Wiggy
 

I agree with your comments about the transponder. Not sure a radar sweeps are fast enough to catch code changes anyway.

I'm not familiar where all the components are located in that electronics bay either.

There is always the possibility that the transponder just happened to fail...I know not probable.

The "unidentified target" was tracked by the radar at RMAF Butterworth. It crossed Malay Peninsula over Thai territory, well north of the border.

MH370 went silent roughly 215 NM from Butterworth. If it turned towards Phuket, its route would have passed over the middle of Gulf of Thailand, likely never getting closer than 150 NM to the radar. If whoever was piloting it knew about the military installation, they could have stayed at 200 NM all the way. It would stay at the edge of radar range and they'd only have an intermittent track that did not extend far enough back to connect to last known position of MH370.

As far as I can tell, Thailand does not have any active air force bases on the peninsula. At best the "target" could have been tracked by a couple of civilian ATCs there. Neither does Vietnam have any bases close enough to catch the moment MH370 turned off course.

The aircraft has now been missing for six days. Assuming a mid air break up or break up on impact with water, there must have been some floating debris. It would be reasonable to expect that had this ocurred over the Malacca Narrows, bye now some floatsam would have reached the shores of these straights.
On the basis of a 5kt surface current, the floating debris would have travelled 720nm. It would be reasonable to expect that the SAR
co-ordination team would have taken this into consideration and concentrate their efforts taking into account the direction of surface water movements. However even if the point of break up is currently based on best guess, it is only a matter of time before some debris is washed up on someone`s shores. It is then that the real hard work of finding the location of the main wreckage will commence.

Didn't work so well for Helios 522...

ildarin
 

the helios crew did not recognize the BLARING HORN as cabin altitude warning, they thought it was the landing gear horn. same sound, different interval.

so they didn't put them on.

I think you badly misread your source. 8.5 _minutes_ survival time does not even pass the smell test. At -20C in room-temperature clothing and without complicating factors (e.g. wind chill or rain), survival time is going to be on the order of 12 hours.

However, if you combine -20C temperature with hypoxia, things are going to turn badly much faster.

Correction by WSJ re data link
 

Correction: Satellite, Not Engine, Data Drove Investigators’ Suspicions on Malaysia Jet Flying Time
U.S. investigators suspect that Malaysia Airlines Flight 370 stayed in the air for up to four hours past the time it reached its last confirmed location, according to two people familiar with the details, raising the possibility that the plane could have flown on for hundreds of additional miles under conditions that remain murky.

The investigators believe the plane flew for a total of up to five hours, according to these people, based on analysis of signals sent by the Boeing 777's satellite-communication link designed to automatically transmit the status of some onboard systems to the ground.

Corrections & Amplifications: An earlier version of this article incorrectly said investigators based their suspicions on signals from monitoring systems embedded in the plane’s Rolls-Royce PLC engines and described that process.

They also ignored an engineers question;

"Can you confirm that the pressurization panel is set to AUTO?":ugh:

PPRuNe gets a favorable review in the NY Times.

http://www.nytimes.com/2014/03/13/wo...pgtype=article
________________________

The Wall Street Journal reporter who still stands by the core of his story, is one of the top, if not the top, aviation reporter at the Journal. Martha Raddatz, the defense reporter at ABC News, is very well connected with national security sources. IMO, the U.S. government is selectively leaking information.

Based on the Wall St. Journal reporter's accounts, the pinging lasted for four hours, at 30 minute intervals. So there was power and a functioning communication link during that interval. Depending on whether the U.S. can triangulate the location of each ping, that would give an approximate a location at the time of the last ping. That leaves up to a 30 minute flying distance from the point of the last ping.

According to the Journal reporter's radio interview, he mentioned several times that U.S. officials haven't ruled out the plane landing, or crash-landing on land.

Yes, misread M for H in the abstract. The NIH number is 8.6 hours at -20C with two layers of loose clothing. Recovery time after several hours of -20C is fairly lengthly.

