Diversion 1
At this point, just past waypoint IGARI, the nearest diversion airport  with an adequate runway, was at Kota Bharu (WMKC), at a distance of 89.6 NM (11.2 minutes flying time) on a bearing of 241.5°T.

MH370 initiated a turn back at 17:21:53 UTC toward WMKC.

MH370 passed close to WMKC at 17:36:33 UTC, but it was decided not to attempt a landing.

WMKC only operates from 06:00 to 23:30 local time and therefore had been closed for 2 hours.

A Boeing 777-200ER with Trent engines has a maximum landing weight of 213,180 kg. The weight of MH370 at 17:36:33 UTC is estimated at 214,736 kg. This is over the maximum landing weight, but that would not have prevented an attempted landing in an extreme situation. 


Diversion 2 
At WMKC, the nearest next diversion airport was at Penang (WMKP), at a distance of 137 NM (15.5 minutes flying time) on a bearing of 242.8°T.

MH370 passed close to WMKP at 17:51:43 UTC, but it was also decided not to attempt a landing.

WMKP operates 24 hours but with restrictions. There are currently no scheduled arrivals or departures between 00:40 and 06:25 local time. MH370 passed by at around 01:51 local time.

The weight of MH370 at WMKP is estimated at 213,085 kg and marginally within the allowed maximum landing weight.


Diversion 3 
At WMKP, the nearest diversion airport was at Langkawi (WMKL), at a distance of 72.4 NM (8.3 minutes flying time) on a bearing of 330.7°T.

WMKL only operates from 07:00 to 23:00 local time. A diversion to WMKL was not attempted.

MH370 proceeded across the Malacca Straits toward waypoint VAMPI, where fuel could be dumped or at least used up (if the fuel dumping pump had failed). This would reduce the risk incurred in any emergency landing. 


Diversion 4 
At waypoint VAMPI in the Malacca Strait, the nearest diversion airport was at Phuket (VTSP), at a distance of 126.1 NM (14.7 minutes flying time) on a bearing of 20.3°T.

VTSP operates 24 hours and is quite a busy airport serving the tourist area in Southern Thailand. A diversion to VTSP was not attempted.

MH370 proceeded on Flight Route N571 up the Malacca Strait.


Diversion 5 
At waypoint NILAM, the nearest diversion airport was at Banda Aceh (WITT), at a distance of 82.6 NM (10.1 minutes flying time) on a bearing of 205.1°T.

WITT only operates from 07:00 to 18:00 local time. A diversion to WITT was not attempted.

MH370 proceeded on Flight Route N571 toward the Andaman Islands.


Diversion 6 
At waypoint IGOGU, the nearest diversion airport was at Car Nicobar (VOCX), at a distance of 118.4 NM (14.4 minutes flying time) on a bearing of 307.1°T.

VOCX is operated by the Indian Air Force and is seldom used for commercial traffic. It does not operate 24 hours. They even let cattle stray onto the runway and there is a cautionary note in the pilot’s guide for VOCX to this effect. A landing at VOCX was not attempted.


Diversion 7 
At this point you run out of diversion airports that are close by.

The next diversion airport would be Colombo Airport (VCBI) but that is 777 NM and 1.5 hours away.

Colombo Airport operates 24 hours and is quite busy, but if you have a problem with the transponders, VHF radios and possibly even the aircraft lights (navigation and landing lights might have failed due to an electrical problem), you would prefer a quiet airport.

It is easier to land in the daylight than at night (especially without functioning landing lights), so going further west is not the answer to being able to land in daylight, you should rather head east and south.

Sunrise on 8th March 2014 was at 07:22 local time in Kuala Lumpur, but at 05:06 local time in the Cocos Islands.

Cocos Island Airport (YPCC) has an adequate runway and is a quiet airport with little traffic, and MH370 could make it there just before sunrise. 

Hypothesis: MH370 turned south east on a bearing of 169.4°T for Cocos Island Airport.

Obviously, MH370 did not land at Cocos Island Airport either and appears to head at first for Learmonth (at the NW tip of Australia) and later for Perth instead (neither of were reachable with the remaining fuel). 


