How much CO2 is too much?

dteubner · 6th September 2005, 04:45

Quote: (Originally Posted by MikeH)

Take a look at the chart again. The number that you are looking at, which shows 719.6 at 1500 feet, is mm of Mercury absolute(mm Hg Abs)....NOT millibars, which is what the VR3 measures in.

On that chart, to get millibars, take the last column(kPa A) and move the decimal point one to the right. For instance - Sea level pressure is 103.3 kPa, and 1013.3 mb.

For accurate conversions, use http://www.onlineconversion.com/pressure.htm ..

Mike

My mistake, apologies

Dave T

abowie · 6th September 2005, 05:41

Quote: (Originally Posted by Underwaterbear)

...or you could just remember that over the first 10 000 feet atmospheric pressure lapse rate is about 32 millibars / 1000 ft.

If they were heading from Bikini to Majuro, technically the aircraft should have been flying at 9500 ft since the flight is south east...but who knows what they do out there

Very clever. From where I was sitting it looked to be a bit over 9000ft on the altimeter.

Now amaze me by explaining why heading SE makes a difference :-)

wizbang · 6th September 2005, 06:00

Quote: (Originally Posted by abowie)

Very clever. From where I was sitting it looked to be a bit over 9000ft on the altimeter.

Now amaze me by explaining why heading SE makes a difference :-)

Don't you docs know anything (galavanting all over the world).

[(Just joking i don't have a clue either

)]
Would it have anything to do with thermals and directions at different altitudes.
At one altitude it travels one way at x time of year and at this altitude it travels another direction, therefore if you want to travel SE then try for 9500ft to gain the tailwind.

Underwaterbear · 6th September 2005, 06:14

Quote: (Originally Posted by abowie)

Very clever. From where I was sitting it looked to be a bit over 9000ft on the altimeter.

Now amaze me by explaining why heading SE makes a difference :-)

Hmm...warning

Most of the flying world chooses cruising altitudes below 10000 feet using what is known as the hemispherical rule. You can google it I'm sure but in a nutshell it means for headings of 000 - 179 deg you fly odd thousands +500, and for 180-359 deg you fly even thousands + 500 It helps keep the tin birds from smacking into each other.

In some parts they fly the more complex quadrantal rule...but that's just confusing

Clear as mud

ofg-1 · 4th October 2005, 16:51

The amount of CO2 depends on what kind of head you wish to have on the mug. Of course, you could add a bit of nitrogen to your tank such as you do with Guiniess, to get more even bubbles throughout the brew. If all you have in the mug is foam, then you have too much CO2.

(That is what you mean isn't it?)

Sutty · 10th January 2006, 23:22

I tried taking a full breath of about 70% CO2 once, Iwouldn't reccomend it, felt VERY dizzy very quickly, and generally like Sh*t for a minute or so.

Vaguely remember the hemispheric rule/quadrantal rule from learning to fly a microlite a few years ago - basically designed so that planes flying towards each other are at slightly different levels, seems sensible!

6th September 2005, 04:45	#11 (permalink)
dteubner Pedant Current Rebreather/s: Sport Kiss Classic Kiss Other Rebreather/s: Join Date: Mar 2005 Location: Adelaide, Australia Posts: 216	Quote: (Originally Posted by MikeH) Take a look at the chart again. The number that you are looking at, which shows 719.6 at 1500 feet, is mm of Mercury absolute(mm Hg Abs)....NOT millibars, which is what the VR3 measures in. On that chart, to get millibars, take the last column(kPa A) and move the decimal point one to the right. For instance - Sea level pressure is 103.3 kPa, and 1013.3 mb. For accurate conversions, use http://www.onlineconversion.com/pressure.htm .. Mike My mistake, apologies Dave T
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6th September 2005, 05:41	#12 (permalink)
abowie Fighting Girl Current Rebreather/s: Sport Kiss Other Rebreather/s: Join Date: May 2005 Location: Land of Oz Posts: 573	Quote: (Originally Posted by Underwaterbear) ...or you could just remember that over the first 10 000 feet atmospheric pressure lapse rate is about 32 millibars / 1000 ft. If they were heading from Bikini to Majuro, technically the aircraft should have been flying at 9500 ft since the flight is south east...but who knows what they do out there Very clever. From where I was sitting it looked to be a bit over 9000ft on the altimeter. Now amaze me by explaining why heading SE makes a difference :-) __________________ Andrew Bowie Rebreather-friendly Buddy
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6th September 2005, 06:00	#13 (permalink)
wizbang WEB MERMEN Current Rebreather/s: Inspiration Classic Dolphin Home Build Other Rebreather/s: Not Bought Yet Inspiration Vision Evolution Prism Topaz Sport Kiss Classic Kiss Dolphin Home Build Join Date: Feb 2005 Location: Perth Australia Posts: 385	Quote: (Originally Posted by abowie) Very clever. From where I was sitting it looked to be a bit over 9000ft on the altimeter. Now amaze me by explaining why heading SE makes a difference :-) Don't you docs know anything (galavanting all over the world). [(Just joking i don't have a clue either )] Would it have anything to do with thermals and directions at different altitudes. At one altitude it travels one way at x time of year and at this altitude it travels another direction, therefore if you want to travel SE then try for 9500ft to gain the tailwind.
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6th September 2005, 06:14	#14 (permalink)
Underwaterbear A Prismer in Megland Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: May 2005 Location: Seattle, WA Posts: 185	Quote: (Originally Posted by abowie) Very clever. From where I was sitting it looked to be a bit over 9000ft on the altimeter. Now amaze me by explaining why heading SE makes a difference :-) Hmm...warning Most of the flying world chooses cruising altitudes below 10000 feet using what is known as the hemispherical rule. You can google it I'm sure but in a nutshell it means for headings of 000 - 179 deg you fly odd thousands +500, and for 180-359 deg you fly even thousands + 500 It helps keep the tin birds from smacking into each other. In some parts they fly the more complex quadrantal rule...but that's just confusing Clear as mud
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4th October 2005, 16:51	#15 (permalink)
ofg-1 New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Sep 2005 Posts: 21	The amount of CO2 depends on what kind of head you wish to have on the mug. Of course, you could add a bit of nitrogen to your tank such as you do with Guiniess, to get more even bubbles throughout the brew. If all you have in the mug is foam, then you have too much CO2. (That is what you mean isn't it?)
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10th January 2006, 23:22	#16 (permalink)
Sutty Classic Kiss diver Current Rebreather/s: Classic Kiss Other Rebreather/s: Join Date: Jun 2005 Location: Glossop, Derbyshire, UK Posts: 786	Re: How much CO2 is too much? I tried taking a full breath of about 70% CO2 once, Iwouldn't reccomend it, felt VERY dizzy very quickly, and generally like Sh*t for a minute or so. Vaguely remember the hemispheric rule/quadrantal rule from learning to fly a microlite a few years ago - basically designed so that planes flying towards each other are at slightly different levels, seems sensible!
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