Flight 447: Detailed meteorological analysis

[Nesti]

I found this in my net-travels. A very informative write-up - I got a lot out of this.

As he concluded, the storm intensity suggests that a series of issues, perhaps each one insufficient to down the aircraft by itself, combined to form a catastrophic and unrecoverable situation. The 'dragons' that can drag down a jet.

http://wattsupwiththat.com/2009/06/03/air-france-flight-447-a-detailed-meteorological-analysis/

Once you've read the article, might I suggest that you read the post by [ adoucette (09:26:36)], this person has an extremely valid point. Although the suggestion is unlikely to have occured within the initial series of major events, it may prove to be the straw that broke the camel's back; high speed yaw inputs as a result of loss or erratic flight computer operation, resulting in a failure of the vertical stabiliser.

[Enchilada]

Sorry a wee bit insensitive here. More thinking of the families back in France and the pain in not knowing happened to their love ones. Wanton speculation doesn't comfort them either. :(
Please leave it to the experts and investigators conclusions before "jumping on the bandwagon" of the sick gutter-grabbing stories of the relentless media we are all subjected too! :mad2:

[saturn c]

i hope they find the black box.

[Nesti]

Enchilada; you are wrong. Nothing I wrote or cited was in any way inappropriate. "the sick gutter-grabbing stories of the relentless media" ?? Did you even bother to read the information at all ?? :screwy:

It's good to have an opinion, but why are you judging me - what gives you the right to call me a "wee bit insensitive" - who do you think you are?!

I've lost 4 friends in aircraft related incidents in the 11 years that I was a test flight engineer in the defence force, not including SAS and aircrew mates in the Black Hawk incident. I also conducted accident investigations during my time, I am an expert. I have pulled dead bodies out of crashed aircraft in Vanuatu and the Solomon Islands, have you done the same?? But it's okay for you to from an opinion on me though...right? The report I cited was very factual and worthy of some thought - it came from an expert in meteorology.

Wanting to know what's happening out in the world is a GOOD thing. Wanting to known the opinions of other is equally GOOD. I suggest you have a good look at yourself, before judging others and labeling people that you have zero knowledge of. At least I posted something worthy of discussion.

Also, I hope you posted that the 'David Carradine' thread was inappropriate also - or do you prefer to be hypocritical?

Or perhaps this is another one of those 'Clicky' forums?!

"Jen's Enslaved Devotee", more like 'frustrated' - you see, anyone can point the finger and draw conclusion without knowledge.

[saturn c]

:clap::clap::clap::clap::clap::clap ::clap::bowdown:couldnt agree more nesti. well put!

[Nesti]

And just for the record. My partner and I own and run a wellness centre. many of our patients have either been diagnosed or are dying of cancer. We are referred to by Oncology Departments regularly. We train people at our institute on how to do what we do.
http://www.stillpointwellness.com.au/

We also sponsor a Thai Orphanage just outside Bangkok (computers and software for child health tracking). So when an adopted baby in Germany for instance, has a health issue, it doesn't take 6mths to get a reply.

I have written a book which describes alternative therapies in lay science terms so that the average person can embrace these avenues. That's taken me 23 years of constant effort.

Enchilada; if you think I'm a "wee bit insensitive" of an person. What have you done for humanity sir?

[kinetic]

Mark,

A few questions a few of us were discussing at work yesterday about
telemetry such as the data that is recorded in-flight...cockpit voices, avionics etc:

Could it be real time transmitted via satellite to a receiving station?
This could help fill in a lot of the missing picture at least in the
minutes before the loss of signal.
Is that done already anyway to a degree by the airline HQ?
Would this data stream be far too high in bandwidth to be practical?
I'm assuming flight data for the shuttles, for example, is able to be studied this way
because of the almost nil prospect of FDR recovery in a re-entry catastrophe?

regards,

Steve

[Jeff]

Intelligent and fascinating analysis Mark ... thanks for posting. Hopefully root cause can eventually be isolated, understood, and leaned from.

[Nesti]

kinetic (Steve)

Great question Steve. Luckily, after my aviation career, I got into emergency data communications and sold solutions to fire, police, ambulance services etc. I might be able to answer it.