Airport Surface Winds 
In all cases, the surface winds at each possible diversion airport were light and would not have prevented an attempted landing (see table below).


BTO and BFO data 
The BTO and BFO data show essentially a perfect fit for a flight path from VOCX to YPCC as above.

At each point the BTO error and the BFO error is zero (although I still believe the approach used in the McMurdo paper is better, where BTO and BFO errors are constrained only to certain limits).

In contrast to the McMurdo flight route, this option allows changes after VOCX in both heading and Mach speed. 

The McMurdo flight route, with a constant Great Circle path and constant Mach, does not require an active pilot after VOCX, whereas this hypothesis requires an active pilot until the end.


Kate Tee 
The flight path from VOCX to YPCC passes close to the possible sighting made by Kate Tee.

If there was no loiter at VOCX, the timing of the Kate Tee sighting also fits.

I estimate MH370 was at VOCX at 19:02:33 UTC and would take 22 minutes 36 seconds to reach the area around the Kate Tee sighting at 6.63N 94.44E.

This would give an arrival time in the area where Kate Tee made her sighting at about 19:25:09 UTC.

From the GPS log of Kate Tee’s boat, the time of the MH370 sighting was placed at around 19:25:20 UTC.


Drift Analysis 
The MH370 end point following the flight path from VOCX, past YPCC until fuel exhaustion is located near 23°S 102°E.

Although there have been several drift analyses reported with a range of results, their common factor is that the floating debris started from a point much further north than the current search area.


Table, Map and Flight Route 
The table below indicates the relevant data, the key points mentioned and the subsequent flight route. The map following it indicates the locations of the points mentioned above. After that is a map showing the flight route southwards that results from the modelling described above. 

It is evident that the buoy 101703 spent a lot of time around the 7th Arc from 8th March 2014 onwards. Other buoys made a more direct route across the Indian Ocean.

In fact it was not until 22nd November 2014 that this buoy left the area of the 7th Arc to begin its journey to the Cargadas Carajas Shoals.

If MH370 ended at 23.5°S on the 7th Arc, then it is possible that floating debris stayed in that area for several months.


Global Drifter Program Buoy 101703 from the 7th Arc 
When the buoy finally started its journey from the 7th Arc, it took 8 months to reach its destination 3,390 NM away, at an average speed of 0.579 knots and a maximum speed of 1.55 knots near the end (see map below).

The buoy kept its drogue for the whole journey and therefore provides reliable drift data.


Goose Barnacles 
The flaperon found in Réunion carried a significant population of goose barnacles. 

The average sea temperature for the journey of the buoy 101703 across the Indian Ocean was 27.359°C. 

Goose barnacles (Lepas anatifera) are most abundant in tropical and subtropical waters where sea temperatures exceed 18-20 ºC. (Castro, et al., 1999; Nobanis, 2008; Patel, 1959). 

Approximately 120 days after settlement these barnacles develop reproductive organs at temperatures between 10.2 to 18.4 ºC, but the reproductive development takes 30 days, if the surface temperature of the water is around 25 ºC. (Anderson, 1994; Cowles, 2005; “Goose barnacle (Lepas anatifera)”, 2010).

The warmer waters in the journey from 23.5°S would favour the colonisation and reproduction of goose barnacles, therefore indicating a likelihood of the flaperon spending more time at such latitudes. 


Global Drifter Program Buoy 101665 
As mentioned above, other buoys in the area of the 7th Arc on 8th March 2014 show a similar pattern.

For example, Buoy 101655 was launched in the Indian Ocean on 13th July 2013 at 27.360°S 104.753°E off the coast of Australia (marked with a green dot on the map below).

This buoy passed near the 7th Arc at 21.716°S 102.608°E on 8th March 2014 (marked with a large white dot on the map above).

The buoy ended, after a 4.6 month journey from the 7th Arc, on 26th July 2014 at 10.023°S 63.187°E in the Mascarene Plateau between Mauritius and the Seychelles (marked with a large red dot on the map above).

