noise certification or pandora's chocolate box

[djpacro]

Not a lot to do with CASA. If you don't have noise certification you will find that the exemption comes with some conditions. This law is not new.

Blimey you people go on with a lot of crap. ....

I withdraw my crappy statement and I will try not to bother you again.

 

 

[facthunter]

Years ago when I was more inclined to read rules, there was a reference to this certification, somewhere in our rules, so I think it has always been there. Many aircraft are straight through exhausts, (Even the big pistons) In Europe they have very stringent requirements where you can hardly hear them. Probably makes for a much more pleasant ride, but the system would be quite exotic and retrofitting would not be too practical. There is a safety aspect to this too. Mufflers have often had baffles come loose and part block the exhaust gas damaging the engines. The exhaust system has to move with the engine or have an unreliable flexible connection. Simplicity is best and safest. Nev

 

 

[turboplanner]

I think even Henry Ford was still in overalls in the factory when those issues were virtually permanently solved FH.

 

 

[Dafydd Llewellyn]

I think even Henry Ford was still in overalls in the factory when those issues were virtually permanently solved FH.

Really? When was the last time you had a loose baffle in a muffler?

 

 

[turboplanner]

I did say "virtually", but my last time was when I put a crowbar through one about 40 years ago to get more noise.

 

 

[turboplanner]

"How about posting the offending regulation so we can see what the problem is."

 

Interesting how no one seems keen to spell out what exactly is the problem.

 

 

[Dafydd Llewellyn]

"How about posting the offending regulation so we can see what the problem is."Interesting how no one seems keen to spell out what exactly is the problem.

If you are talking about the noise regulations, I posted the link earlier in this thread. Go look it up. The basic requirement for GA aircraft in Australia is ICAO Annex 16, chapter 10. Much too large to post here.

 

 

[turboplanner]

I did look it up and I don't need to wade through definitions of "aircraft" and other irrelevant thanks, you could have been a lot more helpful to everyone.

 

What I did find after half an hour or so's searching was, and take this as very general because it could be subject to a few hundred other clauses of crap:

 

Measurement is 2500 metres past brake release, so the faster you climb the better the result

 

Maximum noise is 70 dB(A) up to 570 kg increasing to 85 dB(A) at 1500 kg

 

To give you some comparison, ADR83/00 requirement for a Heavy Truck over 320 kW power is 83 dB(A) measured at 7.5 metres from the vehicle.

 

At your altitude attained by 2500 metres, you will be much further away than 7.5 metres, and the noise reading will diminish with distance, so that's not a severe standard, and I wouldn't be surprised if some engines could achieve it without mufflers.

 

I have always used ADR83/00 or it's predecessor ADR 28/01 in Planning arguments, because that is the acceptable, and legal community noise level 7.5 metres from the edge of a road, and the noise level residents are being subjected to in a built up environment. That comparison has been very successful in settling noise disputes,

 

 

[Dafydd Llewellyn]

I did look it up and I don't need to wade through definitions of "aircraft" and other irrelevant thanks, you could have been a lot more helpful to everyone.What I did find after half an hour or so's searching was, and take this as very general because it could be subject to a few hundred other clauses of crap:

 

Measurement is 2500 metres past brake release, so the faster you climb the better the result

 

Maximum noise is 70 dB(A) up to 570 kg increasing to 85 dB(A) at 1500 kg

 

To give you some comparison, ADR83/00 requirement for a Heavy Truck over 320 kW power is 83 dB(A) measured at 7.5 metres from the vehicle.

 

At your altitude attained by 2500 metres, you will be much further away than 7.5 metres, and the noise reading will diminish with distance, so that's not a severe standard, and I wouldn't be surprised if some engines could achieve it without mufflers.

 

I have always used ADR83/00 or it's predecessor ADR 28/01 in Planning arguments, because that is the acceptable, and legal community noise level 7.5 metres from the edge of a road, and the noise level residents are being subjected to in a built up environment. That comparison has been very successful in settling noise disputes,

I asked you to look it up, because (a) I've used my monthly broadband quota, and (b) my recollection of the details is not perfect. Your reading of it accords with my recollection. Aircraft certificated prior to 1984 are exempt, I think, and those will be most of the wide open exhaust ones. However, the greatest source of noise by far is always the propeller.

 

 

[turboplanner]

Yes, the exhausts may not be an issue with higher speed props.

 

One of the first shocks to me was that Chev 350 engines made more noise from manifold resonance than exhaust.

