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Nicked from somewhere else. I'll bet a couple of you can get an argument out of this. No names mentioned of course.
If anyone is interested in a deep dive story...heres a condensed version of
a reasonably deep one
Plan was 320m at an open ocean divesite in Phuket Thailand...charted depth
under the dive boat 414m-484m (keeps the anchor from dragging nicely
back gas was 5/76 gave a high END but this kept the HPNS undercontrol
nicely and made the next gas choice easier.
the drop down was smoothish, the dry suit gas was bottom mix (forget what
you may have read...argon...helium bad insulator etc blah blah blah).
This flows nicley and kept me nice an warm when the the water was 3-4'c.
The descent was stopped at 313m for a couple of reasons,
ascending at 15m per minute dropping to 10m per minute from 250m. The
subsequent gases all contained 30% N2 or less and the N2 values were
always dropping. many reasons for this.
the stops went well largely due to the support team and having lots of
spare gas.
Breathing high helium to the surface culminating in a 3 hour session from
9m to 3m on heliox was a very difficult experience. Helium cooled me from
the inside out when on open circuit, body has huge problem heating the
inspired gas , long hoses to the surface did a reasonable job raising gas
temps. vast quantities of warmed water consumed.
The Po2's were low so as to eliminate air breaks with their often
disastrous affects. Air breaks may work in a chamber but not too well
during a trimix dive (depending on size of dive)
Obviously back gas switches were out of the question , I had 8 other
trimixes to choose from, but all contained some N2.
Some unpleasantness occured when a long hose was swapped at the surface. My
tongue was sucked into the partial vacuum, but luckily the hose wall
yielded and i pulled my tongue free (now 6'' longer)
The deco plan was created on propietary software, but apart from the deep
stops placing and times looks similar to a traditional buhlman model with
the helium values changed. Deco ran 6 hours 40 mins...I surfaced exhausted
and suffered pulmonary toxicity for 3-4 days.
I have a deco plan analyser which can check plans created from even the
most comical dive software. When the interface is more user friendly (to
me!) I will send some details...you need to see it ! Any dive plan will
have its weakneses revealed both DCI/ICD related and oxtox and body work
load
Most planners generate deeper stops from the top down...this is just crap.
The free gas "miracle" dive planners need leaving well alone.
I am not claiming this as anything other than the deepest solo dive on
scuba, which happened to be (more importantly) the first without
significant DCI.
I appreciate this is a very brief message, if anyone is interested I can
send a detailed account.
cheers...Mark E
Sorry for nicking Brens job
Nicked from somewhere else. I'll bet a couple of you can get an argument out of this. No names mentioned of course.
If anyone is interested in a deep dive story...heres a condensed version of
a reasonably deep one
Plan was 320m at an open ocean divesite in Phuket Thailand...charted depth
under the dive boat 414m-484m (keeps the anchor from dragging nicely
back gas was 5/76 gave a high END but this kept the HPNS undercontrol
nicely and made the next gas choice easier.
the drop down was smoothish, the dry suit gas was bottom mix (forget what
you may have read...argon...helium bad insulator etc blah blah blah).
This flows nicley and kept me nice an warm when the the water was 3-4'c.
The descent was stopped at 313m for a couple of reasons,
ascending at 15m per minute dropping to 10m per minute from 250m. The
subsequent gases all contained 30% N2 or less and the N2 values were
always dropping. many reasons for this.
the stops went well largely due to the support team and having lots of
spare gas.
Breathing high helium to the surface culminating in a 3 hour session from
9m to 3m on heliox was a very difficult experience. Helium cooled me from
the inside out when on open circuit, body has huge problem heating the
inspired gas , long hoses to the surface did a reasonable job raising gas
temps. vast quantities of warmed water consumed.
The Po2's were low so as to eliminate air breaks with their often
disastrous affects. Air breaks may work in a chamber but not too well
during a trimix dive (depending on size of dive)
Obviously back gas switches were out of the question , I had 8 other
trimixes to choose from, but all contained some N2.
Some unpleasantness occured when a long hose was swapped at the surface. My
tongue was sucked into the partial vacuum, but luckily the hose wall
yielded and i pulled my tongue free (now 6'' longer)
The deco plan was created on propietary software, but apart from the deep
stops placing and times looks similar to a traditional buhlman model with
the helium values changed. Deco ran 6 hours 40 mins...I surfaced exhausted
and suffered pulmonary toxicity for 3-4 days.
I have a deco plan analyser which can check plans created from even the
most comical dive software. When the interface is more user friendly (to
me!) I will send some details...you need to see it ! Any dive plan will
have its weakneses revealed both DCI/ICD related and oxtox and body work
load
Most planners generate deeper stops from the top down...this is just crap.
The free gas "miracle" dive planners need leaving well alone.
I am not claiming this as anything other than the deepest solo dive on
scuba, which happened to be (more importantly) the first without
significant DCI.
I appreciate this is a very brief message, if anyone is interested I can
send a detailed account.
cheers...Mark E
Sorry for nicking Brens job