Why the 60 Minutes TV programme was wrong

Michael Exner
August 11, 2016

The 60 Minutes episode concerning the loss of MH370 as broadcast recently on Channel 9 in Australia contained numerous errors. In particular the logic behind Larry Vance’s theory (that the damage to the flaperon and flap from the aircraft demonstrates that a controlled ditch must have occurred) is fatally flawed.

Vance looked at the flaperon photographs and within seconds, according to his own words, concluded that the leading and trailing edge damage patterns could only be explained by a water landing with the flaps deployed. Vance makes no attempt to consider all the other evidence that has been assembled. He then reasons that at least one engine must have been running at touchdown in order to provide the electrical and hydraulic power which he admits would be required for the flaps to have been be deployed for that touchdown.

This leads him to the further conclusion that all the well-documented evidence showing that fuel exhaustion occurred at high altitude circa 00:17:30 (UTC) must be wrong. In essence, Vance argues that his visual inspection of a few flaperon photos is all he needs to impeach the extensive body of evidence and analysis supporting the belief that fuel exhaustion occurred at about 00:17:30, followed by an APU power-up at about 00:18:30, this being followed by the AES/SDU logon at 00:19:29 and subsequent high speed crash circa 00:21 UTC.

Vance obviously has no understanding of satellite communications systems and the burst frequency offset (BFO) data analysis. He has not even tried to learn what those data can tell us from the SATCOM experts who have studied the information in considerable detail. He simply dismisses everything he does not have the background and experience to understand, and jumps to an alternative conclusion. This is very unprofessional.

The ATSB, Inmarsat, and Boeing have acknowledged from the beginning that the 00:19:29 BFO value indicates a descent rate of about 5,000 ft/min, and in recent interviews and statements, the ATSB has finally gone further and definitively stated that the 00:19:37 BFO value indicates the plane was descending at that time at a speed of 12,000 to 20,000 ft/min, exactly what the Independent Group has consistently argued for the last two years and more.

If one puts all the available evidence on the table, instead of only a few flaperon photos, a very different interpretation of the flaperon damage pattern comes to light. We know with high confidence from the Inmarsat data and fuel consumption analysis that MH370 was at high altitude and flying at over 400 knots when fuel exhaustion occurred circa 00:17:30. The flaps could not have been extended at 400 knots before fuel exhaustion, and following fuel exhaustion, they could not have been extended at any altitude or airspeed. These are facts that Vance ignores. Thus, the trailing edge damage to the flaperon could not possibly have been caused by a flaps-down water landing.

After the final ping at 00:19:37, the fact that there was no signal indicating an IFE logon at  about 00:21:07 is consistent with impact at very high speed sometime between those two times. The debris found recently by Blaine Gibson and several other private citizens is clearly consistent with the above information that indicates a high speed impact.

Given the information cited above, it is much more likely that the flaperon separated in-flight circa 00:20 due to aeroelastic flutter as the aircraft was rapidly descending. The part-flap discovered in Tanzania may also have separated prior to impact due to such flutter. These large pieces of debris were apparently not attached to the plane at the time of the main impact because in that circumstance they would have suffered far more extensive damage. Indeed, from the evidence of the much smaller pieces of debris so far recovered from both the interior and exterior of the plane, it is difficult to imagine how the flaperon and flap segment could have survived the main impact without completely disintegrating (i.e. being shattered into rather smaller pieces).

The evidence that Vance ignores, when combined with the flaperon photos, demonstrate that his statement that the aircraft undoubtedly came down in a controlled ditch is simply wrong. Vance’s statements on 60 Minutes have caused great harm to the search for the truth about what happened to MH370. His continued attempts to justify his definitive statements only exacerbate the situation.

Where is MH370 and how will it be found?

Richard Godfrey
10th July 2016

Introduction
Twenty-eight months after the disappearance of MH370, we still do not know where the aircraft crashed.

The ATSB has led an underwater search and is reaching the end of their allocated funds of $180M, used to search 120,000 square kilometres of ocean bottom.

The Government Ministers of Malaysia, China and Australia are meeting in Kuala Lumpur on 19th July 2016, and it is anticipated that they will announce the end of the underwater search for the wreckage of MH370.

