RE: [sc] more info on safety and cell phones on airplanes



RE: [sc] more info on safety and cell phones on airplanes

From: Pekka Pihlajasaari <pekka_at_xxxxxx>
Date: Sun, 12 Jun 2011 17:54:07 +0200
Message-ID: <89ACCC513C63C04E92840FEFC80D977C31E69E@xxxxxx>
The report is perhaps more telling in what it does not cover. As section
6.2 indicates, the hazards identified would apply to flight crew members
using mobile phones. A passenger would need to be quite resourceful to
gain access to within 30 cm of any part of the navigation or
communications equipment on a typical airliner.

An related FAA report "In-Flight Radio Frequency Spectrum Measurements
of Commercial Aircraft Cabins" (DOT/FAA/AR-06/41) from 2006 that
references the CAA study indicates that on at least 5 of 31 monitored
flights passengers successfully made calls with their handsets. Other
calls may not have been detected due to instrument limitations.

In the summary, the report suggests that airlines should carefully
consider review interference before the introduction of pico-cells into
their aircraft.

The lack of confirmation in the incidents reported in the IATA, does not
mean they were not caused by phones, just that the 

The scare quote that sensitive equipment is 'hidden' in the passenger
compartment sounds gratuitous. Aircraft design engineers, Boeing
included, seem unlikely to hide things where passengers can reach them.
Yes, the avionics bay can be considered to part of the pressurised hull
compartment, but it is hardly hidden, and definitely placed in a
location where it can expect the least amount of interference from
external sources. Further, any antennae used by the navigation
instruments will be outside the hull to avoid being shielded and
consequently away from the passenger generated radiation.

Without minimising the potential safety risk to flight, it seems that
the tone of the reports has changed as the technical and commercial
feasibility of pico-cell controlled networks in aircraft has improved. 

Not all safety concerns are critical!

Regards,
Pekka Pihlajasaari
--
pekka@xxxxxx 	Data Abstraction (Pty) Ltd	+27 11 484 9664
--
As recorded on the worksheets reproduced in Annex 1, the following
anomalies were
seen at interference levels above 30 volts/metre, a level that can be
produced by a
cellphone operating at maximum power and located 30cms from the victim
equipment or its wiring harness.

-----Original Message-----
From: safety-critical-request@xxxxxx
[mailto:safety-critical-request@xxxxxx] On Behalf Of
drdpj@xxxxxx
Sent: 11 June 2011 00:01
To: safety-critical@xxxxxx; safety-critical@xxxxxx
Subject: RE: [sc] more info on safety and cell phones on airplanes

Nice report. They found interference for the "worst case" cell phones
circa
2002. And as power requirements and capabilities for cell phones change,
and as we add new cellular systems and frequencies, this will need to be
continuously updated.  For example, the currently proposed 4G/LTE
network
for the US uses frequencies that lie right next to the GPS frequencies.
On
the other hand, the desire to increase battery life might result in
phones
that use less powerful broadcast power.

I would note that the result of the interference was loss of safety
margin,
not elimination of safety margin. Worst case impact at most Major, not
Catastrophic or Hazardous.  Thank goodness for small favors...

--Daniel Johnson

Original Message:
-----------------
From: SPRIGGS, John J John.SPRIGGS@xxxxxx
Date: Fri, 10 Jun 2011 10:31:21 +0100
To: safety-critical@xxxxxx
Subject: RE: [sc] more info on safety and cell phones on airplanes

You may be interested on this report, published by the UK CAA in 2003,
"Effects of Interference from Cellular Telephones on Aircraft Avionic
Equipment".
http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode
=detail&id=751 

I understand that the current electromagnetic susceptibility
requirements in the latest version of RTCA/DO-160 and EUROCAE ED14 are
more stringent than they were at the time the subject aircraft were
developed...

John

-----Original Message-----
From: safety-critical-request@xxxxxx
[mailto:safety-critical-request@xxxxxx] On Behalf Of Robert
Schaefer
Sent: 09 June 2011 18:49
To: safety-critical@xxxxxx
Subject: [sc] more info on safety and cell phones on airplanes

see:
 
http://abcnews.go.com/Blotter/safe-cellphone-plane/story?id=13791569&pag
e=2

  "Dave Carson of Boeing, the co-chair of a federal advisory committee
that investigated the problem of electronic interference from portable
devices, says that PEDs radiate signals that can hit and disrupt highly
sensitive electronic sensors hidden in the plane's passenger area,
including those for an instrument landing system used in bad weather."
Received on Sun 12 Jun 2011 - 16:54:24 BST