Does any body know what the Db noise level of small, medium or maximum turbines is ?

Are they up to the big gas engines. 5 to 15 hp ?

The 1 I saw in the early days was about like a 1.20+ but the sound was more pleasent.

Hoss? Turbines quit? Maybe differences in everyone’s perception is part of the problem. Back in the day, I was a Red Baron too – and a member of Northwest R/C – and another R/C club that I don’t remember the name of (but you were there) so I’ve been around long enough to remember unmuffled engines and I have some piped engines but don’t fly R/C with them. I have not seem a turbine fly yet but one the AMA DVD, they seem pretty loud!

When we start referring to gearbox and prop noise as being loud in electric planes, maybe we’re paranoid enough to be our own worst enemies. I don't have an electric, but at our field they are prominent and some members have state-of-the-art stuff. There's one EP helicopter the owner claims has the equivalent of 3 or 4 HP (don't remember exactly) but I’ve probably seen this thing fly 50 times and when the pilot flips it, the rotors make a pretty good "whump" and on the average it's nosier than any electric plane I've seen. I can’t imagine any electric plane being louder, but in no way would I describe it as being “loud�. I use stock and pitts mufflers on two-strokes up to .91 size. All electrics and four-stroke glow planes seem quieter than my models. At our field and others I’ve visited - all glow helicopters, all twins and multi's and all gassers (which probably do have the potential of being quiet) are all louder than my R/C models.

If the noise problem was somehow solved as in planes could be made totally silent, those who have no use for our hobby/sport would more than likely find some other reason to complain. I firmly have much reason to believe that the alleged irritating noise our engines make is simply a pretext that the non modeler public uses to (in their minds) make the neighborhood skies safer by getting rid of those noisy and dangerous toys that grown men should grow up and not be playing with.

CCR

Safety first, Mommy.[:'(]

If you want to read about REAL noise problems from aircraft. And how it has probably poisioned people to us. Take a quick look at a website I stumbled across.

www.nonoise.org

Is this just your way of justifying making whatever noise you desire? Something like "they're out to get us anyway, so reducing noise has no value".

No, I'm saying that noise is just one part of the problem, as even sailplane and electric fliers are being kicked out, so it can't be a noise problem. By all means try to reduce noise, but in many cases, as you say, reducing noise had no value in the outcome.

CCR

Agreed, there are more issues than noise. However, in MANY cases it has been the primary cause of field loss. Way too many people are in denial and fail to comprehend how incredibly irritating the constant buzz of an R/C plane can be.

Who wears earplugs at RC fields ?

Only the guy cutting the grass.

BINGO!!!

I now know why people near our fields complain.

No plane excedes the DB limit. True. Times 6 of them up there is, 6 X louder and being high up spreads the noise over the noise absorbing trees and bushes.

Duuh. How do we solve that part of the problem Boss ?

Huh, what was that? I can't hear you!

cyclops2-

The sound sources (different models) are uncorrelated. In that case, each doubling in the number of sources increases the resultant level by 3 dB, assuming the different sources are equal in level. For six sources, that works out to a resultant about 8 dB greater than each contributing source. It is important to consider this in calculating the sound levels your club site as a whole is emitting. A club noise abatement rule should include the number of models allowed to operate simultaneously.

Abel

p.s.: Re www.nonoise.org, consider it a valued resource, even if you only view it in the "know thine enemy" sense. There is a lot of useful info in and linked to that site that can help you get along with neighbors, and if necessary to mount a defense against unreasonable ones.

Explain your use of the word uncorrelated.
I see the the planes as often flying in the same directions and heights. That would mean a maximum amount of noise is striking some homes repeatedly during a day due to the mandatory "racetrack" pattern required.

The old non AMA use would largely eliminate 6 X louder problem. True or false ?

Now this IS a good idea. Know thy enemy .

So far we have identified several issues in this thread. One issue, some folks are dealing with is vague and subjective noise laws. These clubs are, in my opinion at greatest risk of being subjected to harassing complaints, valid or invalid.

The 90db muffler concept was introduced during my time in this hobby. Perhaps, we as consumers can voice our interest in even quieter engines to the manufactures. It would be in the manufactures interest to help preserve the market for their products.

I owned a Jetski a few years ago. It was powered by a two cycle engine. During the 6 years that I owned the Jetski, I learned that many people living along lakeshore property found the noise made by these machines offensive. Many lakes around the counrty banned or restricted the use of Jetskies because they were loud. Often the charge against the Jetskies was that they polluted too much. The market responded. Honda produced a 4 cycle powered Jetski that was quieter and cleaner.

