BM:
>We are looking at introducing Primary missions (Scene calls) at night here, and we >will only be conducting them if NVG's are used. At the moment we fly Secondary >missions, ie hospital transfers, only at night, and that is only into known airfields or >Hospital pads.
That’s a great start and don’t let anyone back you off that point. Also, if your program has some outreach and training money/time, try to get out and work with the local EMS providers and setup ”canned” LZs, pre-surveyed for hazards. With enough of those, you can further limit your risk.
This is just speculation of course, but if we have a few more night accidents here in the U.S. attributed to CFIT, I could see and understand the feds stepping in and saying no more night flights without NVGs.
>Other than ITT, who else produces NVG's to the current standard? ANVIS-9 is the >standard at the moment, is that correct?
I don’t have an answer to that question. The ANVIS-9 designation might be a military term, so you might also see something like F4949, which I think is the ITT model number for aviator NVGs. Off hand, I don’t know of a European manufacturer. Do you have any European military pals to quiz on this?
The thing is, I think the important technical aspects of the NVGs are the image intensifier tube specs and power supply. So is essence, anyone who could meet the specs should be able to supply tubes to the industry. This is of course assuming the basic setup of the housing – adjustable and removable binocular, breakaway helmet mount and battery pack- remain the same.
One thing to consider is the FAA is pretty new to the aided night flight concept, so you can see they would want to certify things very conservatively and limit the equipment until things are proven.
An example of this is the PVS-7. The housing looks the same but you can get various quality tubes made by different companies as the guts with huge swings in price.
>What are the differences between ANVIS-7 and -9? I will check out DEP.
Can’t answer that either. Google says ANVIS-7 is some sort of heads up display thing though which I assume is mounted to NVGs. There also seems to be quite the variation in the same tubes. You can buy a high resolution tube, say with 64lp/mm of resolution, with a “normal” power supply(whatever that means) or a “gated power supply” and get different performance from the NVGs, I think in terms of the NVGs ability to work in high light conditions. Naturally, you will pay for this difference.
DEP makes tubes and looks like they got bought out:
http://www.photonis-dep.com/night-vision
One interesting thing I’ve found is the ITT tubes have a slight amber tint and a DEP XD-4 tube, for instance, has a slightly bluish tint.