Since 29th July 2015, at least fifteen internal and external aircraft parts have apparently been found, washed ashore in 11 locations on the coasts of Tanzania, Mozambique and South Africa and on the Indian Ocean islands of Rodrigues, Mauritius, Réunion and Madagascar. The majority have been confirmed as being from (or are regarded as highly likely to be from) MH370. Over 50 items of personal effects, suspected as being from the crash of MH370, have also been identified. 


Background
Investigators have collected information from many sources: primary radar detections, satellite pings, aircraft performance data, standard flight routes and waypoints, autopilot modes, autothrottle modes, fuel range, fuel endurance, weather, winds, air temperatures, magnetic variation tables, debris finds, ocean drift analyses, satellite imagery, airborne reconnaissance, hydrophone acoustics, the underwater search, etcetera. 

With all this information, why has MH370 not been found? 

The debris finds have resulted in a number of drift analyses being published, but there are large differences in the results. Critics validly point out any drift analysis is subject to many uncertainties (see this paper and also preceding papers posted on this website, and indeed elsewhere). 

There are even more satellite ping analyses that have been published, but there are also substantial differences between the results. Critics point out that although the BTO data has a ±10 km tolerance, the BFO data are proportionately worse, with a ±7 Hz tolerance. 

Inmarsat engineers, in their paper dated 4th September 2014, explained that while the BTO figures render the aircraft’s instantaneous distance from the satellite, the BFO data can be deciphered so as to get the aircraft’s speed and track relative to the satellite, subject to various assumptions. Without the BFO data, one does not know which way MH370 was heading; the BFO information indicates a path southwards across the Indian Ocean. 

The Inmarsat engineers pointed out that a ±7 Hz BFO tolerance corresponds to a +/- 9° latitude uncertainty or ±28° heading uncertainty. However, they appear to have ignored or neglected the fact that the BFO is not only related to an aircraft’s horizontal velocity but also to an aircraft’s vertical speed (or rate of climb, ROC). With three fundamental variables — ground speed, heading/track and ROC — rather than just two, fitting the BFO data to a flight path analysis is made more difficult, because you can easily adjust the ROC to fit against many different ground speeds or tracks. 

If one sets aside, for the time being, the drift analyses and the satellite BFO data, what are you left with? 

The major variable that determines the latitude of the end point is the ground speed. Not only the thrust setting and autothrottle mode are important in determining the ground speed, but also the weather data (including wind directions and speed);  the air temperature will additionally impact both air and ground speeds.

Another key variable is the assumed altitude. The air speed, air temperature, radar information, fuel range and endurance and aircraft performance data all provide constraints on the range of possible altitudes. 

A third key factor to consider is the autopilot and autothrottle mode. The air speed, radar data, fuel range and endurance, track/heading, weather data and aircraft performance data all provide clues as to the autopilot modes that were engaged. 

A fourth key factor is the time and position adopted for the final major turn (FMT): was this immediately after the last reported primary radar position at 18:22:12 UTC, or was there an extended excursion northwest, over the Andaman Islands or elsewhere? 

Finally there are uncertainties surrounding loiters, lateral path offsets, circling, aborted emergency landing(s), step climbs, and so on. Many previous posts  on this website have involved discussions of such hypothetical manoeuvres. 

In this paper I will try to determine the range of feasible MH370 end point latitudes along the 7th ping arc without using either (a) The oceanic drift modelling of floating debris; or (b) The BFO data. Herein I impose minimum and maximum speeds, altitudes, bearings, FMT position, loiters, etc., which constrain the derived end points for MH370. Obviously, if the drift analyses and the flight paths making use of the BFO data also indicate much-the-same latitude range, then a consistent picture is achieved and so one has added confidence that the derived latitude range is correct. 

In this paper, then, I ask the following question (and also try to answer it): Can one find MH370 (i.e. indicate a latitude range near the 7th arc) without having to rely on uncertain drift analyses or imprecise BFO data? 


Ground Speed versus Latitude
The Malaysian Preliminary Report (in April 2014) stated that “The tracking by the Military continued as the radar return was observed to be heading towards waypoint MEKAR, a waypoint on Airways N571 when it disappeared abruptly at 18:22:12 UTC [0222:12 MYT], 10 nautical miles (NM) after waypoint MEKAR.” 