Really? Shouldn't that be the Gulf of Thailand, a much bigger body of water?

Missing Engineers
 

This is what Reuters had to say about the techies. Not sure that anyone said anything specific about the technology they were working on.

Loss of employees on Malaysia flight a blow, U.S. chipmaker says | Reuters

What's "Boeing 777's satellite-communication link designed to automatically transmit the status of some onboard systems to the ground"? Do they mean SATCOM? So, MH370 did have SATCOM hardware?

Also of interest:

"Throughout the roughly four hours after the jet dropped from civilian radar screens, these people said, the link operated in a kind of standby mode and sought to establish contact with a satellite or satellites. These transmissions did not include data, they said, but the periodic contacts indicate to investigators that the plane was still intact and believed to be flying."

Just to nitpick, that's for -30C.

Media if you belive
 

Boeing did state that an airworthiness directive about possible fuselage cracks issued by US authorities in November regarding 777s, which had been linked in some theories to flight MH370, did not apply as the missing plane did not have the specific antenna installed.


However, the Malaysian authorities said reports that more data had been transmitted automatically by the plane after it went missing were inaccurate, adding that the final information received from its engines indicated everything was operating normally.
A report in the Wall Street Journal had claimed that US investigators believed the plane had flown for five hours, based on data allegedly transmitted to Rolls-Royce, the British engine manufacturers.
But Malaysia Airlines chief executive, Ahmad Jauhari Yahyain, told reporters: "We have contacted both the possible sources of data – Rolls-Royce and Boeing – and both have said they did not receive data beyond 1.07am. The last transmission at 1.07am stated that everything was operating normally."
A Reuters report said sources close to the investigation claimed communications satellites picked up faint electronic pulses from the plane after it went missing, but the signals gave no indication where the jet was heading nor its technical condition. They said one engine maintenance update was received during the flight.
Neither Boeing nor Rolls-Royce would comment, citing international conventions on air accident investigations.

I can only quote from subjective experience way back when we were put in small groups into 'the chamber' to experience and watch each other get hypoxic. The chamber was 'climbed' to (I think) about 30,000ft equivalent.

We were given a simple maths test to work out - write down 500 now start subtracting 17 - then one in each pair had their oxygen switched off.

I became woozy and not with it relatively rapidly say 45 seconds or less but subjectively within 20 - 30 seconds was back up to speed when given 100% oxygen. My 'partner' seemed to be totally unaffected when his supply was shut off neatly writing sum after sum.... it was only when we looked after about 45 seconds we noted that although the writing was neat it was gibberish... he also recovered quite rapidly 20 - 30 seconds or so.

So what we learned was onset can be fast and obvious - or fast and not obvious, imagine the FO happily punching nonsense into the FMC. Recovery - on 100% oxygen was rapid. However, we had not spent a long time at height and were young and relatively fit. I expect as with all things biological YMMV.

It could be, it seems to me, that the WSJ reporter still does not have it right.

As noted above and before, it seems that this T7 did not have SATCOM so how could it be transmitting pings to satellites?

What if what was actually pinging was the ACARS/RR monitoring radios but these transmissions were picked up by NSA satellites?

That seems more likely and could explain the confusion of the reporter and his source(s).

I am neither familiar to a great extent with the FBW architecture of the Bus , nor the 777. However, from what I understand it operates ( without Autopilot engaged ) in a form vaguely similar to CWS on my "steam driven" 737, I.E. the aircraft will more or less maintain the same angle of pitch/bank, and within certain limits , return to same if disturbed.

This being the case, given that they had already attained cruise altitude, unless whatever catastrophe that occurred interrupted electrical power such that power to the FBW was disabled, any discussion involving the autopilot is without value, as the aircraft would have continued in controlled flight anyhow until fuel exhaustion.


As a footnote, I think more is known than is being released (particularly radar data) & find it difficult to believe that Satellite data etc would not be available.

