Already stated, there are other ways of determining engine running status other than via acars....

Engine Health Monitoring
 

There is so much utter tosh being spouted about what data was sent from this aircraft I'm not surprised that most truly professional pilots have packed their bags and left this thread long ago!

As an ex-employee of an airline that actually used this facility let me try and explain how this generation (mid to late 90s) actually works. I'm not an engineer so fine detail may need some correction from genuine experts.

Data snapshots of engine parameters are sent, depending on how the airline has set up its support package, either directly to Rolls Royce or via the airline. This is done via ACARS using, typically, VHF radio link, though via satellite if specified. which for this generation of aircraft is unlikely.

Usually, these snapshots are taken and transmitted in near real time for Take-off climb and cruise. If the aircraft is out of range, the information is stored and transmitted once a suitable ACARS link is re-established. There was a New Scientist article being referenced yesterday by many media that stated that Rolls received two such data bursts: Take off and climb before ACARS link was routinely lost. Comments by the Malaysian defence minister and Malaysia Airlines CEO at Thursday's media briefing would fit into this stating that the last data was received just after 0100 local - well before contact was officially lost and less than 30 mins after take off.

All the airline and engine manufacturer expects from this generation of engine is time-stamped data on temps, pressures, shaft speeds, fuel flow, mach number etc.. Not where the engine is.

Such data would routinely be passed on to investigators and involved parties in the event of a serious incident or accident. If an official investigation was underway or anticipated, then this info could only be made public via the investigating authority.

"perspective people" What should be glaringly obvious by now is that Malaysia have no dedicated maritime search and rescue capability. A situation I'm sure will change after this event.

MH370 has crashed, probably due to a fire or some other catastrophic event. It will be located within 300 miles of it's last known position, the closer it is to that position the more embarrassing it will be. The debris field should be washing up on coastal beaches in the next couple of days.

Patience, it will be found, That is a certainty.

ABC News now reporting; systems were shut down at different times, indicating not a catastrophic or mechanical failure as much as a human being decision.

TURIN
 

I noted your original post saying that the crew O2 bottle fittings were on the aft side of the bottle and thought that the the wind was blown out of my hypothetical sail.

However. I have done some more research on the QF30 incident and found in the Australian Transport Safety Bureau report that the bottle was propelled upward through the cabin floor where it damaged a door handle and some trim, then dove back through the hole in the floor and exited the aircraft via the hole in the fuselage... RUBBISH??? Thats what I thought.

However. There is a photo tab on the web page. The last photo of the set is of an O2 bottle sized hole in the floor panel directly above the hole in the fuselage.

The Pax O2 bottles in the 747 fwd cargo sidewall stand vertically, plumbing on top, so the base end must have failed.

The missing bottle was not found onboard.

Ref: Australian Transport Safety Bureau website

Side Menu: Aviation safety investigations and reports

Search: July 2008 and QF30 is top of the list

All... My hypothetical structure of events is purely speculative, as most here are, until we get some real facts to work with.

Thank you. Blox in.

It's really quite amazing to see all this idle speculation and contemptuous remarks about the perceived inability of the local radar facilities to track this one (assumed) primary track with any degree of success.

Your memories are obviously too short to recall that the 9/11 Commission concluded that the worlds richest and most technologically advanced country was unable to track and intercept FOUR allegedly primary returns over the US mainland on that fateful occasion.

Can we stop this racist and arrogant discussion right now and, with a little humility, accept that such tracking capability is most unlikely to be operating/available in the affected region?!

And the idea that a T7 will impact the ocean and hide itself in the sand/silt like a stingray is indicative of the febrile imagination of some of our posters and leaves me in despair about our profession, if indeed these fantasists are Pro pilots??!!

ACARS Data
 

Perhaps I've missed something,please forgive me if I have. However, my understanding of ACARS TX'd from MAS 370 is that there was none. So why are so many people postulating what can be inferred from the TX'd data?

My understanding:

Malaysian Airlines said there was no communication from the AC after contact was lost.

Boeing said that no data was received from the AC after contact was lost.

RR has said the no data was received after contact was lost.

US sources have said that the AC may have flown for 4 hours after contact was lost. They suggested that this was because satellites received "faint pings" from the AC's monitoring system after contact was lost. However, they also clearly stated that "no data was received from the AC."

So again, I ask; Am I missing something?

There are a large number of loss of comms incidents all around the world everyday and there are procedures that are followed in these cases.
Sometimes this could escalate to aircraft being intercepted.

However, there are guidelines for being intercepted and it doesn't result in an aircraft being shot down with no special reason.. (unless someone is very trigger happy).. YouTube the video of a Vueling being escorted into Ams (I think) after being intercepted. Yes, he got escorted but he didn't get shot down as he complied with the instructions of the interceptors whether that be via radio or via lights / wing signals.

So sorry.. but that just doesn't make sense.

What benefit is it to the investigators to publish what the cargo was? - None, so they won't publish it.

data
 

"no data was received" does not mean there was no contact.... There could have been a "handshake", but no data received. Semantics...

just tried google's gps tracker and got a response including coordinates>
I am not sure what this is showing, - just the last known position or something More?

