 30, 2016
Sunday, August 28, 2016
Re: Iannello and Godfrey, “Possible Flight Path...”
Iannello and Godfrey
Very interesting. The narrative checks
a lot of boxes. Perhaps all of the boxes.
The points in the SIO on ZS's flight
simulator are certainly a compelling reason to believe that a flight
was simulated in that direction. Again, no hint of motive is
apparently provided by this new information. I say apparently because
it takes a little more thought, albeit speculative thought, to make
sense of it all.
Let's start with the Malay response to
the diversion in the first hour or two after the turn West near
IGARI. The response was below minimal standards. One could even
describe it as pathetic. Even the ICAO was critical of it, and that
is highly unusual for that organization(1).
Many people wondered why the response was not a “dialing until your
fingers bled” effort. A simple explanation is that the status (not
the exact location) of the aircraft was known. Third parties in KL
were attempting to negotiate concessions from the Malay leadership in
KL, with MH370 as the lever. The exact nature of those concessions
cannot be known, but there is certainly a large menu of options.
So ZS flew West from IGARI to play a
waiting game to the North and West of the Malay Peninsula – waiting
for word of success so that he could land the plane - Banda Aceh and
Car Nicobar being logical choices. That word never came, and the
“negotiation failed” response was to fly South and destroy the
aircraft in the SIO. While that action may seem extreme, it was the
only possible response. You cannot retreat from a situation like
that without carrying out the stated threat. Your chance of a
successful future negotiation is highly dependent on the other party
understanding that your ultimatums must be regarded very seriously.
So with the “negotiation failed”
result, ZS selected McMurdo Station as an AP destination, and
resigned himself to his fate. His ambition of becoming a national
hero was dashed, and he had to pay the price he knew full well was a
possible outcome of this bold plan. So why practice the route on his
simulator? Surely a pilot of his skill could execute that route
without practice. The simple and obvious answer was to indulge
curiosity. ZS wanted to know where the plane would run out of fuel,
and observe his final resting place on the planet.
The simulated route did not include the
turn near IGARI. The simulation was most likely done with the
assumption that the diversion would be performed on a route to
Europe. Scheduling and other constraints required a diversion from
the Beijing route. A European route would have been preferred, since
the diversion would not be noticed until the plane had flown well
past the Malay Peninsula.
I think the implication in the
“discussion” section of the latest IG narrative is excellent. A
logical place to look for the aircraft is where a flight path to
McMurdo crosses the Inmarsat 7th BTO arc. While the
precise location of the FMT in the actual route flown is a bit
“fuzzy”, the geometry reduces the spread in the 7th
arc crossing locations. Also the latitude of the crossing derived in
the IG narrative, ~27S, is far more consistent with the debris finds
(and lack of finds) than is ~38S.
Wednesday, August 24, 2016
More on Ping Ring Radii and Other Good Stuff
Found this data from Dr. Steel. Our values agree very closely so I'll just publish his table with attribution. Good reference, IMO, to 3F1 parameters including sat position, sat velocity, sub-satellite position on earth (Lat Lon columns), and ping ring radius (Approx Great circle distance).
Where is that Ring (18:25:27)
Wednesday, May 6, 2015
Obviously the accuracy of the handshake rings is of critical importance to the forensics related to the terminal location of MH370. My initial ring calculations (done a long time ago) were relatively "casual". The results were placed in a table which I have continued to use since. While these results have had no important bearing on modeling candidate flight paths, they would become important relative to directing search efforts or for use in comparisons with other data. One such comparison is the radar data obtained from Butterworth RMAFB. Of particular interest is the 18:25:27 ring which is very close in time to the last radar contact at 18:22. The 18:25:27 ring is quantified below.
Note: This value is correct only for analytics relatively close to the equator where the WGS84 earth radius is very close to 6378.
My ancient 18:25:27 calculation of 3630 is clearly astray by almost 100km. Not very useful for anything but flight path feasibility calculations. An earlier post made here relative to radar implications is obviously flawed, and will be revisited.
Figure 1 - GES / Satellite / Aircraft Geometry
(view is orthogonal to a plane containing R_s and (R_e +H))
Note: This value is correct only for analytics relatively close to the equator where the WGS84 earth radius is very close to 6378.
My ancient 18:25:27 calculation of 3630 is clearly astray by almost 100km. Not very useful for anything but flight path feasibility calculations. An earlier post made here relative to radar implications is obviously flawed, and will be revisited.
Friday, August 5, 2016
Tuesday, August 2, 2016
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