If the aircraft turned south immediately after it disappeared from the military radar, then at an average ground speed of 300 knots the end point on the 7th Arc would be around 23°S, and at an average ground speed of 500 knots, the end point would be around 43°S (see Table 1 below). The ground speed might have been faster than 500 knots or slower than 300 knots, but these two points are 3,452 km apart and already represent an extremely large search area (if one were searching say 30 NM each side of the 7th arc). If we could put a much tighter range on the ground speed from the available information, then the search area would be much reduced. Of course, we also have to know when and where the aircraft finally turned south (the FMT); this might not have been at the earliest possible moment but could have been much later.

Table 1: Range of latitudes reached on the 7th arc for different ground speeds based on a FMT just after the final radar detection. 


Ground Speed from Radar Data
The Australian Defence Science and Technology Group (DSTG) report states that “The radar data contains regular estimates of latitude, longitude and altitude at 10 second intervals from 16:42:27 UTC to 18:01:49 UTC.” Unfortunately, this data set has not been publicly released, but the DSTG report includes a graph of ground speed derived from the primary radar data having applied a Kalman filter, which indicates a ground speed of 521 knots at 18:01:40 UTC, slowly tapering to 509 knots at 18:22:12 UTC (the final radar detection time), whilst over the Malacca Strait. 

The Malaysian Preliminary Report gives a military radar return at 17:39:59 UTC, whilst still over Malaysia, which indicates a ground speed of 529 knots at an altitude of 32,800 feet. This is not inconsistent with the DSTG graph.

Bill Holland of the Independent Group (IG) analysed the radar trace shown by the Malaysian authorities to the MH370 Next-of-Kin (NoK) in Beijing in late March 2014. This trace shows MH370 flying via waypoints VAMPI and MEKAR. From his timeline analysis, Bill found the ground speed to vary between 495 knots to 515 knots and back down to 485 knots.

Figure 1: Bill Holland’s annotated trace of primary radar positions of MH370.

In summary, we can say that the range of ground speeds of MH370 when flying above the Malacca Strait, based on radar tracking data, was between 485 and 515 knots, as indicated in Table 2 below. 

Table 2 : Ground speeds and minimum altitudes of MH370, based on primary radar information. 


Ground Speed in Mid-flight
Brian Anderson (IG) published a paper entitled “Deducing the Mid-Flight Speed of MH370”, dated 20th March 2015.  

In this paper was presented a preliminary calculation of the average ground speed of 476 knots for the mid-flight phase between 19:41:03 and 20:41:05 UTC. Brian used planar geometry at the tangent point, as MH370 passed the closest point to the satellite. 

Brian has later recalculated the average ground speed using spherical geometry, arriving at a figure of 494 knots. 

Brian needed to make certain assumptions concerning the altitude of the aircraft and the ping ring distances.

Revisiting Brian’s planar and spherical calculations, employing a range of conceivable altitudes between 25,000 feet and 45,000 feet and using the best satellite data to calculate the ping ring locations, results in a range of ground speeds between 494 knots and 502 knots. 

In summary, we can say that, subject to various necessary assumptions, the range of possible ground speeds in the mid-flight phase was from 494 knots to 502 knots.


Ground Speed between the 6th and 7th Arcs
Brian Anderson also published a paper entitled “The Last 15 Minutes of Flight of MH370”, dated 24th April 2015. This concerned the end-phase of the powered flight of MH370. 

In this paper Brian analysed the available fuel, engine and simulator information, the timings of the right engine fuel exhaustion (first), followed by the left engine fuel exhaustion (second), and the resultant air speed and ground speed profiles.

Brian’s calculation indicate that following the first engine failure there was a reduction in air speed (an ongoing deceleration) by around 19 knots per minute.

At the time of writing the above paper, Brian concluded that only with ground speeds greater than about 440 knots at 00:11 UTC (i.e. the 6th ping arc) is it possible subsequently to reach the 7th arc, even if that arc were at sea level.

Table 3: Summary of evaluations of possible ground speeds, and information sources.