As per the article, it is true; we do not currently have enough bandwidth for trancieving information from and back to aircraft. Of course, there are tens of thousands of aircraft airborne at any one time and Black Boxes do record large quantities of data, not just pilot inputs, but health monitoring information as well.

I feel that the primary reason satellites are currently not capable of such loads is because we looked to other technologies years ago, such as underwater communications pipelines, which allowed us to grow in our communications exponentially, while the RF lagged due to technology hurdles.

Currently, one of the best systems for this type of data transmission is Spectrum (Direct-Sequence spread spectrum communications - I only know the very basics on how it works; it’s very complex and requires shuttling/hopping from one frequency within a band range to another at sequenced intervals). This allows for unprecedented signal security and protection of signal degradation and [artificially] increases bandwidth, but it’s very expensive and it is very specific. Spectrum is used for spacecraft communication to a great degree (especially during control activity and going to and from orbit).

To have world-wide coverage of a Spectrum type signal, would take at least another fleet of satellites equal in number, but more than likely greatly superior in performance than our current GPS network. It takes wars and conflicts to warrant that level of government spending (I’d rather go back to compass and maps).

My sole gripe in modern aviation is electronics, not navigation, communications etc, but Fly-by-wire. I’m a big fan of cables, wires, bell cranks, pulleys, push-pull tubes etc. I don’t like the idea of a computer telling a hydraulic system what it should be doing. Call me old fashioned, but I’ve worked of Iroquois and Black Hawks, and give me the robust Huey any day. The whole concept in safe flying is really, really simple; know your limitations and when in doubt take another path (direction, go-around, whatever the situation is).

I’ve read some articles in the past, which I just had to put down (too much lingo), but the basics are here, as well as lots of other cites;
http://en.wikipedia.org/wiki/Spread_spectrum

In short, the article hits the nail on the head; we cannot have wireless Black Boxes. Also; this was not an unusual storm for the region and time of year.

Funny enough, radio controlled planes and helicopters were the first to benefit from this signal (Called Spektrum), which allows up to 10 radios to be transmitting concurrently without any interference. It doesn’t work with carbon fibre between origin and receiver, the shadow corrupts the link.


Cheers
Mark

[MrB]

An interesting read Mark, thanks.
I have no idea what was so insensitive about your post :shrug:
DNFTT

[Enchilada]

I think you've misunderstood me here. I meant the story and not you at all. In the end, I think the story is idol speculation without evidence. Whatever happened, my point was just a moment for the loss of life. Nothing in the article you have really reflects that IMO. That is what I think.

[MrB]

Just to clarify a couple of things, Spread Spectrum has been in use for some time, for example the old CDMA mobile phones used a variant of it, wireless networking(WiFi) uses it.
I consider the RC world pretty slow on the uptake... infact, I got sick of waiting so started designing my own 2.4GHz transmitter modules(to suit Futaba Tx's) when Spektrum(brand) in collaberation with JR released their stuff... I gave up on mine, cheaper and quicker to buy someone elses!
Spektrum is not really spread spectrum, once binding has been done, they are tied to that channel... atleast that was the case in the beginning.... not so sure about the newer Spektrum radios.
Futaba and Hitec do use Spread Spectrum (FASST and AFHSS respectively)
The 2.4GHz ISM band (Industrial, Scientific, Medical) has 13 channels available, with TDM (Time Domain Multiplexing) there can be hundreds of 'pseudo-channels', I recall reading about some huge meeting in the US years ago where the organisers decided to crash test the emerging 2.4Ghz systems by asking all that attended to turn their transmitter on at the same time(all aircraft grounded)... don't remember the exact figure but there was something like 100 transmitters and receivers all on at the same time and not a single case of interference was reported.
While designing my system, I decided that interference(as in erratic behavior) was impossible.
Loss of signal could happen(would be almost impossible), forcing receivers into failsafe mode, but interference as modelers think of it(someone else controling their model) is just not possible. I'd explain why, but it would blow this post out to 10,000+ words.. haha.
The MAAA in its infinite wisdom set the 10 transmitter limit.
Anyway, enough of that from me ;)

I believe the wireless black box system possible, it will take lots of money and time, but it can be done, the technology is there, there are large swathes of the radio spectrum that are not being used so the bandwidth is there.
Just have to get the ball rolling, most airlines around the world initially resisted the introduction of the black box. It was only after it became mandatory that anything happened at all.

