pilotmike... ISTR it was the Malaysian speakers who said the FO was "in charge". I do understand the protocols, I assure you. In the past I have occasionally had to ask to speak to the captain :p

My reference was to a BBC summary of many days of chaos and gibberish. Would anyone care to summarise this thread? ;)

Turning off the transponder in-flight
 

I'm trying to sketch a workable technical solution that makes it all but impossible to go invisible the way MH370 did.

From the various comments, it's evident that there are indeed legal occasions where the transponder could be turned off in flight. Malfunctioning transmissions and equipment fire are the two main reasons. However, ALL these cases imply a coordination with ATC so that ATC is aware that the transponder is off.

Or can you think of any legal situation where the transponder can be switched off without making ATC aware of it? Please tell?


Now then for the solution sketch of handling the illegal use cases using a "Smart Circuit Breaker" at least for the transponder. This is a proposed "intelligent" CB networked with the plane's systems and ACARS. What it does is send alerts to ACARS as follows:

1) Manual intervention alert: If manually pulled, it breaks the current and sends a message to ACARS "CB123 for equipment xx was manually pulled at time yy:zz".
This is for the case that a) someone tries to illegally make the plane invisible, OR b) a fire or other event when the crew tries to manually isolate a faulty equipment.

2) Overcurrent alert: If triggered by overcurrent, it breaks the current and sends a message to ACARS "CB123 for equipment xx was triggered by overcurrent at time yy:zz".
This is the intended normal function of a circuit breaker, to protect the electrical system in case of a short circuit or similar.

3) Turn-off alert: For a smart CB associated with a piece of equipment that normally is never turned off in flight (such as a transponder) and triggered by current that stops flowing (or drops below some normal idle current), it sends a message to ACARS "CB123 for equipment xx was triggered by turn-off event at time yy:zz". In this case it will not break the circuit, just send the alert.
This is for the case that someone illegally turns off the transponder in-flight from the power button.

4) For a smart CB associated with communication-critical equipment such as ACARS itself, VHF,or Satcom, it waits for a certain delay to allow ACARS to transmit the alert message by VHF or Satcom to the outside world before breaking the circuit.

Summarizing: This solution allows manual depowering of the transponder, but will send out alert messages if done in-flight. Moreover, existing transponders would not need to be modified. The engineering challenge would then be to design a plug-in replacement for those existing CBs that would need to be replaced, as well as the interface to ACARS.

The complete solution obviously also must include software mods that will cause similar alert messages to be sent out if someone dectivates the ACARS in-flight. This sketch focused only on the transponder.

Doable? I think so. Just a daydream? I hope not. Good solution? You tell me.

"many days of chaos and gibberish" :E:ok:

Satellite Pings

I see it now, had to sleep on this.
Satelllte ping says, Mary are you there, eight Mary's respond, because I know where Mary's 1 through 6 and Mary 8 are, the one I'm looking for must be Mary 7

Very Clever

This thread is growing faster than I can read...

Quote "the authorities think the last two pings came from the same location and that the last ping was on the ground." /Quote

Is that confirmed?

And - hasn't the BBC reporter who brought (I think) the story of the oil rigger stated that it turned out to be false? So why is this still discussed. I think we need a summary of the current facts and the possible implications.

We all know this is an unprecedented event, pilots, SLF and all other ones as well. And unprecedented in ALL aspects, the actual event and the reaction of the authorities, first and foremost Malaysia itself, which acts as if not coming clean fully.

@snowfalcon2

You might be better off worrying about how to see if the pilots have shut down the engines in flight.

SOUTHERN ARC TRACK
 

Any shipping lines along that southern arc trajectory that might possibly be used to play a role in the SAR?

@MPN11My dig was at the reported presumptions, not you!:ok:

I'm one of those folks who tries to avoid the sim, since it is too much like work to me. Still, I should look into getting some of this software to practice FMS work and the like for my annual training. You get some wacko route modifications that you will never ever see in the real world but the folks in the sim building think are somehow essential. Of course, you never learn how to do an offset while still on the SID in China for example.

I certainly agree with Teso that legacy protocols like ACARS (and even worse maybe, CPDLC) have little in the way of security and authentication. They were designed years ago to replace civilian voice procedures which are similarly unsecure and weakly authenticated.

I'm sure the network engineers will remind me that security and authentication can be added at the transport layer as with the Satcom transmissions discussed here. However, VHF ACARS is still usually sent in the clear with little security other than the formatting and some internal airline codes.

There are secure ACARS protocols available, in my observation, they are still not in common use:

Avionics Magazine :: Securing ACARS: Data Link in the Post-9/11 Environment

From the article above:

Here's a couple of ACARS messages I posted here years ago, logged with simple equipment and software:

http://www.pprune.org/rumours-news/6...tml#post593825

The hack of simulated aircraft systems with an Android phone may have been an overstated media stunt and perhaps not a possibility with MH 370.

However, as we go more and more digital on the flight deck, this computer and digital comm stuff is a threat surface we really need to consider in my opinion.

