Monthly Archive: October 2017

Quiet aircraft? NASA’s on the job, but when?

By David Sykes, Vice Chair, The Quiet Coalition

Hope is nice now and then—don’t expect results tomorrow, but maybe next year?

If you like an occasional look ahead—toward a world with quieter aircraft—read the August 14-September 3 issue of Aviation Week.* In an article entitled “Sound Barrier: Noise is emerging as the biggest challenge to high-density urban air-taxi operations,” the magazine’s managing editor for technology, Graham Warwick writes about what NASA (and yes, Uber) are doing to build a future of inter-urban transport. Are you ready to imagine “Air-Uber”?

The key is convincing municipal governments that these air-taxis will be quiet(er) than conventional aircraft. So note the term “eVTOL” (Electric Vertical Take Off and Landing craft, or distributed electric-propulsion vehicles). That’s right, they’re electric. This is the likely future of quieter, low-emission air transport—and as the video above proves, it’s no joke.

Do we really need eVTOL air-taxis? That depends on what “we” means. At any rate, it turns out the kink in this scenario is the noise problem: so switching to quiet eVTOLs is a prerequisite to getting this air-taxi fleet off the ground in urban areas. Hence, NASA has taken on the noise issue—at last! (NOT the FAA—which is a good thing overall since FAA has steadfastly resisted doing anything at all about noise for decades).

Meanwhile back in the real world, why can’t American airports and airlines simply encourage adoption of the new Pratt & Whitney quiet jet engine that is already in use in the UK and EU (the PW1100G geared turbofan). It’s supposed to be 75% quieter and 15% to 20% more fuel-efficient than conventional jet engines. Furthermore, Airbus has already installed the Pratt & Whitney engine on it’s new A320neo aircraft and 90 of them have already been delivered to 11 airlines (only two of which are American: Spirit and Frontier). Another issue of Aviation Week* reported favorably on the launch of this new, quieter aircraft and cited one source as saying “[t]he A320neo is now the quietest aircraft.”

There are plenty of Airbus planes in the fleets of US-based airlines, so let’s urge airlines to order a few more and retire their noisy fleets of aging aircraft! Airbus is set to deliver 200 more of them this year.

Sadly, the FAA is not going to get out in front of the noise issue anytime soon. They continue to insist that while noise may be “annoying” to some people, they won’t let that get in the way of the roll-out of their NextGen program—despite the fact that NextGen is precisely the program that has so enraged the three dozen members of Congress who formed the Congressional Quiet Skies Caucus and the 36 communities across the USA that have formed the National Quiet Skies Coalition.

Take a look at this recent presentation given by the FAA to the Congressional Quiet Skies Caucus: FAA Powerpoint PDF.

Doesn’t sound like they’re in any rush to quiet down America’s airports, does it? So I’m betting on NASA’s approach, i.e., electrically powered aircraft and “alternative solutions”—such as convincing airlines to stock their fleets with Airbus planes. Maybe the competition will finally wake up Boeing and GE and they’ll realize that some of us understand that noise is much more than “annoyance,” it’s a public health issue.

*Sorry, you’ll either have to subscribe to Aviation Week online or read it in the library.

In addition to serving as vice chair of the The Quiet Coalition, David Sykes chairs several professional organizations in acoustical science: The Acoustics Research Council, American National Standards Institute Committee S12, Workgroup 44, The Rothschild Foundation Task Force on Acoustics, and the FGI Acoustics Working Group—a partner of the American Hospital Association. He is the lead author of “Sound & Vibration 2.0 (2012, Springer-Verlag), a contributor to the National Academy of Engineering report “Technology for a Quieter America,” and to the US-GSA guidance “Sound Matters”, and co-founded the Laboratory for Advanced Research in Acoustics (LARA) at Rensselaer Polytechnic Institute. He recently retired from the board of directors of the American Tinnitus Association. A graduate of the University of California/Berkeley with graduate degrees from Cornell University, he is a frequent organizer of and speaker at professional conferences in the U.S., Europe, Asia, and the Middle East.

Noise can make you deaf

Photo credit: UrbanUrban_ru licensed under CC BY-SA 2.0

And the Hindustan Times, knowing this, advises its readers: This Diwali, turn a deaf ear to noise.

Diwali is happening now, so enjoy the sigts–and some of the sounds–and don’t forget to pack some disposable earplugs for yourself, your friends, and family.

Where is the quietest place on earth?


Not this one, but close | Photo credit: Max Alexander / PromoMadrid licensed under CC BY-SA 2.0

A room within Orfield Laboratories Inc. in south Minneapolis, according to Steve Orfield, 69, the lab’s longtime owner. Jenna Ross, Star Tribune, writes about the silence in the anechoic chamber at Orfiled Laboratories and how the silence gives way to the sounds of our bodies, leading visitors to “suddenly hear their blood flow, their inner ears buzz, their artificial heart valves click.”

Orfield’s chamber was originally used to help companies understand “how people experience the look and sound of their products,” but now it has a higher and better use: seeing how the room “might help people with post-traumatic stress disorder, autism and other hypersensitivities.”

Click the link above to read this fascinating article.


How quiet should it be?

