Malaysia Airlines Flight Goes Missing En Route to China - Flight MH370

[longpig_yum]

Just did a little exercise regarding online streaming of black box data.
Lets say the black box collect 100 data points every second.
I used 8 digit numerals with a decimal point eg: 123456.78

Every second the data would be 1000 bytes ( 1K)
Every minute the data would be 60060 bytes (60K)
Every hour the data would be 3603660 bytes (3.6 MB)

Now if I compress this data I get :
Every second the data would be 43 bytes
Every minute the data would be 272 bytes
Every hour the data would be 13129 bytes (13k)

4000 data points will compress to 288K an hour

This compressed data is so small I see no excuse for bandwidth to live stream
as much data as you want.

[Speed Daemon]

Re: Black Box exercise

I think you're oversimplifying the issue, and forgetting a few things. First of all you can't just throw bits into the air and expect them to arrive at the other end as if by magic. Frequencies would need to be assigned, modulation methods would need to be developed or selected, a system to organize the transmissions so that one plane doesn't talk over another must be devised. I don't think you quite realize what a huge administrative task that is!

You can forget about using existing radio channels; they're already spoken for. Airinc isn't going to give up its VHF ACARS frequencies without a fight. So while VDL Mode 4 does provide the technological foundation for downloading FDR data in real time from multiple aircraft, it has to sacrifice other services that the airlines and GA pilots will fight hard to keep.

Since VHF is line-of-sight, it's not the answer for areas not served by VHF air band, such as over oceans. HF radio isn't reliable enough and INMARSAT costs big money. Who's going to pay for it?

I also note that you're counting on data compression ratios in excess of 10:1, which simply isn't realistic unless you're using lossy compression. And while lossy compression is OK for photos and TV, it's a big problem for crash forensics. Let's say that a plane does crash, and they go to the ground-based FDR records and find out that due to lossy compression, "123456.78" is now just "1(something)". Not very useful is it? You've been thinking bit rate reduction when you should have been thinking of error detection and correction! That means more bits, not less.

Oh, and by the way, you forgot about the CVR data altogether.

The bottom line is that air safety is an important issue, but it requires diplomacy between nations, technological advancement, and most of all money. The cold hard fact is that the world has endless money to devote to delivering insane data rates to smart phones for personal entertainment, but almost none for disaster preparedness. That's just the fact of it.

[bhavlobhuro]

A question - is it possible for a passenger (or passengers) to use an electrical device to take over the aircraft or to assist them disabling the aircraft ACARS, transponder, or computers etc? Remember there were at least 20 persons on board from an electronic specialist company.

Another question - when you pass through airport security and your hand luggage is x-rayd are the images recorded and possibly kept (if yes for how long?). If so might be worth going through this data. I appreciate if covers a lot flights and not just MH370 but might be helpful.

Any comments

Hijackers didn't enter in the plane by routine, pass through securities and x-rays and immigration etc., they reach inside plane before plane arrived at the gate to take regular passengers and these people get inside with help of ground staff as in plane 55 passenger seats were empty.

[iazoniccc]

If you're referring to the German man who "created an app" that some believe can take control of an aircraft, his app only works in the virtual world of online gaming. Even he admits that it's a simulation. It cannot seize control away from the flight crew even on fly-by-wire aircraft. And the 777 is not fly-by-wire, so it's even more impossible.

It is possible that someone on board the flight who is an aircraft service technician (or knows one) could carry on service equipment (most likely a laptop) that could interface with the plane's internal computer network, and with the right passwords (the 777 uses the UNIX operating system) log in and change settings. This would require the cooperation (voluntary or coerced) of the flight crew of course. Nobody could take control of the plane while sitting back in the passenger compartment.



First of all, not all X-ray machines use digital processing. For the ones that do, it's not at all clear if they even have the capability of storing what's displayed on the screen as digital images. Even if they did there's no way to correlate the X-ray images with a particular passenger or flight. Right now none of that would help find the plane, which is the top priority.

Is there something in particular that you think they should be looking for?

I think you'll find the 777-200ER is fly-by-wire.

[whatsgoingonhere]

Or if they even saw it! If it flew over their territory and they didn't, it points to serious limitations in terms of their defence. I can imagine why some states might not want to co-operate with their near neighbours by revealing radar limitations.

Exactly - no-ones going to give up that information in a hurry, no matter what!

If we're going with the hijack theory....then the next question is who and why; and what or who is on board the plane? If this is the case my bet is the authorities already know this info. I like the idea of "the great plane robbery" and everyone on board is still alive

I have my suspicions about it being in the Indian Ocean way down yonder somewhere.... if they think it is somewhere there in the huge amount of ocean; then why is there only one plane searching the area? I think they've sent us all on a wild goose chase!

