I have thought up a very low-tec solution. This was to use my foam drum teaching earplugs under my bog-standard spamcan Sennheisers, inserted into a new leather helmet from Pooleys. Cool 1930s aviator? No way! I look like an extra from Dr Who and the Cybermen.
The theory was that if I can teach, converse with and hear a student drummer battering away to backing tracks whilst wearing said earplugs, I should be able to hear the R/T and radio over the tight passive attenuation of plugs and headphones, if they were turned up high enough. The earplugs and protective seal should filter out the wind noise. The problem would be in the mic picking up and amplifying the ambient noise. It has a muffler, but that's only designed for breath-noise.
Did it work? Beautifully. Exactly as hoped! The R/T came through loud and clear (relatively) and I could hear the radio - though in the air the radio developed a fault, so I couldn't do a full test on my 'system'. And after we landed there was no extra tinnitus. The only problem was, as foreseen, the noise through the mic; but it only showed up when I turned my head and peered out into the slipstream. Not very good for lookout!
