Noise.

**dentman** · 08-04-2012, 04:06 PM

Not a good day!!!! my local club has imposed an upper noise limit on all aircraft of 82db at 7mtrs , so this morning when we subjected our IC models to the test, all 50 size models pasted ,most at 82db with all types of exhausts and mainly os 50/55 motors , but most 90's failed, with the exception of my srimoks , it made little difference whether it was an os 91hz or hzr motor with hatori or align exhaust , so that renders most club 90's useless until we find a combination that will pas the test, any suggestions other than the obvious 'go electric'! We could have cheated and reduced our rpm for the test but left them set at our normal idle up rpm of around 1900.

**Gixxer** · 08-04-2012, 04:13 PM

Who decided on the 82db figure and how/why?

**Jamin_00** · 08-04-2012, 04:13 PM

This ain't good but I think leccy's might be louder??

**liamm =D** · 08-04-2012, 04:18 PM

health and safety gone mad or what ? haha try suggesting taking the ban away again but supply every body with ear muffs

**cupracing** · 08-04-2012, 04:18 PM

Electric 90s are pretty loud actually might be louder than 90 nitro, it's just the noise is more pleasant

**Gixxer** · 08-04-2012, 04:34 PM

Originally Posted by liamm =D

health and safety gone mad or what ? haha try suggesting taking the ban away again but supply every body with ear muffs

I think the limit is about 87db in the workplace, so 82 seems really low.

Originally Posted by cupracing

Electric 90s are pretty loud actually might be louder than 90 nitro, it's just the noise is more pleasant

Sacrilege

**3D FLIP** · 08-04-2012, 04:37 PM

I think 82db is a guideline set by the BMFA

**Andy from Sandy** · 08-04-2012, 04:40 PM

There is a code of practice for the minimisation of noise from model aircraft. It has nothing to do particularly with health and safety as when this was drafted we hadn't gone completely mad.

The sound level and distance to measure it at is in that document. They are not hard and fast rules but if a member of the public complains about noise from your models the code will be put into practice. If you are not near anything for miles and miles you will never have a problem but if you are close to houses and especially a hospital or similar then obviously the rules will be applied more stringently.

If you lived near a model club and wanted a peaceful afternoon but all you could hear is the scream from 2-stroke engines I think even the most hardened modeller would start to get annoyed.

**sacko** · 08-04-2012, 04:41 PM

It's a BMFA guideline. Has there been a noise complaint?

**liamm =D** · 08-04-2012, 04:43 PM

ahhh i thought it was due to health and safety

**Boggy** · 08-04-2012, 04:43 PM

Originally Posted by Gixxer

Who decided on the 82db figure and how/why?

(a) Model aircraft should be fitted with a muffler wherever this is practicable, except in the case of competitive flying as described in c.(i) and c.(ii) below.
(b) Except for competitive flying as described in c.(i) and c.(ii) below, no model should be operated which gives a noise measurement at 7 metres of more than 82 dB(A).

good old fricken bumfa's

**3D FLIP** · 08-04-2012, 04:46 PM

more info page 74 http://www.bmfa.org/handbook/HandbookFull2010.pdf

**Andy from Sandy** · 08-04-2012, 04:46 PM

The BMFA are trying to help with a simplified version of the DoE code of practice. If a complaint is made about noise the local authority is not going to ask the BMFA they will refer to the code of practice.

**Gixxer** · 08-04-2012, 04:51 PM

Originally Posted by Boggy

(a) Model aircraft should be fitted with a muffler wherever this is practicable, except in the case of competitive flying as described in c.(i) and c.(ii) below.
(b) Except for competitive flying as described in c.(i) and c.(ii) below, no model should be operated which gives a noise measurement at 7 metres of more than 82 dB(A).

good old fricken bumfa's

Sounds like there might be a lot of helis over that limit.

Were the tests carried out in an open space with nothing nearby that the sound could be reflected off, like a nearby building?

Sounds like a bit of wire wool up the exhaust for the retest might be your only option