Having said that, it took from 5 days to 2 years between finding surface wreckage & anything useful in the Air France accident, so don't hold your breath.

Please read it again, you will note that it says it would be reasonable.. had it ocurred ... it is a proposition that had it, then given this narrow channel of water it would be reasonable to expect that there would be some flotsam. So as no flotsam why are they still busy dreging this narrow water way.

Glossary for noobs.
 

Dear pro pilots and engineers,
This thread has over 4 million views... safe to say it's gone viral amongst non-professionals, regular folks just listening in on a fascination conversation.
So, first, thanks.

I realized I was missing half the conversation, not knowing what the many abbreviations and acronyms that are commonly referred to in these posts (SAR, NIH, PAX, UTC, ACARS etc.) So I thought I would provide a link to a wiki page which could help us amateurs follow along and possibly prevent us from asking dumb questions.

List of aviation abbreviations - Wikipedia

Again, many thanks.

Interesting thing with hypoxia, and in pass this on to all who haven't done a chamber run, YOU FEEL MUCH WORSE POST HYPOXIC WHEN YOU GO BACK ON OXYGEN!

Effectively, your blood flushes the crud that has built up, meaning you get this god awful head rush, dizziness and nausea. Have done the training fairly recently experiencing rapid onset (easy to diagnose) and slow onset (difficult, even when my blood oxygen level dipped below 60%, and I was expecting it). The hazard is people have been known to rip off the mask trying to get rid of the sensation.

By far the worst most dangerous hypoxia was the slow onset, which is very subtle and why good CRM is essential.

Problem is, at 02:00, many of the signs and symptoms are very similar to heavy tiredness, meaning they can be missed.

With the advent of hypoxia simulators as opposed to old school chamber runs, there is NO REASON why airline pilots should not have to undergo this training on a 5 yearly basis, similar to the military requirement.

Did the jet have any form of sat based data comms, ie in flight entertainment or passenger telephone?

I'd suspect, perhaps incorrectly, that a 777-200ER with an airline like MAS would more than likely be kitted with SATCOM.

Just because the airframe in question did not have a particular SATCOM antenna subject to an AD does not mean it didn't have one period.

I would also think the comm system would have to be "logged on" to ensure it was operational on demand.

How would an international airline maintain 'operational control' without SATCOM? VHF/HF voice-data only? Unlikely.

A successful ditching, with no distress beacons, on a moonless night? In an aircraft not able to continue on its way or head for an airfield?

Doesn't sound very likely.

While you'd want to aviate first, if you were going into the sea, having a word with someone might help, at least to let them know what time you were going into the sea, so they could use a piece of string and a ruler to come and find the debris afterwards.

Rather than why the aircraft went down, I believe the real interest at present must be WHERE IS IT.

Given the total futility demonstrated by electronic means to locate any wreckage, it must follow that the search methods will have to be based on the hydrodynamics of the Andeman Sea and the Malacca Straight.

Those interested in the subject may refer to the American Journal of Environmental Science, 2012,8 (5), 479-488, General Circulation in the Malacca Straight and the Andaman Sea.

Here is a link to it.

https://www.google.co.uk/url?q=http:...W1Bsn20njh-ifA

capn p

As an end user I reckon the T7 handles much the same as most other "normal" non FBW aircraft I've ever flown but with the addition of one or two knobs and whistles (like pitch/power couple taken out). If the aircraft is trimmed properly for the IAS at an attitude then disturbed from that datum attitude it'll eventually return to that datum (blimey, memories of CFS S&L 2) just like a Cessna or a JP - it doesn't do anything magic like pop straight back to the datum attitude if the stick is released with the aircraft close to datum ( if that's what CWS does?) - Interesting point and I guess we need someone with both 737 and 777 time to referee.

jehrler: Re SATCOM
 

I believe that this particular T7 DID HAVE Satcom, just not the Satcom antenna per the recent Boeing AD. Not the same thing at all.

