Hi DD,
1) There is no battery - the headset works on the BIAS current from the radio/intercom system.
If this power source turns off, the radio and intercom will not work - and there will be no need for headsets.
2) The loudspeakers output is in accordance with the EASA/FAA TSO. In practice this means that you will need to have the volume control on the audio panel turned to 2/3 of maximum to have a comfortable normal level.
The headset does not have a build-in limiter, but the loudspeaker is not able to deliver enough power to kill off your hearing.
3) The passive noise reduction of the ear pieces reduces the noise with 5-10dB below 1,5KHz and 35dB above 6KHz.
This is opposite when compared to ANR headsets that will deliver a level of noise reduction at 10-15dB up to 1,5KHz and less above.
When wearing the tbone Aviation Headset you can hear everything at a reduces (safe) level.
When wearing an ANR headset you may feel you operate in complete silence.
You can use the tbone as hearing protection when doing a walk around, but it is not as effective as a cup-based specialized hearing protector!
When you're close to the APU, you shuld cover your ear with your hands as extra protection - as I am sure you would do if you were outside without any hearing protection or just the 'yellow foam plugs'.
Is this headset suitable for light aircrafts?
Well yes and no.
If you use the tbone with an extra cup-based hearing protection it will work very well!
As a stand alone hearing protection I would say no.
Having said that, we are in the process of having professional audiologist (who are also GA pilots) testing the tbone with various cup based hearing protections. The initial results are:
- Lower weight compared to David Clark (less than half the weight)
- Perfect noise reduction
- No batteri operation
- No noise in microphone TX (mike is out of the ambient noise)
So it seems very suitable in a single piston engine A/C when you add the extra protection.
We are also testing the tbone in a Robinson R22 rotor craft.
The results are very similar.
Hope that answered your questions!
Jan