View Full Version : Noise reduction headset

18th Dec 2003, 11:53
Greeting Gents;

I am flying B737 using the Sennheiser HMEC 45-KA noise reduction headset; the company is raising the issue of the noise reduction function affecting the aural alert warning system and the aural alert of enhanced flight deck door system.

I wonder if any other operators had any trouble using Noise reduction headsets. :confused:

Does anyone have comments on this?

Any information would be much appreciated. Thank you.

Happy Landings :D

Wing Commander Fowler
23rd Dec 2003, 18:53
Hmm... can't see their point here? Way I see it the system operates by replacing one continual background noise with an appropriate "anti-noise" - if that wasn't the principle then you wouldn't be able to hear anyone speak to you.

However, I do have some concerns over the "advantages" claimed. Used to operate turboprop hardware and a colleague who had ANR headset could never detect props out of synch and I would suspect there could be some form of defect with the aeroplane which COULD go unnoticed. Further - get a lot of guys telling me that these headsets are better for your hearing and they try to justify this by showing me how much lower the volume setting is on their ACP than on mine..... Fact is that the ANR sets have some amplification of their own to add to that of the ACP. Could prove this myself by bringing in my ghetto blaster and coupling an input to it from the intercom (probably get the sack for it) - a 100 Watt subwoofer next to your lughole would probably require the ACP setting to mins or below.

By the way I did try one of these magic sets few weeks ago and noticed little difference. It seemed to simply replace a mid range background noise with that of a lower frequency...... What's the real benefit I wonder?

Golden Rivet
23rd Dec 2003, 21:09
The Sennheiser HMEC 45-KA is good at picking up on radiated interference, could possible do with some extra screening.

On 757/767, its possible to pick up on radiated interference from the flight deck window heat system if you move your head close to the windshield !