Because the airline will not let you onboard without a visa otherwise.

I am reluctant to post on this topic (being very old and retired!) but I have a reasonable amount of flying experience (civil & military) and have flown in that part of the world. My knowledge of the 777 is nil but I have a reasonable idea of what is available on equivalent modern airliners. No idea of the "revised" flight path of MH370 (like anyone else!) but it would appear possible that it did not impact (if it did) in the sea, but may have continued on a track that put it over some fairly inhospitable land terrain (Jungle/mountain). This would certainly pose more problems in the search. Just a thought! (As mine are with the NOK!)

As the days wear on, the issue of any debris drift does indeed become more and more of a factor. No one knows where the plane is, so I'm just putting this out there as a go-to reference in case something eventually turns up:

Real-time Navy model website for sea-surface temperature and currents:
HYCOM 1/12 degree page

The Indonesian Flowthrough and Indian Ocean are the most relevant sectors. As a point of reference, 100 cm/s is equal to 1.9 knots, and 1.9 knots is 46 nm/day (EDIT: typo on 1.9, fixed, sorry). Most values are well below this.

Chart for the point roughly halfway between the crash and now, as a general reference since there is little day to day change:

http://www7320.nrlssc.navy.mil/GLBhy...spdcur.001.gif

BBC news are reporting that the Malaysians are stating that the Chinese satellite images are not related to the crash.

BBC News - Malaysia plane: China debris images 'not connected'

Also interesting is that the Malaysians are joining with the Indian navy in searching the Andaman Sea, to the west of virtually all of the previous reference points.

Very interesting.

GarageYears,

Could be but if so then, as hamster3null noted above, what is the

??

Which systems would these have been since it seems that the RR one is not satellite based and earlier posts claimed neither was the ACARS?

If it did have such capability and these systems need to ping the satellites (even when not transmitting any data) ala a cell phone, then why has it taken this long for anyone to notice that these satellite signals lasted for 4 extra hours after the last communication?

I'm sure anyone who may have received a communication from the aircraft was checking their logs on Sunday, but any relevant information takes time to percolate through the investigation.

Thanks Lonewolf 50. The reason why I posted this up was to show that the seasonal variation in the hydrodynamics of the region is such that by now the Malacca Straights would have revealed its dark secrets and that The Andeman Sea would have carried it well out into the Ocean.
But had I been a betting man I would put my money on the Indian Ocean.

According to the RR engine ping communications, it stayed aloft for 4 hours. Not three, or five, but four. That is pretty exact information.
Actually, that is the most exact information I have seen for quite a while.

Asylum Seekers and Stolen Passports
 

An Iranian seeking asylum in Western Europe needs a visa in order to get to Western Europe. He's unlikely to get it if the Entry Clearance Officer suspects he will ask for asylum.

Yep, that's why I'm struggling with the "MEC damaged,selectively and the aircraft flew for hours" scenario....

In fact I'm not really buying any mechanical/technical scenario I've heard so far ..I'm at a complete loss.

How about the exact information that shows the original WSJ reporter correcting their statement that it wasn't actually data related to RR engine monitoring?

MG23,

I understand but what seems to make this a bit of a long time to search is that, as noted in earlier posts, these communication devices have the equivalent of a MAC or IMEI address allocated based on the airframe.

This would, I imagine, make searching the logs much quicker as there would be an identifiable characteristic to a ping.

I also wonder if one can use triangulation or simply dead reckoning from the satellite(s) contacted to get a feel for where the aircraft went.

Yes, a commercial fairly easily available (although likely some flags would be raised) wideband RF Jammer with the sort of power needed would fit into a smallish suitcase, size in most cases here is proportional to power output and frequency range required.

It still has to be validated, then passed on through the correct channels. That takes time.

Imagine if someone spoofed a signal, the people receiving the signal didn't validate it, announced it immediately, and that drew the SAR effort a thousand miles away from the real site. Not a good idea.