Letsby: the ANVIS 9 has a dual power source, and can be powered by however the opertator chooses. Some mil outfits elect to use aircraft power, but most (in my experience) use the dual battery system. 2 seperate battery "slides" of 2 x AAs are available to power both tubes, with a switch to select between power sources.
What I was really after was what standard of acuity, gain and resolution you guys are stipulating. Did you go for the RTCA draft TSO or did the UK stipulate a model number?
TC: On the take off and landing question I was not refering to weather minima, I am asking why there is no provision for loss of visual reference on take off and landing due to brown out, white out, flare out, or goggle failure, etc.
Over here, in reference to the misunderstanding of the stowage issue, we say "goggled up" to mean the goggs are in the operational position and are being used, and "degoggled" to infer the non operational position, which is rotated up and away from the eyes in the ANVIS series.
I assume tc was measuring clearance whilst degoggled, not whilst they were stowed in the back of the helicopter.