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Flightsimman
10th Oct 2008, 06:24
I was watching "Sunrise" on channel 7 (Australia) this morning and almost threw my bowl of cereal at the TV when I heard this "so-called" professional talk about how electronics were dangerous for aircraft systems (you have to listen to this explanation)!!

Yahoo! (http://cosmos.bcst.yahoo.com/up/player/popup/?rn=1341467&cl=10124488&src=y7lifestyle&ch=)

:}

bucket_and_spade
10th Oct 2008, 07:29
One - lose the comedy shirt. You look like a muppet.

Two - sweet Jesus, his "zero and one" spiel was painful to watch.

I need to go and take a cold shower and lie in a darkened room for a bit...

What's he got a PhD in!?

cockney steve
10th Oct 2008, 10:36
On the whole, I didn't think it was too bad!(the presentation, -but the shirt- :yuk: )


He WASN'T broadcasting to the PPRUNE INTELLIGENTSIA.....But The average OZ......and we all know about the hats with corks and billabong stew! :E

He reinforced the importance of keeping a belt fastened, and the "dramatised" reasons that phones, etc. should be switched off.
"nobody ever went wrong under estimating Joe Public's intelligence "

OTOH....As an intelligent? person, I'm asked to believe that a cheap, £50-£500 device, made to transmit and readily absorb EM radiation, can swamp a Faraday -cage, with cost-no-object, several million£ ,shielded,redundant,safety-criticality analysed wiring and electronics.
The bullcrap is there, OK.

EITHER the systems ARE properly designed and manufactured.....in which case they're impervious to a few crappy (in relative terms) radiating a bit of EMI.....OR They're LYING and selling an ILLUSION of quality.....necessitating the "cover your ass" move of blanket-bans on phones/computers.

As pointed out elsewhere on the forum- planes take lightning-strikes, fly through severe electrical storms and yet continue to function.

the sheeple are being led up the garden path again!

NZScion
10th Oct 2008, 10:54
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."

-- Albert Einstein

Locked door
10th Oct 2008, 12:46
Cockney Steve - Wrong

Speaking with 5000+ widebody hours and a BEng in electronics and digital communications.

The effects of RF on complex electronics is such a huge subject no one properly understands it. While individual components can be engineered to be immune the systems in a commercial arcraft are complex and effects are not possible to model. Additionally due to differences in manufacture each aircraft can be considered unique.

One simple effect is that a poor aluminum weld can rectify RF signals into DC currents creating magnetic fields, the result I think I've seen in the LHR TMA in a 747 when both VOR needles started spinning. Our cc subsequently identified a pax on the upper deck trying to call his wife. Similar effects can occur at individual component solder joints.

The easiest (and cheapest) way to prevent this from happening is to remove all unnecessary sources of RF radiation. The newer systems that allow use of mobile phones in the air mitigate these problems by operating with the phones at their lowest broadcast strengths whereas a mobile hunting for a signal will be broadcasting at max strength.

It will be interesting to see whether the QANTAS incident can be proved to be due to the effects of un unwanted RF broadcast inside the a/c but I suspect that as these incidents have so many parameters making them unique that the investigating authority will be unable to reproduce it.

Just my two pennies worth

LD

Troy McClure
10th Oct 2008, 12:47
What I've always wondered about - how come in the most critical phases of take-off and landing are the aeroplane systems not affected at all by flying near or even over mobile phone transmitter masts pushing out far higher radio waves than any mobile phone?

Besides, what proportion of flights are there without at least one mobile phone turned on somewhere in someone's bag or pocket? There's always a 'Welcome to XXX, calls will cost you yyy per minute' text messages coming through to the overhead bins in the final stages of approach of most international flights I've been on. And on several occasions, my phone, in my pocket, on the flight deck.

And why do petrol stations not burst into flames whenever someone locks their car with a remote central locking key fob as they head to the kiosk to pay?

And how do mobile phones work at all - surely their electronic circuits should by rendered useless by their own radio transmissions. Yet last time I looked, my phone was working fine, despite not being in 'flight mode'.

As for the Japanese tourist with a camera - there's a word for phenomena that can't be repeated experimentally: 'COINCIDENCE'.

bjornhall
10th Oct 2008, 17:36
One - lose the comedy shirt. You look like a muppet.

He is a muppet, and what he says is a comedy, so I think the shirt suits him just fine! :)

Flightsimman
11th Oct 2008, 07:41
LOL !!

Generally his pretty good but I think he must of been in the midst of a "Micro-Sleep" when he was giving his segment.

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