Peter wrote:
I thought the main job was using o2-compatible materials (and avoiding most types of grease etc) not flush dirty hoses with some solvent
Generally, all newly produced O2-compatible equipment should be O2-clean but if not properly packed and/or not kept out of influences of non-compatible dirt, you have to clean it.
Peter wrote:
Let me know how you get on so I can update that oxygen article. A vast number of people follow it
So I’ve got two firms that have responded;
1) Undersea Centre Ltd
1087-BN Bullnose charging clamp £120.36
https://tinyurl.com/1087-bn-charging-adaptor
5044-2 2mtr o2 hose £134.48
https://undersea-centre.com/mixed-gas-charging-hose-green-3
1082 232 bar din £23.50
https://undersea-centre.com/male-din-232-bar-to-g1-4-male
1076 CGA 540
https://undersea-centre.com/cga-540-oxygen-to-g1-4-male
1080-B (This two part together to convert DIN to CGA 540) £57.59
https://undersea-centre.com/body-only-g5-8-female-din-to
£402.93 with VAT
2) Narked at 90
Male UK Bullnose-232 Bar Female Din £26.65
https://www.narkedat90.com/bnuk232-male-uk-bullnose-232-bar-female-din.html
Blending Whip With Analogue Gauge £174.54
https://www.narkedat90.com/bwag-blending-whip-with-analogue-gauge.html
Then similar to make up the connection to fit to the bottle, but I may have it. £74.40
https://www.narkedat90.com/1134-1080-b-nevoc-w30-to-232bar-female-din.html
I already have this with the bottle so may not need to spend the extra £74.40
https://www.navboys.com/CGA540ADAPTER.html
£201.19 with VAT
I need to suss which one is right, and what parts are needed for that hose on the 1.5m end connects up to the CGA540 adapter from NAVBOYS.
I was studying the options for oxygen. What I have found is that I could buy a 10 liters, 200 bar bottle (that’s the smallest available for oxygen with 4.5 purity) With that purity level pretty much all the contamination is negligeable: water 5 ppm, CO+CO2 0.5 ppm, etc.
It has DIN 477 Nr. 9: G 3/4", which I think would host a CPC-4 port:
https://www.mhoxygen.com/product/din-477-9-2g-gauge
12 kg empty weight, 2000 liters of oxygen. Cost is 150 EUR, plus 133 EUR deposit, and 0,7 EUR/day rental for the bottle.
Does anyone know possibilities to do refill of MH cylinders in Austria/Slovakia or close to Vienna/Bratislava?
Can anyone recommend a portable oxygen system for 4 people in a TB20, up to say around FL160 max with a duration of up to 4 hours?
Probably want at least 8 hours duration from the bottle in order to cover outbound and return, although not all the flight would be at altitude….
thanks
Hi Peter
Thanks for this – we’ll be flying 4-up, so it will need to go in the baggage compartment; hopefully without taking up too much of our weight allowance and space.
Any ideas on something smaller, and do you know if it’s possible to pipe the O2 from the baggage area without any problems?
Many thanks,
Chris
I don’t think you can use longer pipes to the cannulas, because the O2D2 regulator needs to sense the start of the inhalation cycle reliably.
So the O2D2 (you will need 2 of them, like I have) will need to be located so that all four people can use the standard cannulas.
The pipe to the O2D2 can be extended as required. It is low pressure.
The problem with the cylinder being in the luggage compartment is that the pressure gauge is not visible unless you can reliably get one of the rear passengers to read it. That is likely to be unsafe, especially if they are kids. Any way around this involves a high pressure pipe and is a whole load of complication. It is what is done in installed systems – cylinder in the back, gauge in the panel, etc.
Let me also state the obvious: a TB20, like any other IFR 4-seater, cannot carry four “modern size” people and full fuel 
And if you want to fly a 4hr trip then you need practically full tanks; even though the TB20 will fly for say 9-10hrs, the matrix of avgas availability etc in Europe drives a cautious assessment of alternate airports.
Hi Peter
The four will usually be myself, my wife & 2 kids (circa 200kg/500lb) – at most it would be 2 males + 2 females (@ circa 260kg/570lb) total.
My understanding (and I will be VERY happy to be corrected!) is that the TB20:
has a max load of around 500kg/1100lb
full tanks = 88 US gal = 320ltr = 225kg @ SG 0.70
fuel burn @ FL100 / 150kts TAS = circa 40 litres/hour = flight time of 8 hours no reserves
Full tanks @ 225kg + pax @ 260kg = 485kg + O2 + 15kg = 500kg…. JUST on max weight, but I agree, not ideal.
However…. 6 hours’ fuel would be 240ltrs / 66 US gal – which at SG 0.70 = 170Kg. plus max pax load of 260kg = 430kg, which is much more comfortable as far as EO performance, climb performance etc. with potential divert of 1 hour and reserves of 60 mins.
Do you think these numbers stack up, or have I got my maths (&/or information!) out of sync?
Appreciate your advice on this…. I’ve been flying a long time, but not in anything with less than at least 2 jet engines & a pressurised cabin!
In Europe, 2hrs’ fuel at the planned destination is often cutting it close. I know lots of people do this, and much worse, but one day you will regret it. This is not a jet which can fly the diversion leg at 400-500kt TAS and then land with CAT3 And winds have a big effect, on longer flights.
It should work however, in reasonable wx. If wx is CAVOK over a vast area and you are heading along a string of usable airports, then you can cut it closer. But only if you have a fuel totaliser.