[Speed Daemon]

I think you'll find the 777-200ER is fly-by-wire.

You are correct, it is fly-by-wire. However the Boeing fly-by-wire system is easily defeated from the cockpit, and the plane can be hand-flown if necessary. The Boeing method is radically different from the Airbus method, which is more to my point.

What I should have said is "It cannot seize control away from the flight crew even on Airbus fly-by wire aircraft. And the 777 is not Airbus, so it's even more impossible." That was what meant, but got lazy about saying it.

Thanks for the correction!

[zed]

I suppose really the 2 most likely possibilities are pilot suicide or pilot stealing the plane and landing it somewhere.. strange though, if it was suicide and the pilot deliberately crashed the plane, why did he go to such lengths to avoid detection and why did he fly the plane for 8+ hours? Just get it over and done with? Perhaps he was waiting for the plane to run out of fuel rather than deliberately flying the plane into the ocean? The second possibility, the plane has landed somewhere seems so far-fetched, almost like something out of a James Bond movie. And what has he done with 250 odd passengers??

[Jackflash]

A thought has occurred to me, maybe the reason the plane was flown to a higher altitude was to suffocate all on board by turning off the engines and gliding for a while, I think the air inside the plane is pressurized by bleeding air from the engines.

[Exadios]

A thought has occurred to me, maybe the reason the plane was flown to a higher altitude was to suffocate all on board by turning off the engines and gliding for a while, I think the air inside the plane is pressurized by bleeding air from the engines.

It is not necessary to go to a higher altitude in order to depressurize the aircraft. Just switch the thing to manual.

I interpret the increase in altitude as an indicator that the aircraft was out of control. Why I do not know.

[zed]

I interpret the increase in altitude as an indicator that the aircraft was out of control. Why I do not know.

Possibly. Or there was a struggle for control of the aircraft? Is there any logic behind the aircraft climbing to avoid radar detection?

[jermman]

But if there was a struggle, absolutely no signal of distress? Even if some hijackers knew how the transponders, distress signals, etc. worked...surely there would have been a moment for the crew to send out some signal of distress.

[Exadios]

Possibly. Or there was a struggle for control of the aircraft? Is there any logic behind the aircraft climbing to avoid radar detection?

A struggle for control would be included in the out of control state. Plainly the altitude hold function of the autopilot was off.

[Speed Daemon]

I suppose really the 2 most likely possibilities are pilot suicide or pilot stealing the plane and landing it somewhere.. strange though, if it was suicide and the pilot deliberately crashed the plane, why did he go to such lengths to avoid detection and why did he fly the plane for 8+ hours? Just get it over and done with? Perhaps he was waiting for the plane to run out of fuel rather than deliberately flying the plane into the ocean?

The thing is that there are two pilots...and a cabin crew...and passengers. While it's possible for one pilot to crash the plane quickly when the other one is in the lavatory, it's quite a different thing to try to lock the second pilot out of the cockpit and think that he'll just sit there and do nothing for all those hours. IMO it's far more believable that someone took command of the plane by force or threat of force than to think that hundreds of people also waited to die for 8 hours. That both pilots coincidentally became suicidal at the same time is even more improbable. That means that someone outside the cockpit must have known something was wrong long before the flight ended.

The second possibility, the plane has landed somewhere seems so far-fetched, almost like something out of a James Bond movie. And what has he done with 250 odd passengers??

The optimistic answer is that the innocent crew and/or passengers are stuck far from civilization, waiting to be rescued. The pessimistic answer is that the plan went awry, and the wreckage of the plane was swallowed up by a jungle somewhere.

Hijacking a spaceship is James Bond. Hijacking an airplane is fairly common. Here in the US it became almost commonplace for people to hijack planes to Cuba in the 1960s. There were a fair number of hijackings from Cuba to the US as well. Increased security has made it harder, but far from impossible.

[Exadios]

But if there was a struggle, absolutely no signal of distress? Even if some hijackers knew how the transponders, distress signals, etc. worked...surely there would have been a moment for the crew to send out some signal of distress.

As I understand it the change in altitude occurred after the transponder was turned off. Most of the distress signals, other than voice over VHF, are transmitted via the transponder.

The height gain information come only from the military radar track - not from the ADS-B or Mode S.

[Speed Daemon]

Is there any logic behind the aircraft climbing to avoid radar detection?

No. Back when the Concorde and were flying at altitudes up to 60,000' and 85,000 feet respectively, civilian air traffic control radar tracked those planes in commercial airspace.

Chances are that the report of going to 45,000' is as fallacious as many of the other false reports about this flight. I wouldn't read anything into it at this point.