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In message <ECS9705021256A@li*.ac*.uk*>, Steve Millard
<ec96@li*.ac*.uk*> writes
> BILL STONE CIS-LUNAR MK.5
>
>For his 2nd formal presentation Bill Stone began by announcing WAKULLA 2 -
Oct.
>1 1997 to Jan 30 1998. The U S Deep Cave Team (USDCT) is looking for divers
to
>assist with this expedition with a range of skill levels, including rebreather
>diver, support diver, programmers and chamber operators.
Steve
Thanks for posting the proceedings.
I have a few observations....
1) I am curious as to the request for assistance for such a high level
project. For this kind of 'serious' work I would expect an exclusive
group of finely tuned, very fit and focused indiduals. To throw it open
in this way seems a little desparate.
>
>An overview was first given of the Wakulla Springs cave and the 1987 WAKULLA 1
>expedition. The development of a decompression habitat was reviewed which
would
>enable up to 6 divers to decompress for 10 to 15 hours in warm dry conditions
>from depths between 70' and the surface. Some of the early sport dives in the
>USA using mixed gases were shown where divers wore 4 or 5 tanks on their body
>and had a further 4 to 5 tanks strapped to their scooters. A short 3 minute
>video clip was shown of Rob Parker, Wes Skyles and Brad Solomon penetrating
>Wakulla against a 1+1/2 knot current & returning to the habitat.
How times change?
>
>Bill then spent some time reviewing the theory of failure analysis and
>reliability as applied to existing closed circuit systems (USN Mk15 & Mk16),
>independent quad tanks, manifolded twin tanks and redundant closed circuit
>systems (the Cis-Lunar Mk.1 to Mk.5).
>
>An overview of the principal features of the Mk.5 was then given (for those
who
>missed the workshop). Additional features which were covered were :
>
> Head up display
>
> Deco LED - has 3 states.Green = no problem,
> Flashing green = deco stop reached,
> Red = too shallow
What is this info based upon - tables/algorithm/past data?
>
> Oxygen LED - has 5 states Green = OK
> Yellow = too high ppO2
> Flashing yellow = too low ppO2
> Red = above 1.6 ppO2
> Flashing red = hypoxic within 5 mins
I trust the 'hypoxic within 5 minutes' is workload/scrubber state
related?
>
> System LED has 2 states Green = OK
> Red = Check primary display to
identify
> system problem
Sounds like this system takes more time checking than would be
safe/usable for survey work?
>
>The Mk.5 is said to have a 6 hour capability at any depth for a typical diver
>swimming at 20m/min. At rest a duration of 10 hours would be expected. It
has
>a weight of 55 lb. and a volume less than twin 80s. It can be fully
integrated
>with a Morgan full face mask incorporating comms. The gas efficiency against
an
>open circuit set is typically 56:1. On board cylinders were 400 cu.ft
>(oxygen)and 240 cu.ft.(diluent) in size. The total number of hours spent of
>Cis-Lunar rebreathers is in excess of 2500 hours.
Hmmmm.... not sure how 400 cu ft of O2 and 240 cu ft of diluent would
look in cylinders ( a rough guess is five 80 cu ft's plus three 80 cu
ft's for diluent) this does not seem compact?
>
>Bill discussed the original plans to include a CO2 sensor & alarm feature &
>concluded that with existing technology it was not possible to include an
>effective CO2 detection capability into the Mk.5 and that this feature had
>therefore been dropped.
Drager isist that reliable technology is not availble to incorporate
PpO2 control let alone CO2.
> The Mk.5 does however not only record the total time
>spent using the scrubber since it was last refreshed, it calculates the CO2
that
>should have been produced from the O2 consumption (assuming no gas loss
through
>leakage, mask clearing etc.) and incorporates a warning if the scrubber is
>reaching the limit of its expected duration.
How does this allow for ascents?
>
>The final part of the talk focused on the plans for 'Wakulla 2', Bill Stone's
>next planned expedition into Wakulla Springs cave system some 10 years after
the
>original 'Wakulla 1' expedition.
