airmotive

....and everyone on FT moaned and whined that their electronics don't interfere with aircraft electronics, and it's nothing but power-crazed FA's colluding with cell phone companies and the Illuminati to keep passengers from playing Angry Birds....

Now that the electronics cat is finally out of the bag, today the FAA issued an AD, mandating the replacement of cockpit displays that are being interfered with by onboard electronics. (These are the latest/greatest displays, not old CRTs from the 1980s.)

"SUMMARY: We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, and Model 777 airplanes. This AD was prompted by testing reports on certain Honeywell phase 3 display units (DUs). These DUs exhibited susceptibility to radio frequency emissions in WiFi frequency bands at radiated power levels below the levels that the displays are required to tolerate for certification of WiFi system installations. The phase 3 DUs provide primary flight information including airspeed, altitude, pitch and roll
attitude, heading, and navigation information to the flightcrew. This AD requires replacing the existing phase 3 DUs with phase 1, phase 2, or phase 3A DUs, and for certain replacement DUs, installing new DU database software. We are issuing this AD to prevent loss of flight-critical information displayed to the flightcrew during a critical phase of flight, such as an approach or takeoff, which could result in loss of airplane control at an altitude insufficient for recovery, or controlled flight into terrain. "

FredAnderssen

I certainly haven't whined about it. I love it that Delta is keeping cellphones silent on their flights.

WillCAD

So, the replacement has nothing to do with possible interference from cellular phone or data signals, or from the laughable EMF from a non-transmitting device, or any other portable device at all - it is being done because they can be interfered with by on-board Wi-Fi installations.

So, what's you point again?

airmotive

The point was that most folks on FT (and elsewhere) stated that they knew for a fact that electronic can, in no way, interfere with any aircraft systems.

ffsim

From your OP (emphasis added):

The fact that the airline installed electronics that interfere with cockpit instruments has nothing to do with the gist of your OP. Personal electronic devices are in no way a danger to commercial aircraft, as we're thankfully starting to understand and accept.

TheRoadie

The details of the issue show that the interference was a ground based test using signals in the WiFi frequencies. Not using specific WiFi enabled devices themselves. Not the on-board WiFi systems. No in-flight display blanking incidents have been observed. Display version 3A has better shielding and software and have been installed since 2012.

One proposal was to prohibit the cockpit crew's use of WiFi enabled devices like tablets only.

The FAA seems to be operating like the TSA - out of an abundance of caution....not because there's a direct cause->effect between a passenger's devices or the on-board WiFi antennas.

WilcoRoger

At the same time on the other side of the pond:

"Airlines can also allow the use of portable electronic devices (PEDs) throughout the flight, after a safety assessment process. As a result, passengers will be able to use their PEDs just like in any other mode of transport: throughout the trip.

The new guidance allows airlines to permit PEDs to stay switched on, without the need to be in ‘Airplane Mode’. This is the latest regulatory step towards enabling the ability to offer ‘gate-to-gate’ telecommunication or WiFi services."

https://www.easa.europa.eu/newsroom-...oughout-flight

pa3lsvt

Note where the FAA summary points out that the displays fail to meet the minimum requirements for robustness against WiFi signals. There will be a factor of safety built in to the minimum requirement, meaning that the minimum requirement is a multiple of real-world expectations for actual exposure.

In other words, the displays do not meet the specifications for installation of WiFi systems. NOT that they have been demonstrated to malfunction when used with typical, normal WiFi emissions from portable electronics.

NOT that there has been an instance of loss of the instrumentation during a critical phase of flight.

So, your data (FAA summary quoted) does not match your conclusion (WiFi can bring a plane down during flight). But, go ahead and keep your tablet or cell phone off below FL10 if it makes you feel safer.

airmotive

Really, that was my conclusion? Hmmm....let me reread my post.
Nope. Nothing about bringing down airplanes. Sorry.

Look...the standard that was used to forbid use of electronics on flights was this: Each model of electronic device that could be used (thousands? Millions?), needed to be tested at every location on an aircraft where it could be used (thousands?), and repeated for every model and variant of aircraft in service (thousands?).
Obviously, after doing the math, that was a completely impractical standard to meet.

However, that was the standard. Period.

Unlike in many other fields, commercial aviation has a standard that is either met, or it is not. There is no "but we really, REALLY want this, so the standards don't matter".

Either meet the standard, or change the standard.

But, you can't just change the standard without evidence supporting the standard can be changed without adversely affecting risk.

What has happened is, over time, sufficient evidence was accumulated that all additional risk associated with electronics used did not raise the cumulative risk above an acceptable level. The math worked in favor of permitting electronic devices.

Risk assessment....It's all about the math.

However, those folks who insist that there's no such thing as interference, and it's all about control and conspiracy...the facts don't support your argument.

WillCAD

The risk has always been largely theoretical. The numbers never supported the conclusion that PEDs posed any genuine danger to commercial aircraft avionics. The number, in this case, being a big fat gooseegg - ZERO reported cases of a commercial aircraft having trouble with avionics in flight, attributed to PED use on board. Despite the millions of PEDs being used on board commercial aircraft every single day, in every aircraft in flight, all over the world.

Any who mentioned "control and conspiracy" are the nutjob fringe. Those of us with common sense realize exactly from whence this prohibition came - from blind, ignorant, mindless panic. Because in the modern technological society, electronic devices are the new voodoo. Look out! He has a magical talisman that works on the Electric Magic! The plane works on the Electric Magic! What it the two Magics don't like each other?! They might smite us!

Never attribute to malice that which can as easily be attributed to stupidity.

The "proof" standard you mentioned was a hyperbolic overreaction to a threat that was largely theoretical. It was never necessary to test every possible combination of every possible PED on every possible variant of every aircraft in flight, any more than it is necessary to test a boat on every possible body of water on the planet before you can certify that it's water tight.

But the testing has been done - by passengers. Every possible combination of PEDs in every position within the every possible aircraft HAVE been used, by people too stubborn to turn them off but smarter than Alec Baldwin, over he last twenty years. So far, not one failure of commercial avionics has been attributed to these devices.

And just to reiterate - The monitors in question were replaced because they failed to meet a minimum guideline for playing nicely with ANOTHER AIRCRAFT-INSTALLED SYSTEM, the wi-fi router. Not PEDs.

One piece of the plane might not play perfectly with another piece of the plane. So they upgraded it. Just like they have to upgrade wiring to handle increased power demands when new systems are installed, just like they have to upgrade onboard software when engines are upgraded or winglets are installed, so too do they have to upgrade individual components when they install a new component elsewhere in the craft.