A couple of years use, of multiple units of a similar model, in multiple
aircraft, by multiple users, in actual operating conditions, makes for a
strong argument of compatibility. Not conclusive, and it doesn't establish
any safety margins, but still a strong argument. Apple owes somebody a
complimentary box of grapefruit.

 

I wonder how long it takes for a Marine helicopter pilot to move from
skeptical and suspicious use, to acceptance, and finally to dependence?

 

 

Ed Price

El Cajon, CA

USA

 

 -----Original Message-----
From: Brian Oconnell [mailto:[email protected]] 
Sent: Monday, March 26, 2012 9:42 AM
To: [email protected]
Subject: Re: [PSES] New immunity testing by the FAA in the future?

 

There ARE problems with some devices, but the ipad may not be a problem.

 

USMC aviators have been using ipads in helicopters for almost two years
(that I know). In same squadrons' aircraft, there have been reports of
interference from other "external-use cockpit devices". Marine combat
aviation is a harsh environment, but the equipment has better support than
commercial aviation (you can work the techs unlimited hours and not incur
additional expense).

 

Brian

 

-----Original Message-----

From:  <mailto:[email protected]> [email protected]
<mailto:[mailto:[email protected]]> [mailto:[email protected]]On Behalf Of
Cortland Richmond

Sent: Sunday, March 25, 2012 4:51 AM

To:  <mailto:[email protected]> [email protected]

Subject: Re: [PSES] New immunity testing by the FAA in the future?

 

Hi, Derek (and group).

 

Many of us have over a long career had the chance to work on aircraft
systems (or others) for which immunity standards are imposed. In most cases
the signals emitted from properly functioning, non-intentional-emitter PED
do not ever reach the levels the subject equipment is required to tolerate.
IMO, it is in those cases still not proper to say PED operation should be
permitted during flight regimes.

There remain sensitive spectra be investigated; VHF communications, VHF and
UHF navigation and landing systems, IFF, DME/TACAN and TCAS systems and the
like.  There have actually been ASRS reports of PED's affecting flight
situation indicators and ILS flags, so for such victim devices, it seems we
do need to test to levels of emissions and likely at levels lower than those
permitted normally.

 

Intentional emitters are quite another matter -- see ED-118 re threat levels
-- and systems that react to them may never have been tested against the
particular threat one may pose.  While DO-160 threat levels are higher than
most of the PED's a person might bring aboard, most of the tests use a
nominal modulation only ASSUMED suitable for the purpose. I am now thinking
about the famous case of a GSM telephone which, being under 30 cm from a
victim (oven controller) device, turned on a gas broiler and almost caused a
fire. It does not help that those who make and sell aircraft systems have a
great deal of incentive to do only the minimum required testing, and a good
deal of disincentive to spend time going beyond that.  We simply have not
tested against all threats a passenger might carry, and this is another
thing missing from our analyses.

 

Some years ago I had occasion to test an automatic external defibrillator
for emissions in the aircraft VHF and UHF comm, navigation

and landing frequencies, IFF, TACAN/DME and TCAS ranges.   It appeared

at the time that none of the personnel at the firm I was then on contract to
(or at the test labs being used) had ever done such a test.

 

But it is OUR business to know the  test is needed -- and if possible, see
it gets done. I was writing the verification plan and was able to do so.

 

 

Cortland Richmond

 

 

On 3/24/2012 1356, Derek Walton wrote:

> HI All,

> 

> I've watched may people speculate about PED's and what they MAY do, so 

> I decided to go in the lab and make some measurements on my new iPad.

> 

> Obviously conducted is not an option, there's no power cord.

> 

> For radiated emissions to 1 GHz, the device is as quiet as a mouse. It 

> was only a quick look see, so I set it up as if I were reading a book:

> I have no movies loaded yet.

> 

> Clearly there are other options, so if any one would like to chip in 

> as to the way it should be running when tested let me know and I'll 

> run when I get a second and post results.

> 

> I'm thinking either playing a game with lots of video or a High 

> resolution movie.

> 

> Passive headset inserted also, cord unbundled.

> 

> Anything else?

> 

> Cheers,

> 

> Derek.

> L F Research

 


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