 

 

[DrZoos]

We only have two offensively noisy aircraft locally. One is a jet (only flys once or twice a week) and the other is a Cessna 182 float plane that does scenic joy flights (five to ten or more times a day) . But the float plane is ridiculously loud compared to all other cessnas. Im assuming the engines are the same or similar so its likely the prop. Im assuming he has a fine pitch to get the thrust for take off on the water. He recently had a full overhaul and rebuild and it came back a LOT louder. Prior to the rebuild it was loud for takeoff and first 1000 feet only. But now its loud when ever he has more then moderate revs on board. Doesn't bother me but i do know its pressing some peoples buttons and its not helping the aviation "image".

 

I have no idea what would pass and fail that test turbo. But id reckon if any small plane failed this one would.

 

Hey turbo that 2500 feet test. Is that at full throttle??

 

See Nev im filling in the blanks..lol

 

 

[metalman]

Mmm the Cessna howl, if you don't already know Zoos the noise is the prop tips going supersonic, you can quiten it by winding off a couple of hundred revs on climb, I love the noise but it does annoy ground dwellers!

 

Recently was listening to a 182 meatbomber in our area and thought the pilot needs a bit of a talk on PR , climbing to flight levels full noise ,full fine is not good for the plane or the future,

 

Matty

 

 

[facthunter]

It's a pretty outrageous noise. Supersonic tips is a waste of energy. A few radials hit the alert too. A seaplane needs a bit of oomph to get off the water but after that..... Nev

 

 

[DrZoos]

Wonder if he is running it hard due to the float drag. He just flew over the entire town then heading back into the area to land with full prop noise like he was in a red bull air race. Doesnt worry me but i bet its annoying someone.

 

 

[turboplanner]

Hey turbo that 2500 feet test. Is that at full throttle??

Yes, full take off throttle, so the aircraft may be well below the regulation limit for most of the circuit. Careful mapping in Planning cases can solve a lot of heartache for flying clubs.

 

 

[Dafydd Llewellyn]

Wonder if he is running it hard due to the float drag. He just flew over the entire town then heading back into the area to land with full prop noise like he was in a red bull air race. Doesnt worry me but i bet its annoying someone.

Anything with a Continental IO-520 and a constant-speed propeller does that; TCM put the red-line RPM at 2850, so they could boast another 15 horsepower or so over the competing Lycoming (2700 RPM) at the time. The added RPM do not increase the aircraft's performance one iota; I recall some performance tests that showed you got the same climb performance at full throttle, at 2700 RPM - and it was a whole lot quieter. However, you'll never convince the pilots - they know it's producing more power at 2850, they can hear it . . .

There's a strip at Noosaville that was permanently closed as a result of an idiot who ran a meat-bomber operation there for several years, using a Beech Queen Air - which must be one of the noisiest light twins ever built. Take you seaplane pal out behind the hangar and have a quiet word to him, would be my advice.

 

 

[Oscar]

Irrespective of the actual db recording, the pitch, harmonics and frequency of noise intrusion is what drives people crackers. There used to be a float-equipped trike operating joyflights around Pittwater, flying around the hills that surround the water, and the whine from the Rotax gearbox combined with the constant (well, inconstant, really) changes of direction as it weaved around the houses had people tearing their hair out (and threatening ballistic retribution delivered in 80-gramme loads @ a muzzle velocity of around 1400 fps.) Imagine a dozen leaf-blowers on full song flying in formation 100 feet past your front porch, in an area that one can normally hear a possum fart... I live on a road that has about 80+ Harleys ride past twice a weekend - the place shakes, but they're done in two minutes; but the lone motocross rider that practices on his bloody two-stroke for six-eight hours a day about 0.5k away has me homicidal by day's end - and I happen to ride motorcycles..

 

I've had a Merlin on full noise pass about 100 feet away (utterly, utterly glorious noise that shook the cutlery off my galley); a 582-equipped Drifter five times that distance is really annoying. Guess which one of those generates more db?

 

If you want to drive someone mad, place them in a silent room with a clock that ticks irregularly. You think I am being silly?: look at line 4 of this song: http://www.abrsm.org/forum/index.php?showtopic=29174

 

Think about this: as a pilot, if you hear an engine suddenly change its revs, you look skywards. I'll guarantee you cannot ignore sudden and unexpected changes in engine noise.

 

The Pawnee glider tug operating out of Camden is the noisiest aircraft I have heard in ages (other than the Queen Air that sometimes passes over my farm which sounds like a coarse-tooth saw blade being passed through sheet stainless steel) and it flies out over a heavily-populated area - it will single-handedly kill Camden airport if it is not remediated. By comparison, the rumbling of a couple of Yaks/Numchuckas in formation that pass over my place fairly frequently is a peaceful, almost warm-feeling drone.

