Some points about the inmarsat lines of position.

- According to spec GSM must infer distance between base station and user equipment via round trip times with an acuracy of better than 550 metres. I see no reason why Inmarsat should perform worse.

- In the first 2 hours of the flight MH370 was in range of two satellites (POR/IOR). During that time two intersecting lines of position should be available. From todays PMs Statement:
I.e. primary radar track and the positions from inmarsat correlate. That is what gives them confidence in the data.

- What was shown to the public was only the last known line of position. More lines from during the flight must be available.

- If sombody wanted to land that plane somewhere (I don't believe it) he might wanted to do that with first light. As we are close to Equinox the night/day border is almost parallel to the meridians. Longitude of the day/night border at 8:11 Malay time was somewhere close to the Andamans. Further west it was still dark.

The reality is that likely the band is not so narrow. Calculating distance from >30000km requires very accurate timing. If they are off by a millisecond, they they could be off by hundreds of kilometres. So the reality is the potential arc of last known locations could be much wider, but these are what they determined to be most likely given the last known position of the aircraft.

This will probably be deleted, but I thought straight away it was an odd thing to say The expression "all right" is so English, not the sort of thing said by a Malaysian. If he had said OK, I might not have noticed.

...tired of life and a need to make a statement by going down with a big bang.

Hi Jeanlyon

I am unsure if you ever lived or visited Malaysia, which was a colony of the British, and where English is widely spoken together with their language, Bahasa Malaysia. The average Malaysian speaks decent English IMO so much so applicants seeking to migrate to eg Australia, do not have to go through the IELTS testing, given as an example.

Undubbed content from the US and elsewhere forms a large portion of openly available TV channels in Malaysia.

It would not surprise me if he had indeed said that. I would think that the captain was educated in an English medium school and took all his professional courses in English.

Disclaimer: Born in Kuala Lumpur, living in Switzerland for years.

http://www.universityworldnews.com/a...10408183436105

http://asia.nikkei.com/Business/Tren...n-Asia-ranking

If this episode was/is due to loony pilot(s), does this mean that the sensible flight ops departments of sensible airlines will regain control of flight crew recruitment??

First move would be to lock out the dreaded H R departments with their obviously ineffective psychometric tests, and to introduce proper psychobabble screening for current and future pilots and wannabes.

This could provide much needed employment amongst the shrinks shortly to be made redundant by the UK health service and introduce a complete new raft of certificates for EASA to charge for issue!

Bearing in mind that the large majority of air accidents are HF related, it might also reduce the nastys which occur due to the faulty
programming of the space between the ears of the 21st century
bonobos occupying the front seats, of whom I was one til recently?!
:suspect:

From elsewhere, last possible location map with Jindalee overlay:

http://i.imgur.com/8PY8ywk.jpg
So the Aussies 'should' be able to rule out the lower segment, depending on possible error margin?

http://www.flyertalk.com/forum/22527773-post4170.html

Return 2 Stand

What about superimposing a circle, radius 3000 miles, centred on the South China sea position and seeing where it intersects the satellite arc?

Not buying this suicide angle, why wait 2hrs and why not nose dive it from FL370?

B777-200 avionics compartment photos on the web
 

United Hanger at SFO. - Wings900 Discussion Forums

(found these online, gives an impression)

If so it seems he chose a remote location for his 'big bang'.

Why fly all that way just to commit suicide?
 

Whilst logic might not be the strongest suit of air pirates, or rogue crew, or terrorists, neverthless it seems to defy all reason for a conscious crew or even a conscious hijacker to fly on for hours if all they're going to do at the end of it is crash the plane.

Surely the most logical explanation is that the plane has been flown to a specific destination .Clearly that destination isn't an airport - otherwise we'd all know about it by now and wouldn't be having this conversation.

But the destination could be a kind of "Dawson's Field" landing strip somewhere - similar to that used by terrorists in the 1970 triple hijacking. Dawson's Field was , I think, in Jordan - an unmanned desert field. All that's needed is a flat salt-pan somewhere - and given the huge number of possible landing grounds within the now-extended search area it'll take a while to locate - even from satellites.

