Silencers

[rightstuffer]

I saw a C-150 the other day with an external silencer. Didn't have a chance to look closely or more importantly, to listen to it. Anyone know the latest developments? Can they be fitted? Will the CAA allow them? What about weight/cost/performance?

[A and C]

the problem is that eny change in an aircraft requires the mod to be approved by the CAA or a company that is approved to do so.

So a minor mod will cost about £50 for the CAA paperwork , if the mod has eny performance implications then it becomes a major mod and the CAA will charge IRO £ 300/hr to look at it.

This is why no one will be the first to fit a silencer first the CAA cost and then if they issue a STC it becomes public property and the guy who did the work cant recover eny of the cost from eny one else who uses the STC.

[Cahlibahn]

I believe that CAA Certified Noise reduction kits are available for the following types from Skycraft Services in Cambridgeshire.

Citabria Scout C150/152/172/206
PA18/180 Super Cub PA 25 Pawnee 235 & 260
PA 28 Warrior Robin DR300 Robin DR400
Rallye 180T

[Tricky Woo]

[rant mode on]
In most cases the CAA does a reasonable job, IMHO.

However, this is an area where the CAA is letting the side down. The lack of approved silencer kits in the UK is having an adverse impact on pilots and public alike.

I honestly think that noise is at the root of a large number of threats to GA: Airfield closures? Noise! Complaints? Noise! Malicious accusations of low flying? Noise!

Seeing as 99% of the UK light aircraft fleet are fitted either with a Continental or a Lycoming, then isn't it time we got the various silencer kits that are freely available in the US and in Germany approved for use in the UK?

Shouldn't the CAA be addressing this by policy?
[/rant mode off]

[Genghis the Engineer]

Interestingly, microlights (which used to the source of many noise complaints) have to meet maximum noise output requirements. Nobody has ever imposed this upon light aircraft.

CAA fees, last I looked, were £61 for a minor mod, and £294 for the first 3 hours of looking at a major mod, and £98/hour thereafter. But the information that they require for approval of a mod is fairly stringent.

That often shouted-about incident where the CAA wouldn't approve a silencer on an SLMG was basically down to the hushkit manufacturer failing to provide the design information that they needed.

Personally I think the main problem is pilots who seem to feel happier at 1000ft instead of 3000ft so much of the time. I see them regularly in the village in which I live, where a higher altitude would be safer, easier for navigation, and clear of controlled airspace - yet they still insist on mucking about under 1500ft when there's no particular need. Also, why fly over a village when you can fly around it?

G

[TwoDeadDogs]

Hi there
Bags of sense from Genghis.
In this day and age,a 172,new from the makers,costing IRO IR£130,000,bearing the silencing qualities of a cement-mixer...a joke.Manufacturers should build decent silencers onto their craft from Day 1.The weight and cost penalty is not that large.
The same applies to older types on Permits which could easily be modded to be a lot quieter,in and out.Ever seen Bingelis' Jodel silencer mod?
regards
TDD

[Hersham Boy]

I'm with you on this - but a similar thread on the Flyer portal saw me derided for suggesting that the weedier end of the aircraft spectrum could be modified as such.

My POV came as a motorbike rider (and a newbie PPL-er) having seen adjustable baffling systems on race exhausts. Could the engine not be allowed to breathe free and noisy for take-off where the power is needed and baffled/stifled for cruise and approaches?

:)



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If it ain't broke - why not?

[Sleeve Wing]

West London Aero Club have recently been testing a hush-kit on one of their Warriors.
This has been a success and I believe that their Engineering Dept.has, or shortly will have, CAA approval for a standard fit on all small Piper models.
The silencer used does not cause any reduction in performance.

Having said that, I totally agree with Genghis that the best way to stop irritating the neighbours/nimbies/killjoys is to fly that little bit higher whenever possible.

[This message has been edited by Sleeve Wing (edited 24 March 2001).]

[A and C]

If you think that it is just noise that makes the NIMBY ,s winge forget it a guy i know was forever getting problems with noise when flying his model aircraft so one day he asked me to help him to fly his new model glider (i had to pull on a long bit of elastic to get the thing in the air) after about half an hour the police turned due to noise reported by some local !