I believe our hobby can respond just as the Jetski sport responded. We must make people aware that noise is an issue. We can find quieter engines such as 4 cycles. We can reduce the number of planes permitted to fly at one time.

We must meet this challenge head on. We must be responsible and good neighbors in our communities.

And as for knowing thy enemy : It would not be a very bad idea to monitor or even join organizations formed around the issue of noise pollution. Perhaps a voice from within could penetrate their discussions and even steer them in a reasonable path albeit covertly.

Nothing stays the same. We are all old enough to know that change happens. We must examine our own ability to modify our behavior as our environment changes. If/as noise becomes a larger and more pressing issue, we must fight for our rights while at the same time we must adjust to the ever changing "reasonable" person's concept of unreasonable noise. With time and urban sprawl will we soon be face to face with that "reasonable" person.

By uncorrelated I mean not mutually or reciprocally related. Sounds sum as vectors. When two sounds are of the same frequency and phase, they sum at any instant in time to a level that is twice as great in magnitude (if they are at the same level), i.e., the resultant is 6 dB greater. Some will question that and say it should be 3 dB, so I should remind them that we are talking about sound pressure levels, that is potentials rather than power measures. Sounds that are dissimilar in frequency and phase sum randomly from one instant to the next, and the resultant can only be quantified as an RMS sum over some finite interval. The RMS sum turns out to be 3dB above the component sounds. Examples of sounds of identical frequency and phase summing (said to be a coherent sum) are a monophonic sound played through your stereo. If your speakers are properly phased and balanced you hear the combined sound 6 dB louder apparently at a point midway between the speakers. If the speakers are miswired to be out of phase, the sounds are reciprocally related - still identical in frequency but with peaks and troughs in the waveforms opposite each other. In that case the vector sum of the sounds is -6dB relative to either, and you have a sound 'hole' in the middle. Similar relationships exist between prop blades, which is why prop noise is directional, peaking 10-20 degrees behind the plane of the prop disk. Prop and intake/exhaust sounds are related in frequency, at harmonics if not always significantly at fundamentals. The exhaust sound phase can be modified with reactive elements, and this leads to a possibility of cancellation between prop and exhaust emissions - but that's a whole other topic. Just a hint - ever notice a model with a tuned pipe that seemed much quieter than you expected? A tuned pipe has large capacitive reactance (compliance in acoustic terms)...........

I'm not familiar with a club field that mandates a racetrack pattern, nor with any AMA rule that does. That notwithstanding, I think you should consider 'persistence' as it relates to noise annoyance. It has been well established by research in the field that how often and how long a noise emission lasts is an important parameter in any measure of its propensity to annoy people. That is why the measure 'equivalent loudness' Leq is often used to characterize noise, in civic ordinances for example. Rather than instantaneous levels, average levels over some specified time period, often one hour, are used. The instantaneous levels could well be greater at some receptor's location under the situation you describe, but I think for practical purposes what counts is the level emitted at the center of the pattern(s) flown, however they meander.

Abel

For anyone interested in the 'how to' of the sound surveys skerrin mentioned, the first one conducted is documented in the 'Sound Advice' column in the AMA News section of the November 1999 Model Aviation. The MA archives are a bit awkward to navigate on the AMA site; probably the easiest way to get there is to search on AMA News November 1999 and page forward to his article.
As he pointed out above, in the absence of objective measurement the law basically reverts to subjective judgement of whomever is in charge of the hearing. Forewarned is forearmed. Nothing is certain when you are dealing with the civil laws and well-heeled opponents, except that if you are not prepared to answer to them you will certainly lose.

Abel

If you go to the San Diego County Code of Regulatory Ordinances ,they have listed some base line sound levels and common everyday sources for comparison. They list things like washing machines and air conditioners. Surprisingly, both are rated far above 65db, if I recall correctly. A copy would surely be worth bringing to any hearing along with your own sound measurements.

Thanks for finding that article. I never would have looked for it. Our club is in the process of negotiating a new flying site. There are two neighbors that have expressed some concern about possible noise from the site. One is approximately 120 yards from the closest boundaryand 370 yards from the runway, the other is approximately 170 yards from the closest boundary, and 420 yards from the runway. I think we will propose performing just such a survey after opening the field. Our local jusrisdiction has a 65 db limit at the property boundary, so we can use the survey to either document compliance, or modify our operations.

Brad

March 2006 Issue
Friday, March 03, 2006


Is Your Club “Engaged� with the Local Community?
by Dave Brown, AMA President


I’m not referring to being prepared to marry—although in many ways the relationship is similar. What I have in mind is the relationship between your club and the community in which you reside.

