I heard a rumour from an ex-EFT QFI that there were currently issues with the noise levels inside the Tutor. It is something to do with the helmet not being ANR and bringing the noise levels within allowed limits. Possibly, the aircraft has been flying illegally since its introduction in 1999/2000.
He also commented that QFIs can now only fly 9 hours per week and if they fly 3 hours in one day, they must have the next day on the ground.
7hrs 58mins per week, actually. It's to do with the low-frequency noise, 80 and 100Hz and the fact that it's constant and loud, I believe. The limit is 1:35 per day, and no more than 8hrs per week as a rolling total. I gather that the helmet attenuates only the higher frequencies, perhaps because the lower ones are more of a vibration. The constant drone apparently vibrates the cilia in the cochlea, breaking them off and creating a notch in the hearing at that frequency. There's plenty of research material on the Internet.
We had yellow E.A.R. plugs to begin with but they a) made it v. difficult to hear the intercom, b) made an aural "goldfish bowl" in your head, as it were and c) didn't work, probably for the same reasons above.
Trouble is, I can't make out what difference the damage might make, except that it's illegal. The annual hearing test goes down only to 500Hz, and at Boots yesterday they went down only to 250Hz (and the audiologist was no real help). I can tell now that we had AR5 cutouts in our helmets on my first tour as my high-tone hearing is damaged, to some degree. And for about 18 months I have had a sense of slight deafness on landing, but I put it down to sticky tubes and a fast (well fastish
) descent.
It looks like technology is the only answer, apart from binning Tutor flying ...
BoW