It does seem unlikely - and extremely difficult if not impossible to actually do - but we've already seen that radar coverage is a bit lax in the middle of the night. If an operator did see what appeared to be a 777 shadowing another 777, what would be his first instinct? I suspect that it would be that he's seeing some sort of echo or ghost artifact, rather than that someone really is trying to do that in a jumbo jet. Chances are, it might be ignored - or that the radar repairman might be called.

Well, after all the movie-plot theories, mechanical possibilities, crew conspiracy/suicide suggestions; after all the pings and turns, descents and climbs, and despite volumuous discussions of switch positions, radio phraseology, and aircraft systems, we're still left with nothing more than what we started with:

An extremely reliable airplane, maintained by a reputable airline, flown by a professional, qualified crew, on a normal route with no adverse weather.... that inexplicably doesn't make it to its destination and disappears.

Since everyone has their own opinion as for why, I'll offer mine and make this my final post on the thread.

A security failure at some point resulted in a person or persons, as yet unknown, interfering with the flight crew's performance of their duties, for the purpose of terrorism. The crew died trying to thwart that effort, resulting in the tragic loss of the aircraft and all on board. As for why no group has yet claimed responsibility, they failed. Whatever building or major city was their target is still intact. No terror group will advertise their failures.

Fyi:
ADS-B is only available on the L Transponder on the 777 (with standard fit).
As soon as the R Transponder is selected the aircraft is unable to send ADS-B info.

Disabling ACARS (both VHF and SATCOM) is very easily done via the COMMS pages.

Would be interested to see the parameters of the engines that RR received for a good view hours.

If someone has punched in LITEX & GIVAL into the FMC there is a good likelihood that incapacitation isn't on the cards, more a considerate attempt to go somewhere.
FYI: (that airway is used lots by all airliners to transit over Port Blair towards NE India, VOMF AND VOCF FIRs

Jugofpropwash

to try to shadow a 777 would be not possible ( read some pages back ). Also military operators do not look at the blips but track symbols. Depending on the radar you would get two very overlapping symbols (one identified, the second not), drawing attention to the situation.

The best chance to fool the military is to fly like everybody else on a published airway. Chances are best you will not be discovered, even if not automatically identified. Unless there is a very good relationship between military radar and ATC, nobody will raise an alarm in the middle of the night.

Once again, ACARS DOES NOT DO POSITION REPORTS WITHOUT BEING LOGGED ONTO ADS!!!! The ground systems cannot setup a contract without the aircraft logging on.

If the pilots haven't logged the ADS onto the FIR ADS address the ACARS will not send position reports. ATC cannot log on to the aircraft without the pilots requesting it first as far as I know.

There seems to be a common misconception throughout this thread that ACARS is sending back position reports constantly. It doesn't.

Some air and some ULDs.... that's what I think was in the cargo hold. :E

Like the mobile phones, the meteorites and every other theory under the earth that has been mindlessly discussed here, my answer is simple.... until proven otherwise by hard facts, the contents of the cargo hold had nothing to do with this incident !

For fear of repeating what I said a mere 3114 posts prior to yours.....

Well, sure they could perhaps, maybe do something to something.

But how much could they do to safety critical systems ? I suspect the numbers plummet dramatically, if not to zero.

How much could they do to safety critical systems that the flight crew could not overrule by flicking a switch or pulling a CB ? I suspect the number is exactly zero.

Therefore, as you say.... it was an "overstated media stunt". We all know how the media like a good aviation story they can hype up... and what better than an aviation security story for the journos to have a field day on !

Both regulators and the manufacturers looked at his claims and found no issues with aircraft systems.

For the love of...
 

:ugh::ugh::ugh:

The very idea that someone could "hack" the aircraft systems is so laughably ridiculous I really don't know why I'm bothering, but for the sake of my sanity... this is impossible in the context of the 777. The T7 was introduced into service in 1995, so you can be sure the computer systems on the aircraft date back to technology from the late 80's at BEST. Most of the worlds so-called hackers weren't even BORN then, let alone have any experience working with a system from this era. This is a proprietary architecture, with no open "network ports" or wireless links or anything accessible. Please stop this rubbish. The Teso guy repeatedly mentioned here, did NOT hack an aircraft - he hacked a PC-based ACARS rehost. So he hacked a PC....

On another oft repeated mis-information, R-R did NOT receive any engine data after the ACARS system was deselected. The SATCOM system continued to receive SATCOM pings.... oh, I give up -> READ THIS:

TMF Associates MSS blog » Understanding ?satellite pings??

ELT's in doors
 

By being "in the doors" read: affixed to the inflatable slides which double for rafts in the case of an on water landing.

Dear POSTERS THAT INSIST ON POSTING THE SAME RUBBISH OVER AND OVER.... like this Keith Ledgerwood blah, blah, blah... please STOP IT. Learn to use the *search* function. It isn't hard and will avoid mindless repetition and save my blood from boiling.