When was the last time your club did a community project to raise its positive visibility within the society in which you exist? If your answer is “I can’t remember,� “I’m not sure we have,� or any similar response, then this is a good time to start thinking about what you can do to enhance the stature of your club within your community.

A number of clubs seem to think the secret to survival is to remain “hidden� from public view. I suppose that works for a short time, but in the long run, it will never be the answer. Clubs who try to remain hidden are the ones that are suddenly surprised to find themselves without a flying site and with no options on the table.

Think about it. Many of the organizations which thrive in the community do so not because of what the organization does for its members, but for what it does for the community. It doesn’t take much effort to reap a great reward. If your club is willing to give a little to the community, its people will pay you back with increased levels of respect, support, and most importantly, tolerance when you need them to help you through a difficult time.

What can you do? Many things! How about conducting a charity fun-fly? Invite local people and modelers from neighboring clubs over for an event and dedicate the proceeds to a community charity. It doesn’t hurt if the charity you select happens to be the mayor’s favorite. Surprisingly, it doesn’t seem to make much difference how much money you raise! This is one area where it really is the thought that counts.

Have you ever thought about sponsoring a scholarship at a local school? I don’t think there is any way that your club can get more positive publicity per unit dollar than this.
Think about it! The scholarship gets publicity when it is announced, when it is awarded, when the recipient starts school, and any other time the club draws attention to it. That is a publicist’s dream and it’s all positive publicity. It’s also one of the few times that making the front page of the paper is a good thing! It doesn’t have to be a large dollar amount: $250 or $500 will help a lot.

Does your town have an annual parade on Veterans’ Day, Independence Day, Easter, or another holiday? Why not consider putting together a float with many model airplanes on it and get the club involved! Believe me, this can be a lot of fun and the public response to your club will be far different than if you try to “hide� your existence.

I’m sure you can put yourself into the shoes of the mayor, sheriff, police chief, or councilman who must deal with a person who constantly complains about the model airplane flying field. It doesn’t matter that his or her complaints are unfounded or unreasonable.

Those people have to deal with the constant complainer and unless there is some good reason for them to go to bat for you, it’s far easier to simply shut you down than it is to deal with chronic complaints.

On the other hand, if your club has become a positive contributor to the community through local projects, it’s much more likely neighbors will be more tolerant of your club its activities and that officials will support you and have some ammunition with which to convince anyone who does complain that you should be allowed to continue to fly your model airplanes.

Hmmm … the longer I think about it, this is beginning to sound more like a marriage to the community!

Can anyone honestly tell me why.................

the Corona R/C Club lost their Highgrove field last year and being threatened to lose the La Sierra field?

the Circle City Flyers Club who have a nice paved runway and 200 ft carport shelter in a remote box canyon, is talking about moving their field to another location.

the Pomona Valley Flyers also with a beautifully paved runway, hearing rumors about them losing their field to an RV Park.

to name a few..... WAS IT REALLY THE NOISE???

What is AMA doing about it....? What are we as pilots doing about it...? I know what I'm doing... I'm one of those who's saying to HELL with it and going to "outlaw" park flyers and flying in the field just beside my house...... Advantages... NO club BS or paying dues to anyone. Ask yourself...where are you going to be???

Fliers 1, WOW... how long did it take for you to retype this?....Good Job!!!

Now that's what I'm talkin' about..... Isn't that that funny.... Dave Brown now thinking of this topic too... Maybe now they at AMA are finally recognizing this problem and going to deal with it before they loose out too?

LOOK out you old "fuddy duddy farts", here comes the new and improved model aviation sportsman community action hero!!!

Guys/Gals, just for fun...... What shall we call him?????

Promise?

Just a point of clarification, if you will . . .

When you write "they at AMA", to whom are you referring ?

The fifty-odd paid employees at AMA HQ ?

Or do you mean the elected officers ?

Or do you mean the dozens of sundry volunteer assistants ?

Or do you mean "they at AMA", as in the membership itself ?

The reason I ask is that you may have noticed that there is no AMA Grand Event this year. The reason there is no AMA Grand Event is because the two clubs which were bidding on hosting the event opted out when they discovered that Muncie was not going to send a group of folks to run the event, and that the club was supposed to run the event themselves, the same way sanctioned events are run.

Just who are "they at AMA" ?

J_R,

Attacking me here too, eh? Did I strike a nerve.? Welcome back.... I thought you said you would not post in this thread again.... What happened?

Archerry-
Welcome to the dark side, the world of We the People.

Just make sure you always have a pal or two as spotters as a resposible StreetFlyer:
"Car Car Car! Waive Off!"