FAA paper Noise Attenuation Properties of Noise-Canceling Headsets

InFO

Information for Operators

U.S. Department InFO 07001

of Transportation DATE: 1/5/07

Federal Aviation Flight Standards Service

Administration Washington, DC

http://www.faa.gov/other_visit/aviat...ne_safety/info

An InFO contains valuable information for operators that
should help them meet certain administrative, regulatory, or
operational requirements with relatively low urgency or
impact on safety.

SUBJECT: Noise Attenuation Properties of Noise-Canceling
Headsets

Purpose: This InFO alerts operators, directors of operations
(DOs), chief pilots, and flight crewmembers who may be using
noise-canceling headsets of the potential for misdetection
of audible alarms and other environmental sounds.

Background: Ordinary (non-noise-canceling) headsets reduce
ambient noise levels through a physical means by providing
some acoustical quieting. Noise-canceling headsets cancel
noise through a combination of physical means and electronic
means. While this technology can have many beneficial
effects such as providing clearer communications, reduced
pilot fatigue, and added comfort, electronic attenuation of
important environmental sounds and alarms may occur.

Discussion: Noise-canceling headsets are most effective over
a narrow frequency range, but the specific frequencies may
vary by make and model. Also, these electronically
attenuated frequencies are often proprietary to the
manufacturer and may not be publicly available. Therefore,
it is difficult to assess any effects the headsets may have
on discerning environmental sounds such as:

.. Vital communications between flight crewmembers or flight
attendants, other than those attainable through interphone
operations;


.. Abnormal mechanical noises or abnormal engine sounds;


.. Audible alarms other than those discernible by electronic
means;


.. Vibrations or wind noises; or


.. Other aircraft during ground operations.

Recommended Action: Operators, DOs, chief pilots, and
crewmembers of aircraft should evaluate their use of
noise-canceling headsets. The FAA recommends sampling the
available manufactured makes and models when performing such
evaluations, since performance and attenuation properties
vary. Evaluations should be conducted while both on the
ground and in flight during normal operating conditions to
ascertain if any audible alarms or other environmental
sounds, or combinations thereof, can be detected while
electronic noise attenuation is on and active. If any
audible alarms or environmental sounds cannot be discerned,
operators should elect to find other solutions to discern
such alarms or sounds, or discontinue the use of
noise-canceling headsets.

Approved by: AFS-200

Jim,

Operators, DOs, chief pilots, and
crewmembers of aircraft should evaluate their use of
noise-canceling headsets.


Done that. It's a complete non-issue. I wish they were that good...

--
Thomas Borchert (EDDH)

Jim Macklin wrote:
InFO

Information for Operators

U.S. Department InFO 07001

of Transportation DATE: 1/5/07

Somebody wasted my tax dollars coming up with this piece
of "obvious" drivel? Try them on and see what you can
hear?

I need to get some FAA contracts going.

Somebody wasted my tax dollars coming up with this piece
of "obvious" drivel? Try them on and see what you can
hear?

Phhhhtttt. These guys are pikers, Ron. Hell, at least they're
studying something quasi-useful.

Here's a good one: There are "government studies" going on nationwide
-- to the tune of tens of millions of taxpayer dollars -- trying to
figure out why people are FAT, as if this is some sort of mystery.

Closer to (my) home, let's talk about the hundreds of thousands of
dollars spent on "environmental impact studies" for our runway
extension in Iowa City. As if any one of us couldn't have written a
fact-filled report on any given weekend, describing the effect of
adding 1000 feet of pavement to the end of the runway.

Or, perhaps, we should talk about the University of Iowa's "driving
simulator" that has cost millions, and generated little real science?
Or their ongoing millions in grants to develop "synthetic vision" --
when it's already for sale in ads in every aviation magazine.

The more you look, the sicker you become. It's best not to think about
it.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

wrote in message
ups.com...
Somebody wasted my tax dollars coming up with this piece
of "obvious" drivel? Try them on and see what you can
hear?

Phhhhtttt. These guys are pikers, Ron. Hell, at least they're
studying something quasi-useful.

Here's a good one: There are "government studies" going on nationwide
-- to the tune of tens of millions of taxpayer dollars -- trying to
figure out why people are FAT, as if this is some sort of mystery.

Closer to (my) home, let's talk about the hundreds of thousands of
dollars spent on "environmental impact studies" for our runway
extension in Iowa City. As if any one of us couldn't have written a
fact-filled report on any given weekend, describing the effect of
adding 1000 feet of pavement to the end of the runway.

Or, perhaps, we should talk about the University of Iowa's "driving
simulator" that has cost millions, and generated little real science?
Or their ongoing millions in grants to develop "synthetic vision" --
when it's already for sale in ads in every aviation magazine.

The more you look, the sicker you become. It's best not to think about
it.

Hey! They gotta **** away $2.7 TRILLION _somehow_. Gotta keep up the
hysterics about deficits, ya' know!

Buying off voters with illegal pork is a lot cheaper than bribing them with
your own money.

"Ron Natalie"
I need to get some FAA contracts going.

Ron,
Sell them something that I can buy that will filter out all the government
drival... something like ANR contact lenses. Of course that would
iniciate an AC advising us not to use them during flight...
Jim

I was reading it yesterday,,, I'm with you on this one; what a waste of tax
dollars! I printed out my copy to show to my fellow CFI's at my FBO -
we all had a chortle or two.

--
=-----
Good Flights!

Cecil E. Chapman
CFI-A, CP-ASEL-IA

Check out my personal flying adventures from my first flight to the
checkride AND the continuing adventures beyond!
Complete with pictures and text at: www.bayareapilot.com

"I fly because it releases my mind from the tyranny of petty things."
- Antoine de Saint-Exupery -

"We who fly, do so for the love of flying. We are alive in the air with
this miracle that lies in our hands and beneath our feet"
- Cecil Day Lewis -

Jim Macklin wrote:
InFO

SUBJECT: Noise Attenuation Properties of Noise-Canceling
Headsets

They are absolutely correct. It's about time someone exposed the myth!

Please send all working ANR headsets, along with a modest $10/set
disposal fee, to me for recycling.

Inoperative sets can be disposed of locally, as they pose no danger.

That is all, please comply...

Please send all working ANR headsets, along with a modest $10/set disposal fee, to me for recycling.

I've Emailed my headset to you. Could you send me a receipt for tax
purposes?

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

("Jose" wrote)
Please send all working ANR headsets, along with a modest $10/set
disposal fee, to me for recycling.

I've Emailed my headset to you. Could you send me a receipt for tax
purposes?


He won't get your e-mail if he's got ..."Active Noise Reduction" filters
enabled. g


Montblack