One other thought - they wanted to crash onto a specific city or target - but ran out of fuel en route. Perhaps maths wasn't their strong point either.

Anybody know what the US has on Diego Garcia radar-wise?

I'm not sure why you think this. Perhaps you can explain your thought process.

With the supplied information, I think the southern route is still plausible. You can't discount it until there is data to support removing the possibility.

1. You have data supporting the poss. of this route.

2. You have an AC that potentially flew to fuel exhaustion. This adds another element to consider. The last data point when the AC could have potentially run out of fuel, is telling. If fuel exhaustion could be ruled out, it would be one less variable.

3. You have no SAR team or anyone anywhere spotting anything from the AC.

4. No pings from any transmitter (ELT, FDR, etc.)

5. You have very deep water.

Phraseology: full context?
 

I wonder what the full context of all the transmissions is? Is there a recording or transcript that includes all comms up until that point with a sense of time between tx?

I live in San Francisco Bay Area and I've heard, just as a for-instance, from the lips of Very Big Airlines pilots, the following or similar, after tower issues a new frequency change instruction to a departing flight: "Aloha, switching," with the tower replying, "Aloha."

No freq read-backs, but apparently the planes continue on to Hawaii without incident, dozens of times each day.

The nonstandard in the above example was preceded by a bunch of tx that were more standard, all contributing to help everyone build a mental picture of what's going on, with the signoff being casual. All frequencies are well-known to all parties. And that's a tame example. I've heard way more nonstandard stuff that would baffle a foreign pilot, like instructions to helis to hold over the 'stick (Candlestick park, a sports stadium north of the airport). You could argue these practices threaten flight safety, but frankly SFO does ok safety-wise given flight volume.

As others have pointed out if the route is frequent and both pilot and tower are local, this happens even more. It's human nature.

Think about the shorthand you develop with your loved ones. Other people outside your family may not always understand 100%, but it doesn't mean you do it with evil intent. It's human nature. Technically I should have written, "It is human nature," because given the international nature of this forum, some people may have a harder time parsing contractions. In this case I'm gonna risk it and figure 99% of readers will have little difficulty understanding contractions and the odd nonstandard word. I like to live on the edge.

Point is, in order to make the judgement that this transmission was anything other than normal, we would need the full transcript, PLUS enough other transcripts to judge how this particular pilot tended to phrase things.

This could be completely normal for him, or not. Bit I'm uncomfortable plucking one phrase out of what is a conversation, and coming to specific conclusions.

Happy to revise my opinion if it is shown this was really out-character.

jm

This is a new one on me, could you provide a reference? Are you thinking of Tex Johnston's barrel roll of the 707 prototype over Lake Washington near SEA in 1955? Or Harvey 'Hoot' Gibson's TWA B-727 upset with pax onboard in 1979?

Looking at the MH 370 captain's purported Facebook page, it appears he is a techie and a foodie (is it mee goreng and mee siam in the pictures?). It looks like he has pulled the control panel out of his refrigerator to replace or repair it. He also builds his own computers, I agree with his choice of an Asus motherboard and an oversize power supply. The parts seem to have been purchased from a U.S. vendor (Newegg?) judging from the domestic Priority Mail box. I can't quite make out the mailing address in the picture, perhaps it is a layover hotel or a friend in the States.

As far as his political rant supporting a candidate accused of sodomy, he seems to be advocating change at the ballot box. And, in the U.S. these days, if a candidate said anything negative about sodomy they would be roundly denounced as a homophobe by the mainstream media. Not that there is anything wrong with that as Seinfeld would say.

Nothing conclusive from what I see but it does indicate that he would perhaps have in-depth knowledge and understanding of avionics and aircraft systems. I can also build computers and have recently changed the microprocessor board on my home air conditioning system. But I couldn't tell you what the power supply is for VHF ACARS, SATCOM, ADS-B or HFDL or where the circuit breakers are located unless mentioned in a QRH checklist. Of course, I could find out, assuming the company aircraft manuals weren't too dumbed down as is the current trend. It would be interesting to know if Captain Shah had 777 maintenance manuals and wiring diagrams at home.

I get real fascinated by aircraft systems about once a year when I have training.

