Cockpit Noise Level

[Bryan Cotton]

Many years ago, I ran across an add to alter standard headsets for unusually noisy conditions like in military jobs.

https://www.cep-usa.com/dch-pdf
Some of my former Sikorsky coworkers had these in their Gentex helmets. They were highly recommended.

[daleandee]

I have used Clarity Aloft for a number of years. Problem solved and weight saved ...

Dale
3.0 Corvair/Tailwheel

[Skippydiesel]

Great idea - with one limitation - no sharing of headset, unless extra ear plugs available.

[DCASonex]

Also more headroom with those Clarity Aloft headsets. It is quick and easy to change the foam plugs, which come in multi-packs and can keep them for future use rather than tossing them out. I got a used Clarity Aloft set, but wife did not like the idea of the in-the -ear headsets, so got her a more conventional low cost ANR headset. Then one day she tried my Clarity Aloft. Then had to purchase a new set for her.

David A.

[funflyingguy]

thanks guys. i'll take a look at these other possible options.

FYI: i am sort of surprised that insulating efforts for engine/exhaust sound deadening, vibration dampening and wind noise abatement didnt help much (especially at cruise). in my plane, it seemed these were most likely the cause.

did anyone change out the aerovee straight pipe exhaust for small mufflers or resonators? (i recall articles here about home-made mufflers and a swiss-style muffler but not the result..)

jim

[Bryan Cotton]

I'll say two things:
1) Weight is the enemy
2) You can't afford to give up any AeroVee performance

[funflyingguy]

agreed. i am always mindful of the weight for my mods. and mufflers would reduce the power output also. this is an absolute last resort. but the trade-off for me is hearing announcements; therefore safety. i have to keep it on the edge of the table!

[Dave Wolfe]

Looking thru Peter's page it seems apparent the cabin noise is primarily engine/prop driven as we would have guessed.

Exhaust = .5 per rev x 4 (vw) = 2 pulses per rev
Prop = 2 per rev
Intake = 2 per rev as well

The FFT isnt going to help it will just show a big noise spike at 100 hz for the vw's

[funflyingguy]

ok. prop surprises and doesnt surprise me. setting that aside for the moment:

any idea where and what is generating the intake noise? is this the sound of the air coming through the aeroinjector / air cleaner combination or through the cowling
inlets? (mine is a dual purpose inlet feeding primarily the low mounted oil cooler with a 1" off tube feeding air to the aeroinjector)

exhaust doesnt surprise me. any idea if that depends upon where the straight, unmuffled exhaust pipe terminates at? (mine is just past BUT slightly above the lower
cowling deflector lip)

prop: mine is the recommended sensenich wooden prop. prop designs often affect the noise levels. curious if anyone has experimented with props and know of a
quieter one?

[Bryan Cotton]

I have used Clarity Aloft for a number of years. Problem solved and weight saved ...

Dale
3.0 Corvair/Tailwheel

I bought Adam a pair for graduation and he loves them. They are my next stop after I retire my Peltors. For now I need to redo some of the duct tape holding on the mic.

And, just a thought - you can chuck a pair of passive or active ear muffs over the Clarity Aloft headsets and you really won't hear anything. All for approximately zero weight, and no risk of it not working.