Lake Verynwy, Wales, Oct. 2017 | Photo credit: Dr. Daniel Fink

by Daniel Fink, MD, Chair, The Quiet Coalition

I recently wrote about measuring sound on an alpine hike, noting that the reading of the ambient noise level, which was in the low 40 decibels, was much quieter than we hear in our urbanized settings. I also noted that noise exposure, as part of the total daily noise dose, is what causes noise-induced hearing loss.

Another important adverse effect of noise–especially nighttime noise–is disruption of human activities, including sleep disruption. A measure of the noise impact on sleep is called the LDN, How quiet is it in a non-urban setting?

I hadn’t thought about this until last night. My wife and I are traveling in a remote part of Wales, staying at a hotel overlooking Lake Vyrnwy, a manmade reservoir supplying water to Liverpool 75 miles away. It took more than an hour of driving on one-lane country roads to get here. (It wasn’t that far, but at 25 mph, it took a while.) I woke up at night and realized how quiet it was: no sirens, no cars, no airplanes, no helicopters, no horn-based alerts when the neighbor’s son comes home from partying at 2 a.m. Curious, I fired up my Faber Sound Meter 4 app on my phone and measured the ambient noise at 33.7 C-weighted decibels. It was so quiet that the sound meter said there wasn’t enough data to report an A-weighted measurement. (I don’t understand the technical details of why this wouldn’t work.) Unweighted decibels measured 35.4.

Why is this important? Sleep disruption causes a stress response, a neuroendocrine response with increases in stress hormones and a parasympathetic nervous system response, with increased blood pressure and pulse. These involuntary physiological responses are what cause the increased morbidity and mortality reported from transportation noise exposure (and are discussed by Hammer, et al., and Basner, et al.). Yes, the experts think the evidence is strong enough to support a statement of causality, not just a statistical association or correlation. Even sounds as low as 32-35 decibels can disrupt sleep, causing microarousals as measured by EEG monitoring.

And now I know the answer to my question.  How quiet should it be? At night the natural sound level should be under 40 decibels, probably under 35 decibels, and not urban nighttime noise levels of 55 to 65 decibels.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He serves on the board of the American Tinnitus Association, is the interim chair of Quiet Communities’s Health Advisory Council, and is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.

Proof quiet motorcycles are possible

They exist, and the police department in Warrensburg, Missouri is looking to purchase them.

If the motorcycles are powerful enough for the police to consider using them, then surely they are powerful enough for someone who just wants a reliable means of transportation. Among other things, “the bikes can go up to 140 miles in the city before being recharged,” though a full recharge takes nine hours.

Naturally, the motorcycle isn’t absolutely quiet, but removing engine noise is significant. Said Police Chief Rich Lockhart, “It’s a really, really cool bike. I rode it around quite a bit today and got a lot of looks from people. It’s completely silent. All you hear are the tires.”

For the sake of our ears, let’s hope Zero motorcycles and other all-electric competitors become the new normal.


Hearing loss a big problem for farmers and ranchers

by Daniel Fink, MD, Chair, The Quiet Coalition

This report discusses the problem of occupational hearing loss in farmers and ranchers. You may be confused, thinking farmers and ranchers must surely work in some of the most peaceful workplaces that exist. And that may be true part of the time, but they also use heavy equipment (tractors, harvesters, etc.) for long periods of time. Says Dr. Richard Kopke, M.D., FACS, chief executive officer of the Hough Ear Institute in Oklahoma City, “[e]xposure to tractors, forage harvesters, chain saws, combines, grain dryers, even squealing pigs and guns, can lead to significant hearing loss.”

Dr. Kopke offers advice to farmers and ranchers on how to avoid hearing loss, including the same point I always make: if you have to raise your voice to be heard, the ambient noise is above 75 A-weighted decibels and hearing loss is occurring.

But it’s not just farmers and ranchers at risk of noise-induced hearing loss. It’s everyone.

Hearing is precious. Speech is the main way humans communicate and relate to one another. As Helen Keller said (paraphrasing), “blindness separates people from things, but deafness separates people from people.”

It’s National Protect Your Hearing Month. Once hearing is lost, the only treatment is a hearing aid (or a cochlear implant for the severely impaired). If it sounds too loud, it IS too loud! Turn down the volume, leave or move away, or insert ear plugs or use ear muff hearing protection.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He serves on the board of the American Tinnitus Association, is the interim chair of Quiet Communities’s Health Advisory Council, and is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.

It’s about time

New Hampshire police plan to crack down on noisy motorcycles. WCVB reports that Portsmouth, New Hampshire police are getting serious about super loud motorcyles, and they will be “investing in equipment and training needed to recognize if a motorcycle is illegally loud.”  What’s the standard for illegally loud?  Apparently in New Hampshire it’s 92 decibels. We would suggest, however, that the standard should be 83 decibels, which was the noise level limit established by the EPA back when the agency was properly funded and not being attacked from all sides.

Still, whatever the applicable decibel level, at least the Portsmouth police are taking motorcycle noise seriously. How seriously? They plan to set up checkpoints to test motorcycle noise level. Let’s hope this is the start of a nationwide trend.