I APRS object MH370 - show graphs
Map loading...
Source callsign: K7GPS-3
Comment: Initial last ctc of B-777. Where is it?
Location: 7°33.55' N 103°42.63' E - locator OJ17UN54GE - show map - static map
Last position: 2014-03-13 23:00:11 UTC (11m19s ago)
Last path: K7GPS-3>APU25N via TCPIP*,qAC,T2QUEBEC
Positions stored: 1
Others sourced by K7GPS-3: Balloon IRLP-7844

Are there any good ideas as to why this misunderstanding about 4 hours of ACARS data could arise? Is there some system in the middle, such as the airline's server or the satellite account logs or anything like that, which could show what looked like activity from the aircraft even though the aircraft did not send data?

Very trivial example: I can die at 4 o'clock and two hours later someone can see an ad on Facebook with my name being listed as "OlaM likes Boeing 777s" time stamped 6 o'clock- it seems like an act done by me after death, but it's really done by a computer.

Less trivial example: You purchase something on your credit card March 8. You die on March 9. Your statement says you paid for it March 10. Bought by a ghost? No, March 10 was the first business day after Saturday the 8th.

It seems this case is plagued by random statements made by ill-informed or misunderstanding personnel to crazed reporters and the hurtful conspiracy effects will linger for a long time. So what about ACARS can be misunderstood in a way that makes you think the plane flew 4 hours longer than it did?

The answer to that is best posed to whomever in the US of A released that info to the media. I suspect they not wish to tell you, citing "methods and sources" but a brief explanation has already been provided in this very thread. Less than ten pages back.

We don't have to buy it, nor believe it, but it's there.

ACARS Data
 

@CommanderCYYZ

Others have addressed your question a few times, but to recap: the satellite radio system "pings" the satellites to maintain contact even without sending otherwise useful data. So, by saying in effect "Here I am, are you there?" repeatedly, the system is ready, the satellite is known, etc., for when real data communication is needed.

So the reports that no additional engine data was sent can be true, along with the 4-5 hours of "pings".

@Olam
 

The thing is, there was no data TX'd. What appears to be the case, according to reports, was that ACARS system on the AC was sending RTS pings periodically but never connected. The reason given was that MAS don't pay for that level of monitoring, so it was reported. However, the "pings" would seem to suggest that the AC was still alive 4 hrs after contact was lost.

Correction - Boeing and RR declined to comment on the reports that no data was received. Which is per process - Boeing and RR are effectively under a gag order and will not comment on the investigation.

BTW, passenger oxygen is good for ~15 minutes. Crew oxygen somewhat longer than that.

As I recall, cargo information has come out quite quickly on some occasions in the past. I distinctly remember it coming out that Ft 800 was carrying a large quantity of glitter, of all things.

Sat coms, 4 hours
 

Here are what now seem to be almost facts.

The ACARS system for the airframe did not have a satellite subscription.
The ACARS system for the engines did have a satellite subscription.

The satellite path is used when there is no VHF path available.

The engine ACARS only sends when a significant event takes place. There was no event after the top of climb and so no further messages were sent.

The Engine ACARS satellite coms system "pings" the satellite every 30 mins.

Therefore:- Since about 8 pings were received and logged the engines ran for a further 4 hours after last message at top of climb since a shutdown would have resulted in an ACARS message. The exact time is not known of course.

By the way. I am far from satisfied that the satellite system used is Iridium. Due to the low earth orbit and rapidly changing overhead satellites I would have thought that the ping might need to be more frequent.

Mandatory GPS Tracking
 

General aviation aircraft have been doing this for years. I know of at least 3 vendors who offer such service at modest cost: Spidertracks, Spot, and InReach.

Basically, a unit on the a/c sends its GPS coordinates every 10 minutes or to so a satellite which relays it to the tracking company's servers.

The airborne unit often goes on the glareshield, and it includes its own battery that lasts for a few hours if power is lost.

Well, since a lot of people here doesn't seem to understand what's going on regarding the ACARS/SATCOM stories in the press, let's recap what's going on regarding the new information from the US.

- MAS ACARS comms only work thru VHF since they chose not to pay for the extra fee for ACARS SATCOM link
- That 777-200 is SATCOM equipped
- What was found by US Government services (NSA, or maybe they asked Iridium directly to check the logs) is that, since the a/c ACARS system was out of VHF coverage, the system tried to connect thru SATCOM. But since MAS doesn't have a contract for that, connection was rejected, but remains a trace in their logs.
- That means that what they actually found is the log indicating every time the aircraft ACARS system tried to log in thru SATCOM and failed due to the lack of contract for that. Since the ACARS system onboard that specific aircraft tried for 4 hours after its disappearance to connect via SATCOM to the ACARS network, it means the aircraft was, at least, powered on and, since not found anywhere yet, probably flying.

Sorry if I wasn't clear enough, I tried to write everything down ASAP...

I have an IT background, and according to all the available sources, this is my interpretation of what's going on.