None of these comments are meant to be an indictment of the crew but, as a long haul Boeing pilot myself, I now think these areas of crew background should be closely investigated.

I have put an explanation, description and detailed maps of the ``corridors" up at the following URL

MH370

And the maps from that page

http://www.csse.uwa.edu.au/~mark/per...0/northArc.png

http://www.csse.uwa.edu.au/~mark/per...0/southArc.png

Hi, yes I did know that about Malaysia. Even so, it's a particularly English expression, not often used these days. OK being more normal. I too was surprised that there was no mention of the new frequency, but then I did stop flying a few years ago, although I was married to a pilot and he also finds it strange.

Not quite:

http://s8.postimg.org/ye87yekz9/isat.jpg

looking at the arcs in #4019 by "Return to stand).

Would I be correct in assuming at the point in time the aircraft disappeared off Penang the previous or next ping would show the northern arc in a more southerly location cutting through that point and the southern arc would be correspondingly further south and out of range for hrs flown.

Now it is reasonable to think the next ping placed them in the Andam /bay of Bengal area as resources were sent to both ends of that arc.

At this point in time the southern arc would also have moved northwards but still be out of range for hrs flown,

To me this suggests the aircraft CANNOT BE IN THE SOUTHERN ARC.

I am assuming the two arcs would always be the same distance apart as the satellite is geostationary is this correct.

Would be nice if someone was able to post a graphic with these two arcs and jindalee in the south and primary radars in the north.

For those that mentioned possible SLF cell phone contacts....

That is unlikely.

Cell tower antennae are usually tuned to have optimal performance in 120 degree arc by 60 degree or less elevation. Depending on the frequency and a ton of other factors, practical range is 2 or 3 miles at best (that goes for SMS as well). On an airplane that means something like 10k feet since slant range will be approaching 3 miles, but usually much less because of being outside of antenna cone and an aluminum airframe does a wonderful job of attenuating signals.

Best you can hope for is a stray tower got a stray ping, which would give you a circle of a few miles. Now LTE relies on GPS for timing, but not sure if location data is a part of the ping data packets, and I'm not even sure if that data is saved. I don't administer towers... I just build/upgrade/fix them and leave.

Thanks.

OK so only the "last" ping is on that arc, am I correct? So what about earlier pings? Would they not help?

An incapacitated one?

And can we stop all this talk of the 'precise flight path' flown from 'waypoint to waypoint' carefully 'avoiding various areas of radar cover'.

The track is just a guess, based on a handful of satellite pings and some primary radar returns. In the absence of any more accurate information, it could just as easily be the track flown by an unconscious crew on autopilot without a heading selection, until fuel exhaustion. :(

Exactly. I doubt its a perfect omni-directional antenna. Heading/pitch/roll will affect the radiated power hitting the satellite, as the direction of the antenna on the aircraft changes.

That can be modelled however. I suspect there are some very clever people and alot of CPU cycles being burn trying to model possible flightpaths based on the data available.

I know something about mental health and suicide. Anyone who wonders why someone would go to such lengths to mask a suicide, doesn't have that much familiarity with suicide.

It is actually reasonably common that someone commits suicide, but tries to disappear rather than be remembered for the act of the suicide.

Also the willingness to murder innocents in the process is not quite so rare as people are making it out to be. Ask any policeman about what they think really happened in many head-on collisions that are classified as accidents.

If that is what happened here ... big if .... the elaborate nature of the plan may be mindblowing, but the essence of what is going on isn't very mindblowing.

I must say that I've been waiting for someone to say those two words from the very beginning, Unixman in 4043. It was a reported quote at the very beginning from Iran claiming that the Americans had kidnapped the aircraft that just made the island jump into my head with no reason that I could rationally justify to anyone. Since then the suggested increase in flying time and mention of the southern Indian Ocean brought it back to mind. They must have some pretty hot radar there too, no?

Define ping
 

I've researched the underlying comm protocols a bit. Can anyone here clarify whether the "ping" refers to the AMSS R channel protocol transmission from AES to GES?

I am disappointed at those in the industry who believe we hold trade secrets that will effectively stop future 9/11 type events. As an airline pilot who sees continual lapses in judgement among flight and cabin crew in security protocol, I can see we are in a bad place. Never Forget: That was the adage we subscribed to a decade ago, yet now it seems we have replaced it with "history repeats itself", which of course it does...

