Recently, my friend and I are flying and some interested onlookers asked some questions like these,
<span style="color: #000000">
What kind of nuisance (Iwas likeWHAT?! )and noise levelsis producedfrom control line aeromodelling activity?

<span style="color: #000000">Does the flying activity pose any safety concerns? Will a safety buffer be required or a nylon netting to keep the aeromodels within the flying circles necessary?

Regarding the noise levels,hasthere beenany clubs that measured the level of sound produced by the engines? How can i define the level of noise?

Thanks alot for your help guys!

Reeve</span></span>

No nuisance.
Noise levels under 95db

No safety concerns when there is adequate fencing to keep spectators, their children and pets outside the flying circles.

Back in the 50s, I helped the control line club get a public park built for "hobbies". Two paved flying circles were built at one isolated corner of the park. No fences were included. The park included an R/C area, also with no barriers. The park has an area for R/C cars (basically unused), the R/C field (very active), the C/L circles (regularly used by a relatively small number of guys), a soap box derby track (used once a year), and a large covered pavilion (used frequently by couples and such and a constant problem for the police). AMA is not required as the city insurance is what the city cares to have for coverage.

Over the years there have not been any accidents that came close to threatening the continued use. The attraction of the mild isolation to gays and for drug deals is really the worst threat to it's continued existence. However, the C/L flyers have repeatedly had problems with park users, their children and dogs coming through the circles and over the lines. Had there been a fence to begin with, there would never have been any trouble.

I also helped get a park at a much larger city nearby. They had the money and sense to put up very good fencing. There hasn't been any problem what so ever.

Park administrators are not put off by the honest discussion of the possible dangers. Putting up a fence is nothing to them. They do it all the time. So don't shy away from the topic.


How to define the level? Same way IMAC, precision, and a number of disciplines do. Quote a noise level in decibels. I think somewhere around 95 is the going number, but you should look some of them up.

If you are dealing with a government, the adminsitrators will respond positively to any formal looking documentation you can provide. The AMA has a fair amount written on the subjects. It'd provide a good example to follow.

Thanks alot da Rock, your post has provided much info! greatly appreciated =)

Not trying to under cut da Rock, however here is one item that lost several facilities due to noise from CL models up in the Chicago area back when I was a very much (almost only) CL flier. (1968-1973)

That is the CONTINUAL noise produced from one spot and the somewhat kind of wavey sound-track produced from the engine going in a circle. Whereas RC does drone, it moves around a bit and seems less bothersome in the distance than the ground-level CL engine. Back then no one in CL used a muffler. Most do not, even now, especially combat and racing.

You may wish to address this point with your fliers. The long time continual whine of the CL engine disturbed more folks than any other complaints that I was ever associated with.

On the other hand, some folks claim "Noise" from Glider fliers. Who knows what people will complain about?

Is there any possibility that there is the "noise pollution" generated by the aforementioned cyclic modulation (scream from Combat), the thunk/thud of impact, the devastating following silence of blackhole suckiness and then the elevated epithet DB level after a wicked gnarly crash? That might lose ya a flying field or two...

yes, noise is the main concern here... im sure residents will be happy to hear a loud thud followed by a long ohhhhhhhhhhhhh.......... in contrast to the loud and high pitched whine of the engine, =(

i hope the authority will grant us the land.. i have no idea on how to relate to them the noise level/ produced..

Reeve

Do you fly somewhere now? Are there houses nearby?

Go fly and have someone hang out where the houses are and listen. Have him listen for sounds that're normal to the area the houses are in. Compare the loudness of the ambient noises to the sound of the models. Then hope the authorities consider his testimony of importance. Consider using a tape recorder.

And consider telling the authorities that models produce noise in the 95 decibel range. And that every model flown at the new site will have a muffler attached, that you will provide a sign if they wish.

Who are these authorities? We have Parks & Recreation Departments here in the US. Many of them look favorably on providing facilities for special interest groups. C/L is an activity that needs very little space compared to many hobbies. We very often are considered for land near airports or noisy industry. We often get permission to use de-activated land fills and such. It makes the city governments look good to provide for the people and to use less valuable land.

Just drowned out the airplane noise with boom box noise, apparently boom box noise is acceptable to those bothered by combustion engine noise...

We annoyed the hippies in the park interrupting their rock and roll with airplane noise during the 70s

When the hippies got older and some into public office we lost our nice field of 4 paved circles with CD observation tower club house.
Replaced by badly needed tennis courts that no one used for over 10 years.

David




Guess who runs our country now.

Houses would be nearby. private houses. Thanks da Rock, i would check out the ambient noises of the area, though it seems to me that private estate areas would be very quiet..

Regarding Mufflers, some engines do not come with mufflers, for eg the Cyclon 061 does not have any, (or any that i know of). Cox 049 TDs, I know that there are Rc mufflers out there but i dont know if will they be usable for C/L.

Land is a very valuable asset here in Singapore, it may take months to wait for the authorities to reply to our request, our requested area is a park.. with private estates around. Which is why noise is the main concern, i will tell them about the 95 decibels.

Hope the land is approved!

Reeve

One of the fields where I fly occasionally has houses along the side. The club president taks each of the homeowners a fruitcake around Christmas. if you make friends with the homeowners, they may be more tolerant of your activities.

WOW, thats a great idea!

thanks Jim!

Reeve

Fytch,

Recognizing the density of people where you are makes conditions difficult, yes, I have recorded sound levels several times at local contests.

In the USA, our national aeromodelling club - Academy of Model Aeronautics - has posted a guideline of 90 dBA at 9 feet (approx 3 m). Using an inexpensive sound level meter, I recorded several contest events involving engines up to ~ 10cc. Most were muffled, and none of those read above the low-90 dB level at the closest safe distance from the edge of the circle. Combat, Racing and Carrier models occasionally went a bit higher, briefly - displacements from half-A (0.8cc) to .40 (5.8 cc).

We have an ample flying site area in Tucson, AZ, USA (where the VSC are traditionally held since 1990). At slightly greater distances from the models in flight, the sound levels drop rapidly. The distance I measured from was between 15' (~5 m) and about double that. The borders of the flying area to the nearest allowable spectators were three to five times as far on all sides. Sound intensity where they were allowed, thus was quite a bit less. The doppler effect of the sound does bother some, but at a reasonably low level at the location of uninvolved neighbors, that should not kill you efforts.

Control-line flight also has the advantage that the range the noise can reach is sharply limited by the low maximum altitude. No one can fly above about 25 m with the engine going. Combat models require shut-offs if they break away, so the sound stops almost instantly.

Best of luck in securing a flying site! If you can locate several others interested, that will add support in your efforts with local authorities and neighbors. We, up here, still have chronic complainers, as Horrace pointed out. If they are clearly a minority, and a reasonable standard of noise suppression can be demonstrated, they might not carry the day...