Biggin charged me £75 but I don't remember who that was.

Nobody really caters specifically for the private unpressurised IFR scene - in Europe it is far too small. So, the general procedure for filling at airports is to find a maintenance facility which does refills of bizjet emergency oxygen tanks. This is fairly rare but they do exist at many big ones - you just have to find them, which is potentially difficult since the stuff is all airside and the last thing you can do at big airports is go for a walkabout airside, poking your nose into one hangar after another. You need the right sort of filling adapter and it isn't a 540 nor anything to do with scuba. It's a small threaded fitting - I wish I had the details. A maint shop near where my plane lives does this refilling (so I discovered just after getting myself sorted with the rented BOC bottle) but he only caters for planes with this special fitting, which I gather is standard in the bizjet world.

What Bose means is that the MH kit uses simple bare-pipe fittings which enable a constant flow cannula to be plugged directly into the first stage regulator. You still need a flow adjuster of some sort in the cannula pipe because the 1st stage output is ~ 20-30psi and if you just poke a cannula into that, the gas will be gone in no time. This is what I do - I have two demand regulators, plus some constant flow (Oxysaver) cannulas which serve as either a backup in case the demand reg(s) jammed, or to serve rear seat passengers.

I use the MH O2D2 kit, and yes, you can plug a constant flow mask/cannula into the adapter (the one attached to the bottle). This would bypass the O2D2 in case of failure.

I got my kit (MH O2D2, bottle etc.) from AFE Oxford. They also do the refills 'while you wait' at £20 a time.

Ian

In answer to IO540's question the O2 fitting he is searching for a name for is generally a 1/4NPT thread fitting on american aircraft and and either a 1/4BSP or 1/4 Swage fitting in Europe. I have adaptors for those as well.....

The O2DT kit requires a first stage and the standard first stage has 4 ports with quick connect self seal ports. The MH oxysaver kits use flow meters and oxysaver cannula and these will plug into the ports. So you on a 4 port regulator you could have 2 people using the O2D2 and 3 people using oxysaver kits. In the even of a failure you switch to Oxysaver kits.

As far as O2 is concerned, if you take a Euro spec cylinder with a DIN477-9 fitting or CGA540 and a bullnose convertor to any gas station you will be able to get it filled for a couple of quid with the correct grade of gas. Linde Gas, Air Liquide, BOC etc. If you want paperwork to get fills from a SCUBA shop then I run basic nitrox courses, non diving just half a day in the classroom that will give you a cert to hand to a dive shop if they are really being that anal over filling. Saying that IO is the only person I know to have had a problem!

To fill a standard O2 bottle should not cost you more than a fiver anywhere which is 100 times the actual cost of the gas but will be covering cylinder rental etc.

Anyone who wants a fill is welcome to fly into me and get a fill while they wait for a fiver.

I hope that helps.