Ouroboros Mod1 Report
By NAD
I wrote the report by memory so it is possible to I may have forgotten something. The skills are those reported in the manual, it could be there are some differences on the sequences. We did the disinfecting work at the end of the week. After every dive, we just washed mouthpiece and hoses.
However, Phil’s main point was “I don’t care about what you already know; we have to do everything, same for theory!” This is the kind of course and instructor I like. Masochist? Maybe, but at the end of the course I felt OK to use the Rebreather by myself. For some years now, I’ve been diving the VR3 so I’m comfortable with the layout and system, this helped me with the rebreather.
Monday Dive #1 - 65 min - In-water checks for bubbles
- Buoyancy Check
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
To understand the manual injection dynamics of the Rebreather with limited electronic information.
To avoid confusion at this early stage, which a detailed use of the electronics would generate.
To understand the affect of minimum loop volume.
To define the student weighting requirement.
Ignore the HUD.
Use backup display as primary PO2 monitoring with the primary display as confirmation.
Disable the ADV and manually inject oxygen and diluent.
Set the automatic setpoint to 0.7 and maintain the Rebreather manually at 1.0 PO2.
Monitor the PO2 every minute.
Tuesday Dive #2 - 65 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
To understand the manual injection dynamics of the Rebreather with limited electronic information.
To avoid confusion at this early stage, which a detailed use of the electronics would generate.
To understand the affect of minimum loop volume.
To define the student weighting requirement.
Ignore the HUD.
Use backup display as primary PO2 monitoring with the primary display as confirmation.
Disable the ADV and manually inject oxygen and diluent.
Set the automatic setpoint to 0.7 and maintain the Rebreather manually at 1.0 PO2.
Monitor the PO2 every minute.
To confirm accuracy of oxygen sensors.
With the automatic oxygen control isolated using the shutoff valve, manually flush with diluent using the Manual bypass until the PO2 on the displays equals the PO2 of the diluent at the current depth.
On completion of the drill, activate the automatic oxygen control.
With the loss of all primary and backup displays the HUD and main electronics will still function maintaining the PO2.
Remove all displays, except the HUD from vision.
Maintain PO2 manually on bottom and during a short ascent.
Dive #3 - 67 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
To understand the manual injection dynamics of the Rebreather with limited electronic information.
To avoid confusion at this early stage, which a detailed use of the electronics would generate.
To understand the affect of minimum loop volume.
To define the student weighting requirement.
Ignore the HUD.
Use backup display as primary PO2 monitoring with the primary display as confirmation.
Disable the ADV and manually inject oxygen and diluent.
Set the automatic setpoint to 0.7 and maintain the Rebreather manually at 1.0 PO2.
Monitor the PO2 every minute.
To show the small rise in PO2 which may occur during an oxygen shutdown, due to small-bore pipework.
At a depth of around 10m with stable PO2 readings.
Close the oxygen cylinder valve and push the manual oxygen addition until there is no gas left in the line.
Monitor the small rise in PO2.
- Selection of alternative setpoint and automatic setpoint control.
To be able to change the setpoint during a dive.
To understand the affects on buoyancy and loop volume when using the automatic oxygen addition system.
Start at 0.7 at the surface.
Upon reaching the target depth switch to 1.2 PO2.
During an ascent, at approximately 6m switch back to 0.7 PO2.
Wednesday Dive #4 - 66 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
To understand the manual injection dynamics of the Rebreather with limited electronic information.
To avoid confusion at this early stage, which a detailed use of the electronics would generate.
To understand the affect of minimum loop volume.
To define the student weighting requirement.
Ignore the HUD.
Use backup display as primary PO2 monitoring with the primary display as confirmation.
Disable the ADV and manually inject oxygen and diluent.
Set the automatic setpoint to 0.7 and maintain the Rebreather manually at 1.0 PO2.
Monitor the PO2 every minute.
Multi tasking buoyancy control with PO2 switch.
To instil that Rebreather rapid ascent can lead to PO2 and buoyancy control problems.
I was supposed to disable the ADV after leaving the max depth.
Ascend and maintain a safety stop at 4.5m.
