[Peetwo]

..But as recently as Friday ATSB commissioner Greg Hood reiterated the view of the search team that satellite data from the Boeing 777 jet suggested it was plunging at almost 400km/h just before it crashed into the sea with 239 passengers and crew...

And quote from Greg Hood West Oz/Airline Rating/Yahoo7 article last Friday:

..Australia’s crash investigator has revealed that data indicates MH370 could have been plunging at almost 400km/h just before it smashed into the sea with 239 passengers and crew.


In his first interview as chief commissioner of the Australian Transport Safety Bureau, Greg Hood told The West Australian the automated satellite link with the Boeing 777 showed its descent increased dramatically from about 1200m a minute to up to 6700m a minute... 

In last night 60 Minutes program Peter Foley rehashed some of the same information about the aircraft rate of descent at the presumed end of flight after the final 00:19 aircraft to satellite (BFO) ping. Refer to Part I YouTube video at about 08:50 minutes.

After reviewing all the available DSTG/ATSB information off the ATSB MH370 reports page - see HERE - nowhere is it stated that ROD and/or airspeed (stated as 400km/h) was calculated off the aircraft transmitted satellite data. Which means this is either new information or information that the ATSB, SSWG and the Annex 13 JIT investigators have previously not made public.  

It could be that the ETM (engine trend monitoring) system data that was routinely transmitted from the a/c was somehow corrupted or was abbreviated but the following article gives you an idea of the sort of information that should have been transmitted from the aircraft and then recorded at the RR ground station:  

Aircraft Engine Monitoring: How It Works And How It Could Help Malaysia Air 370 Crash Investigators

P2 comment: Ironically this article was written some days before the Inmarsat BFO recorded data was first made public, with that in mind it is very interesting to read some of the insightful comments.

The following pic is taken from the Rolls Royce basic blurb on their Engine Health Management system - see HERE - showing the engine probes and the data they record, in particular refer to the aircraft data box:

Update to above post :  Geoffrey Thomas & Steve Creedy have apparently joined forces again to do a follow up to the MH370 Hoody article, this time they interview Blaine Gibson to give his perspective on the 60 Minutes program and the resulting MSM & Social media coverage since:  

MH370 sleuth says media reports are wrong on debris
Geoffrey Thomas & Steve Creedy 02 Aug 2016

US lawyer who has found most of the debris from MH370 says the 60 Minutes program's expert is not correctMr Blaine with the pieces of debris he found in Madagascar In March this year Jean Dominique and Suzy Vitry found this piece from the cabin interior on the beach of La Reunion. Confirmed as highly likely to be from MH370 by the ATSB 

http://www.airlineratings.com/news/749/m...tDZbL.dpuf

However what perked my interest was the following quoted text, which once again confirms the recent ATSB (Hood & Foley) analysis of satellite data pointing towards calculated ROD & TAS/Mach No. ("400km/h") at the assumed end of flight (00:19 BFO) :

The ATSB is sticking with the current search area based on satellite data and say the uncontrolled ditching is still the hypothesis that bests fits the few available facts .


These include an analysis of frequency differences that indicated the aircraft was descending between 1800m per minute and 3000m per minute during its final log-on request to a geostationary satellite over the Indian Ocean and at up to 6700m per minute eight seconds later when it receives an acknowledgment from ground station in Perth.

Another piece of key evidence is sitting in the ATSB laboratories in Canberra. Failure analysts are looking a large piece of the aircraft’s right main wing flap to see if it was extended on impact. 

If this proves not to be the case, it will serious blow to the controlled landing theory. 

So in case I missed something I revisited the DSTG analysis report - Bayesian Methods in the Search for MH370.

Reference extracts:

10.5 End of Flight

The output of the particle filter is an estimate of the pdf of the aircraft state at 00:19.

The aircraft was still in the air at this time and a model is required to describe the

distribution of how it may have descended. This has been primarily the responsibility

of the ATSB and the other members of the search team. A discussion of the different

methods used to model the potential motion is presented in [5]. The model for aircraft

motion after 00:19 leads to a prioritisation of the search along and around the final

BTO arc...

...The analysis in [5] leads to a probable scenario where the aircraft ran out of fuel at

some time between 00:11 and 00:19. The final satellite communications message

could be due to the modem rebooting under auxiliary power. Under this hypothesis,

the aircraft was already unpowered at 00:19. The spread of the kernel function is
then determined by the distance over which the aircraft could have moved, which

depends on whether or not the aircraft was under human control during this period.

Flight simulator studies of uncontrolled descents have shown a high likelihood

of the aircraft reaching zero altitude within 15 nm of the beginning of descent [5].


However, the beginning of descent is not known. It is possible for the aircraft to have

travelled farther, especially if a human was controlling the aircraft. As an indicative

kernel, and following advice from the ATSB, a uniform disc of radius 15 nm with

a Gaussian drop off with standard deviation 30 nm beyond this was chosen; this

represents the accident investigators’ assessment of the likely scenarios...

---

& from Para 10.9:

...The factors that do make a significant difference to the output pdf are the assumed

spread of Mach number and the end of flight model. The assumed Mach number

range covers the speeds feasible over long time durations. The lower end of this

speed range results in the Northern part of the pdf and the higher end of the speed

range results in the Southern part. Restricting the speed to only Mach numbers above

0.8, for example, would contract the pdf to the South. The consequence is that using

a smaller speed range within the bounds already modelled leads to a subset of the

search zone. If a different end of flight model is assumed the general consequence

is to spread the search zone over a larger area. Simulations have predicted that

the maximum distance that the aircraft could have glided under human control is

approximately 100 nm after 00:19 [5]. The search zone that this scenario would

imply is very much larger...

As can be seen there is no reference, from DSTG at least, to any of the BFO data (after 00:19) being calculated as stated in the airlineratings.com article; or indeed the 60 Minutes Peter Foley quote (Part I 08:50).

Within the DSTG book there is several references to the 00:19 BFO data being "unreliable". However apparently the ATSB, unlike the DSTG, are not concerned about this potentially "unreliable" data when analysing...

"...frequency differences that indicated the aircraft was descending between 1800m per minute and 3000m per minute ...and at up to 6700m per minute eight seconds later..."  

This raises a number of questions on the veracity of the statements made by CC Hood & Peter Foley.

Q/ After all this time what leads the ATSB to now believe the integrity of the 00:19 BFO as being secure enough to trust to calculate end of flight rates of descent between 1800 to 6700 metres per minute?

Q/ Where did the airspeed reference (i.e. 400 km/hour) come from?   

Q/ Finally how come we are only finding out about this 'analysis' now? 


So Hoody et.al in the words of former HoR MP and now Senator elect Pauline Hanson..."Please explain??" 



MTF...P2