 

As a group, we cannot afford to ignore the effect that our noise may have on the non-aviation community if we wish to have access to airfields within a reasonable distance of 'civilisation'. I'm talking about airfields that have reasonable access to things like taxi services into a place to stay for the night when we are travelling; reliable fuel supplies, a sufficiently large flying population catchment area for a LAME or L2 to operate to be available to help us when we need repairs out the back of buggery..

 

We don't need to be irritatingly noisy - it's not as if we gain safety or performance by creating excess and annoying noise. Noise annoys people (pun intended!) and they take action: witness the rise of legislation against 'doof-doof' equipped vehicles, noisy motor vehicles, use of Jake Brakes for heavy vehicles, db limits for racing cars and road vehicles.. A properly-designed muffler system does not introduce back-pressure issues.

 

This is not an issue where 'our freedoms' should be questioned: the 'freedoms' that really matter are far more important than any imagined intrusion on our right to make as much noise as we like. We all live with this restriction every time we start our car to go to the shops. More than any other factor, if we get the backs up of the general population by demanding the right to create objectionable noise, we will be excreting in our own nests.

 

 

[turboplanner]

In my very quick scan of the regulation, I was stunned to read that the microphone results in the ICAO standard appear to be required to be doctored at the upper and lower ends of the spectrum - the upper end in particular being the area which grates on us when we hear it. (Mid range is rather like an air conditioner - hardly noticed.)

 

I hope I'm wrong with this, because that could cause legal issues where there was a noise dispute.

 

 

[Dafydd Llewellyn]

In my very quick scan of the regulation, I was stunned to read that the microphone results in the ICAO standard appear to be required to be doctored at the upper and lower ends of the spectrum - the upper end in particular being the area which grates on us when we hear it. (Mid range is rather like an air conditioner - hardly noticed.)I hope I'm wrong with this, because that could cause legal issues where there was a noise dispute.

The ICAO standard is required by the aircraft noise regulations, 1984, which are regulations made under the Air Navigation Act, 1920. I'm no legal expert, but I think that came under the heading of a Disallowable Instrument in the Australian Federal Parliament, and that makes it Federal Law. So to my limited knowledge, a legal challenge to that standard would seem unlikely.

 

 

[Old Koreelah]

Off-road motorcycles fought this battle decades ago: less sound=more ground.

 

 

[Oscar]

Off-road motorcycles fought this battle decades ago: less sound=more ground.

Absolutely right - and yet, there are still yobbos who ride around and intrude on private property (mine, for example) on MX machines with shrieking exhaust notes and that generates huge angst and police presence - I am not kidding here. We need to understand the negative effect that 'intruding' with excessive and unpleasant noise has on people and both develop and preserve a reputation as decent members of society or we will lose 'ground'.

 

 

[Old Koreelah]

I also suffer from damned noisy dirt bikes encroaching on our rural quiet. Looks like some battles are never won. The war goes on.

 

 

[Gnarly Gnu]

Did you put signs up warning them about the low level tensioned cables?

 

 

[Guest ozzie]

There's a strip at Noosaville that was permanently closed as a result of an idiot who ran a meat-bomber operation there for several years, using a Beech Queen Air - which must be one of the noisiest light twins ever built. Take you seaplane pal out behind the hangar and have a quiet word to him, would be my advice.

Never seen a Queen Air on the jump scene> But I suspect you are referring to Ramblers 'Twin Bonanza'. Two thumping geared supercharged Continentals.. I'm sure Macca would be pleased being called an idiot. Sure it was a direct result of the noise the T Bone made? What is there now?

 

 

[Dafydd Llewellyn]

Never seen a Queen Air on the jump scene> But I suspect you are referring to Ramblers 'Twin Bonanza'. Two thumping geared supercharged Continentals.. I'm sure Macca would be pleased being called an idiot. Sure it was a direct result of the noise the T Bone made? What is there now?

This is the strip I mean; I enquired several times about it, because I was looking for a site that I could use occasionally as a base for a day or two for aircraft cooling and climb performance testing over the water, along the beach just north of Noosa. That sort of testing needs smooth air with no temoerature inversion, and those conditions occur just offshore in gentle sea-breeze conditions. It's on private property; each time the answer was as I described. I've no idea what's there now. I suppose it could have been the B50; a Queen Air is just a B50 on steroids. Whatever, it did nobody a service by getting the place closed.