I was referring to CVR/FDRs in general being specialist equipment requiring specialist facilities to process. In any case, I would be very interested to find out where those from this accident are read. It appears from a post upthread there are new facilities in New Dehli that could be used. Having said that, for the EK 521 accident in Dubai the recorders were sent to the UK for analysis, despite a "flight data recorder centre" in Abu Dhabi being opened (again with much fanfare) by the UAE GCAA five years before the occurrence.
The Indian AAIB successfully downloaded both FDR and CVR data from an Air India 787's EAFR relating to an incident in 2018, so your misgivings on that account are unfounded.
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): AAIB (All)AAIB (India)CVREAFRFDR
the difference may lay in the content that was recorded and not so much the 2 identical EAFR's. Only the forward EAFR is connected to a dedicated backup battery (RIPS) which also provides backup power to the Cockpit Area Microphone. So in case of a major electrical power mishap, the forward - and likely (externally?) damaged - EAFR might be crucial for recovering all available CVRecordings. Hence the somewhat understandable split-up in news-reports, between FDR data (from the rear EAFR) and complete CVR recordings (from the forward).
Absolutely.
If the aft EAFR ceased recording at the point (just short of the runway end) where the ADS-B and likely everything else went dark, then the extra 30 seconds of CVR recording from the forward recorder could well be crucial to the investigation.
Could the fellow who was cited as having heard the CVR and commended the pilot's actions.... because he trained under the Captain, and would be familiar with his speech, have been bought in to
validate
who was speaking on the transcript?
That's an interesting possibility. The independent power supply for the forward recorder also powers the cockpit area microphone, but not the individual crew mikes, so working out who said what could well be dependent on being able to recognise the voices.
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): CVRCockpit Area Audio
Do both EAFRs run on emergency power? Could it be possible that only ONE (if any) EAFR unit was recording after the supposed loss of thrust on both engines? If the other one is severely damaged we might as well end up with NO EAFR data from the critical last part of the flight. Perhaps both units are severely damaged? I\x92m not convinced your optimism is entirely warranted.
No, only the forward EAFR is connected to an independent power supply, and of course it will then only collect data from sources that themselves remain powered on.
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): EAFR
The figures being bandied around for the speed profile during the airborne segment of the TOD look a bit odd.
Firstly, because there isn't actually any speed data in the FlightRadar24 download (and even if there were, the aircraft doesn't send Airborne Velocity packets at the same time as Airborne Position ones). This is a longstanding issue with FR24, and it means that any graphic showing speed at a given position isn't necessarily 100% accurate:
Secondly, and assuming that FR24 has calculated GS as a second-order parameter, rather than a transmitted value, the instantaneous values still don't quite match the data in the download.
It's easy to see that by correlating how far the aircraft has progressed against the data timestamps. Charting the remaining distance to the end of the runway against an arbitrary timescale starting from the first of the 8 data points looks like this:
Obviously the slope/gradient of the blue line represents the average GS between successive points. The yellow reference line corresponds to a GS of 180 kts (ignore the offset, just use the slope for comparison).
Yes, the aircraft had clearly slowed down after rotation, but the final two data points appear to show that it had stopped decelerating by the time the transponder stopped sending.
One wonders how FR24 arrived at its groundspeed values?
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): FlightRadar24
And FR24. It's a commercial website for aircraft spotters. It is not an accurate source of information for professional flyers. If I see a poster linking to it I ignore them as well.
FR24 has, at the last count, 3 fundamental issues with the way it reports and displays data.
All are readily worked around, after which what's left is the same data that underpins many of today's ATC systems.
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): FlightRadar24
I have no idea if he actually knew how much fuel was on board, or whether he'd simply been told it was "full" and somebody had looked up the capacity (126k litres) and he then quoted that "full" number. Or whether, in fact, there was an excess of fuel. But since that seems so far the only public statement on fuel load, it shouldn't just be dismissed out of hand.
If only there were an easy way of telling how much fuel had been loaded for the sector ...
With 'intact' being the crucial part of these recent posts. It is my understanding that a suitably equipped LAME can simply download the FDR data from an installed EAFR (CVR requires dismounting). So downloading as such, isn't the issue.
You may be thinking of a Quick Access Recorder (QAR), which is indeed designed to be downloaded in situ. They've been around for a while.
That aside, I think we're agreed that downloading an intact FDR/EAFR is probably several orders of magnitude easier than one that's been burnt, battered or bruised.
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): CVREAFRFDR
I don't believe it's absolutely confirmed yet but earlier posts (thank you
V1... Ooops
et al
) indicated that the unit in question may be a GE Aviation Model 3254F,
the document here
gives some good detail, along with
another
doc from Skybrary that has some relevant information..
Yes, the AIC 787 had the GE EAFR..
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): EAFRV1
The requirements I have seen indicate that RIPS is applicable only to CVR or the CVR function of an EAFD. If you are aware of any requirement for RIPS to support flight data recording would you please provide a reference.
I believe the GE EAFR continues to function as both FDR and CVR for a minimum of 10 minutes following a power failure.
However you are correct in that the requirements only specify that the CVR functions and the CAM must continue to operate.
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): CVREAFRFDRRIPS
I think there is mileage in Richard Godfrey's reasoning, and worth listening to. Here is the latest "Airline News by Geoffrey Thomas" from 6 hours ago.
An "expert" who can't get something as basic as a runway slope calculation anything close to correct doesn't inspire much confidence in his other "analysis".
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): Self Proclaimed Experts
I believe the *inspection* was not conducted, and whether there was a fault with the configuration of the switch on the accident aircraft is not answered in the report.
The report explicitly states:
"As per the information from Air India, the suggested inspections were not carried out"
I think the question is *how* fuel switches were accidentally turned off by flight crew, given what\x92s said about their protections?
BBC Radio 5 this morning included an interview with a former 747 pilot describing an engine rundown on taxi out at BKK, caused by the switch issue described in the SB (he had been unaware of the SB up to that point).
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): BBCFuel (All)Fuel Cutoff Switches
It is with great sadness that I woke this morning having accepted the fact that the uncontrolled engine fire is no longer in the number one position of worst pilots nightmare.
FARs require that the CVR be "operated continuously from the start of the use of the checklist (before starting engines for the purpose of flight), to completion of the final checklist at the termination of the flight".
Subjects
(links are to this post in the relevant subject page so that this post can be seen in context): CVR