Someone took the time to highlight a massive security threat with regards to the 777 E&E. Given that this information will find its way to anyone who wants it, the only remaining group left out is the general public and they're the ones who can demand change. There is only one reason this threat still exists - it's a financial burden to fix it.

Yes, only the last ping was somewhere on those arcs

it would be helpful for amateur sleuths to have have information about the earlier pings.

However, I am sure the real SAR team is making good use of them.

No, I thought it was the 'roger that' expression.

Okay for the movies, but not to be seen in CAP413.

Maybe the Captain trying to discreetly raise the alarm or the 'alternative crew' already in command?

Agreed, but I wasn't talking about attempts to connect at 10,000 feet, I was talking about practically every passenger in the last minutes and seconds of the flight desperately trying to speak to or text their loved ones.

If this was over land and anywhere near a mobile network then there is a strong possibility that at least one cell somewhere would have responded.

tip of northern arc = kunming
 

has anyone mentioned on here yet that the tip of the northern sat arc (or "corridor") happens to be really close to kunming, where fundamentalist separatists/extremists attacked a railway station recently?

Well, if the choosen option was indeed the Northern Arc, we could have here a big obstacle, "greater" if it was flying lower, no radar and under the cover of night simply called "HIMALAYAS", just my 2 cents...your opinions?

@OldObern

I'm afraid I'm struggling a bit to understand what you mean - can you clarify? When you say that do you mean that the plane's position would have been on the 50-degree arc rather than the 40-degree?

Much mention about one of the pilots hijacking the a/c but what about any member of the crew? Who were the staff passengers - any aircrew amongst them?

IF this incident was a carefully planned and executed hijacking, and IF the hijackers aboard the aircraft were coordinating with accomplices at some destination as yet unknown, there is no reason why they would have to use Inmarsat or Iridium or any other type of satellite network to communicate with their confederates.

The 777 is equipped with at least two powerful HF radio tranceivers, capable of operating on any frequency between 2 and 30 MHz. HF employs simple point-to-point communication directly from transmitter to receiver, and does not require any external network whatsoever. There is no digital data encoded in the signal that could identify the source of the transmission - it is simple single sideband amplitude modulation - a technology that has been in use for decades.

Though an airliner's HF radios are normally used to communicate with ATC facilities on specific frequencies in assigned band segments used for aeronautical communications, there is absolutely nothing to prevent the HF from being tuned to a discrete pre-arranged frequency somewhere else in the 2-30 MHz spectrum - such transmissions are unlikely to be monitored or intercepted in real time, and even if they were, localizing the exact position of the transmissions is quite difficult, due to the nature of ionospheric radio propagation that makes long-distance communication possible at HF frequencies.

Assuming it was indeed a coordinated hijacking, with the aircraft destined for a secret landing at some unknown location, the people awaiting the arrival on the ground would need nothing more than a battery-powered HF transceiver, and a simple long-wire antenna to communicate directly with the aircraft, even if it was still hundreds or thousands of miles away.

As a licensed amateur radio operator, I have done this many times while backpacking in remote areas - communicating with other amateurs around the world, using extremely simple and portable equipment.

Diego Garcia Radar Range
 

For reference - JORN in Australia publicly admits to 1,000 - 3,000 km for their OTHR system. Range would tend to be longer during the night and around dawn, but HF propagation is hard to predict.

JORN

Northern route
 

@ETOPS

SIA68 intersects with the last Northern radar ping at UTC 00:11 around Ashgabat. Probably others have had the same thought...

You are right, as many years ago when I was first flying, I used to very occasionally ask the flight deck if I could use the HF radio to call my husband, as he was a ham. Highly illegal from an Amateur Radio point of view. I recall I was over the South Atlantic at the time heading for Rio. We had a specified time for the call :-)

No they don't use those phrases either! :)

Not quite the point of my Post.

In the whole of my flying career I've never heard 'roger that' being used by a line pilot. Maybe things have changed in the past few years, but not in my experience?! I think the airline training Captains might have a wry smile and then correct the phraseology used.