[Nesti]

CDMA?? No kidding - Wireless doesn't surprise though.

But if wireless is a type of Spread Spectrum, why the need for encryption...is it because the sequence is carried within the protocol and thus open?

Interesting notion to consider, isn't it?!

[MrB]

Never really delved into the 802.11 protocol, but it uses DSSS, Direct-Sequence Spread-Spectrum, so yeah, the sequence is a know.

CDMA by the way, stands for Code Division Multiple Access.... basically it means that, for example, 10 mobile phones could at the same time be on one frequency, but with no interference. Each of the 10 mobiles receives all 4.5 conversations(huh? think about it ;)), but each packet of data, that each phone receives is preceded by an identifier, so the phones would just ignore the other 9 packets of data because the identifiers don't match the one it is looking for.
A nice way for the telco's to get thousands of phone calls onto a limited number of channels in the band... sound familiar?

[PeterM]

Hi Mark,
I found the link very interesting. Thanks for posting it. I see/took nothing in your post or the link as insensitive at all. Don't worry IIS is not clicky, just a good healthy range of opinions and a valuable resource. I'm sure you will enjoy the site very much, by the way welcome.
PeterM.

[Nesti]

L-O-L I don't need to think about it at all...Geez!

Was analog carried by CDMA? If so, remember when you could hear other conversations, but couldn't talk to them?

[Nesti]

Cheers MrB & PeterM

Have a nice weekend.

[MrB]

Not sure what the old analog system used, but yeah I do remember that happening.
Funnily enough, the CDMA phones used both systems, If you were out in fringe area's(usually country towns) the phone would switch to analog system.
Used to show on the phones screen as either a letter 'D' or 'A'.

LOL sorry, 4.5 just looked odd when I typed it :D

[GrahamL]

Hi Mark great read .. aside one trip up in a cessna a few years back .. I've never been off the ground in almost 50 years .

I do recall some pilots comments I've come across about fly by wire
that the removal of being able to feel how an aircraft is flying by the touch of a hand isn't a good thing.?

[Dennis]

I once did a 5 day aircraft safety course where some air crash investigators presented case studies. Those guys were a real bunch of sober, professional, smart and dedicated people wholly committed to discovering the cause(s) of accidents to prevent further recurrence.

I didn’t envy them their jobs, going in when there were still deceased people on the ground. I was astonished at their intensity, the length and intricacy of some investigations and how they sifted through everything, absolutely everything, in order to build a probable scenario of what contributed to the accident.

Cheers

Dennis

[Nesti]

Holy smoly!!!

Nightstalker, you just hit me with a sledgehammer. You're absolutely right. In the old style, we use 'force gradients' to simulate increasing feedback as the range from centre increases. This was because the hydraulic system was so sensitive. But a strong enough force on flight controls can still give true feedback. So that was fine and gave nice feedback while still having full hydraulic assistance. However, fly-by-wire used simulated feedback, similar to a game controller on a Sony Playstation. Even a stall-shake is simulated. The feedback is derived from the flight computer information. If the flight computer has corrupted information (as with AF447), the feedback may well be out of proportion, or worse yet, opposite. The enunciated alerts are also derived from the same system. Flying VFR, aircrew would be prone to vertigo and misinformation, if not impossible.

At a critical time a pilot needs all the physical feedback he can get, not corrupted and negative feedback.

Airbus would already know this, but damn Nightstalker, you're a genius!

Do you guys see how serious this issue would be?

[Nesti]

I couldn't do it as a career. Although satisfying, you're right, it would be a tough caper.

[leinad]

An interesting analytical read, thanks Mark.
Let's hope they recover the BB, to find further answers to the tragedy.