>
>No mention was made of the on-going Woodville Karst Plains Project (WKPP)
>explorations over the past 10 years, headed by George Irvine and his team of
>lead divers & support crew. WKPP are presently exploring Wakulla Springs
using
>radically different techniques, philosophy and rebreather to that proposed by
>Bill Stone.
Hmmmm..... I would suggest that the techniques are different based upon
experience - WKPP always said there would come a point where they would
have to use rebreathers - now they are doing.
>
>
>The Wakulla 2 expedition is expected to cost around 1.3 million $US with the
>funding all coming from private sponsors. The stated objectives are :
>
> To explore up to 6 km from the entrance,
WKPP are already close.
>
> To produce a 3D map of the cave system, integrated to surface features
>with an accuracy of 5cm
WKPP are already producing this.
>
> To leave no impact on the park at the end of the expedition
WKPP already operate ana weekly basis with little or no impact.
>
>The expedition has developed DPVs (scooters) with a 15 km range which are
about
>2 x the size of an Aquazepp. The DPVs use NiMH batteries and the diver will
>effectively be diving with 3 Mk.5 rebreathers (one on their back and 2
attached
>to the DPV), giving a possible 18 hour capability. No staging of open circuit
>tanks is planned. One type of DPV incorporates a backup DPV with a 6 km
range.
> Another model incorporates an automated digital wall mapper in the DPV nose.
>The mapping system works by using some 64 sonar sensors arrayed in a helical
>pattern around the nose linked to a 3D inertial guidance system which
>automatically gives the x,y,z position co-ordinates of the DPV together with
the
>pitch, roll and yaw aspects. Scanning position data at a rate of 50 times a
>second, the entire tunnel cross-section will be automatically mapped to a 5 cm
>accuracy. As a backup to correct some known drift problems associated with
>inertial guidance systems (at worst a drift of 1m in 200m-300m might occur), a
>sequence of 'drop pods' with flashing LED's will be positioned at regular
>intervals along the tunnel system. The light from the LED's will
automatically
>be detected by the DPV system & any inertial drift corrected. Up to 8 Gb of
data
>can be stored by each DPV.
OK,OK - now we are on Mars! - All joking apart, for what possible reason
is this technological 'leviathan' way of cracking a relativly simple nut
with a hugely complicated sledghammer all heading towards?. From the
info that has been posted I would be worried about the most tuned team
in the world doing this let alone somebody who is oulicaly asking for
helpers!
>
>The expedition divers are not planning to carry out their dives as in previous
>'bounce dives' excursions from the surface with in-water or habitat
>decompression at the end of each dive. Instead it is planned that lead divers
4
>of 2x2 man teams will remain in saturation in a surface hyperbaric habitat
>maintained at a pressure of 55m-65m. The habitat weighs some 100,000 lb. and
>will be transported into the entrance region in sections. The habitat will be
>located on a floating barge and divers will be transferred to a depth of 55m
in
>a transfer bell.
>
>One of the principal planned objectives of the expedition is to produce a
>virtual environment theatre so that the public can experience what it is like
to
>explore Wakulla Springs. Visitors will wear 'crystal eyes' LCD shutter
glasses
>and will be able to experience a full 3D virtual reality show.
Send a donation to WKPP - see it in real video footage!!!!
>In addition the
>3D map will be available for scientific aquifer studies to enable tracking of
>pollutants through the cave system to be modelled. In fact Bill stated that
>although he hoped that the known limits of the Wakulla Springs system would be
>significantly extended, even if no new cave were actually reached but the 3D
>mapping system worked as planned on the existing known cave then the whole
>expedition would be considered a 100% success.
Sounds like a cop out clause to me - why prove an experimental cave
mapping system in a situation that involves lots of 'wannabees' in deep
cave?. The cave is already being mapped in fine fashion.
>
>The talk concluded with a short computer animation showing a visualisation of
>the cave system explored in the original 1987 Wakulla 1 expedition. A 3D
model
>was shown which could be rotated, panned and zoomed to display features of the
>cave system. The Wakulla 2 expedition was expected to involve between 75-100
>people for periods of 2 weeks or more and an invitation was extended for those
>interested to contact the project.
SNIP>>>>>>>>>>>>>>>>
Steve thanks for the info.
Regards
Chris Hellas e-mail - chris@de*.de*.co*.uk*
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