With the loss of all primary and backup displays the HUD and main electronics will still function.
With just the HUD, generate a max of 5 minute deco penalty and conduct it with the use of the HUD.
Dive #5 - 70 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
To understand the manual injection dynamics of the Rebreather with limited electronic information.
To avoid confusion at this early stage, which a detailed use of the electronics would generate.
To understand the affect of minimum loop volume.
To define the student weighting requirement.
Ignore the HUD.
Use backup display as primary PO2 monitoring with the primary display as confirmation.
Disable the ADV and manually inject oxygen and diluent.
Set the automatic setpoint to 0.7 and maintain the Rebreather manually at 1.0 PO2.
Monitor the PO2 every minute.
To simulate a temporary flood.
Move to an upright position.
If possible locate a handhold on something on the bottom.
Add diluent until the exhale counterlung over-pressurises.
Water is drained from the exhale counterlung.
Thursday Dive #6 - 80 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
- Diluent and O2 Automatic
- Hypoxic Drill
This assumes the PO2 in the loop is less than 0.21.
This assumes the solenoid or manual injection has failed.
Visual and tactile alarms will have been activated well before this can occur.
To maintain buoyancy and elevate the PO2.
Exhale, add oxygen and breathe.
The ADV and oxygen addition will both add oxygen rich gas.
- Maintaining PO2 Between Deco Stops
To compensate for small drops in PO2 between deco stops.
This assists the automatic oxygen addition system and assures accuracy of PO2 tracking during manual control.
Prior to moving to the next stop.
Exhale, add oxygen and then move up in 3m increment.
Take some breaths and then correct as required.
Dive #7 - 63 min - In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
- Diluent and O2 Automatic
- Metabolic Rate
This drill assumes the failure of all electronic displays.
Set O2 controller to 1.0 PO2.
Swim at a moderate pace and note injection rate.
Switch controller to 0.7 PO2.
Remove all displays from view.
Keep swimming maintaining the PO2 manually using the known injection rate and buoyancy shifts to loop volume and hence PO2.
This assumes the PO2 in the loop is less than 0.21.
This assumes the O2 and dil supply have failed.
This would be indicated by low HP alarms and a low PO2 warning.
OC bailout.
Manually or automatically add oxygen.
If no more O2 is available ascend on OC.
Dive #8 - 62 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
- Diluent and O2 Automatic
- Hyperoxic Drill
This assumes the PO2 in the loop is greater than 1.6.
The solenoid or/ and manual O2 addition is jammed.
Isolate the O2 cylinder valve.
Isolate the solenoid shutoff.
Switch to OC.
Add diluent using either the manual addition or the bailout reg until the PO2 is safe to breathe.
Go back onto Rebreather.
Open the cylinder valve and close it quickly.
If no additional O2 is added then the solenoid is faulty and the unit can be dived with manual O2 addition.
If O2 still enters the loop the unit must be dived adding O2 by opening and closing the cylinder valve for 1 second intervals, as required.
This assumes the loop is intact but unbreathable (High CO2) and it is unsafe to flush the CO2 as would normally be the case.
OC bailout.
Select OC on the Primary display, this will disable the O2 injection.
Disable the ADV.
Ascend slowly, eventually vent small amounts by partially and quickly opening the mouthpiece.
Friday Dive #9 - 61 min- In-water checks for bubbles
- OC Bailout
At the surface and at the target depth, confirm O/C bailout is working.
Confirm PO2 on displays prior to switching back to the Rebreather.
- Diluent and O2 Automatic
- Cell Disabling
If the connection between the centre section and the electronics POD becomes faulty and hence the PO2 on the primary cannot be relied upon, you can disable all the O2 sensors on the primary and turn the rebreather into a manual control, fixed PO2 deco rebreather.
After confirmation on backup display with a diluent flush, disable all three O2 cells.
Confirm fixed setpoint in GAS menu.
Operate Rebreather using manual O2 addition and backup display.
Failure of O2 supply.
Add diluent to maintain a breathable PO2.
Use on board and/ or OC gas as appropriate.
Ah, I almost forgot - every dive day was followed by a dinner night,
2/3 elephants every one.
Cheers
Nad
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