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Pony bottle ascent schedule?

Discussion in 'Advanced Scuba' started by dstrout, Mar 30, 2010.

  1. RJP

    RJP Scuba Media & Publications

    # of Dives: 1,000 - 2,499
    Location: New Jersey
    13,460
    6,055
    In your assumptions you said you were within NDL. You can ascend directly - albeit slowly - directly to the surface.

    Do you have enough gas in your "no specific size mentioned" pony bottle to do the schedule you proposed?
     
  2. GrumpyOldGuy

    GrumpyOldGuy Solo Diver

    # of Dives: 200 - 499
    Location: West Texas/NH/CA
    4,579
    2,444
    The OP specifically stated he has a 30 cu ft full of air.
     
  3. RJP

    RJP Scuba Media & Publications

    # of Dives: 1,000 - 2,499
    Location: New Jersey
    13,460
    6,055
    Oops - thanks
     
  4. scubadada

    scubadada Diver Staff Member ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
    Location: Philadelphia and Boynton Beach
    14,449
    10,879
    Hey Dave,

    This is not complicated. Dive was within no decompression limits using 32% nitrox below usual MOD without toxicity and then run out of back gas. Make normal ascent to surface using the more than ample 30 cu ft pony. For me that would be a normal rate ascent to 15 feet and then a 3+ minute safety stop prior to surfacing. Anything more conservative would be to personal taste and would not likely hurt. I would not limit my diving for the rest of the day.

    I would crack the beer at the end of the day but would bag the cigar, personal taste again.

    Good diving, Craig
     
  5. RJP

    RJP Scuba Media & Publications

    # of Dives: 1,000 - 2,499
    Location: New Jersey
    13,460
    6,055
    Really?

    Inexplicably going OOG at 130' wouldn't cause you to want to take some time to stop and rethink... SOMETHING... before diving again?

    :cool2:
     
  6. Dr Wu

    Dr Wu Regular of the Pub

    # of Dives: I just don't log dives
    Location: The State Department adds pages to my Passport abo
    1,469
    60
    You went OOA with a mix most would consider a bit rich for the planned depth of your dive. Now you want a pony to save your ass and have no idea if you will survive.

    Sounds about right.
     
  7. gcbryan

    gcbryan One Bad Hombre

    # of Dives: 1,000 - 2,499
    Location: Seattle
    19,194
    14,250
    Yes, Really. Why stop diving just because "Neptune disrupted the first dive"?

    Sure, if you ran out of gas because of poor planning that's one thing but if a burst disc blew or a hose erupted if you have other gear why end the dive for the day?
     
  8. DaleC

    DaleC Solo Diver

    # of Dives: 500 - 999
    Location: Leftcoast of Canada
    4,981
    2,325
    Putting aside the 32% faux pas, if I went totally OOA on back gas at 130' within the NDL and had to bail to a pony I would ascend directly to my SS and due an extended stop there rather than at depth.

    My reasoning is that by using a pony you/I have demonstrated that our primary reliance for a second air source is the pony, not a buddy. Lingering at depth with that as my (now) only air source poses more risk (to me) than skipping the deep stops (which may or may not provide a reduced DCS risk).

    At those depths there is a difference between 21 and 28% though. Recently we did a wreck dive to 100' with my buddy on 32% and myself on 25% (long story). This resulted in him having an approx. 7 minute deco obligation and I a 19 minute deco obligation for the same depth/dive/duration.
     
  9. RJP

    RJP Scuba Media & Publications

    # of Dives: 1,000 - 2,499
    Location: New Jersey
    13,460
    6,055
    Well then, that's not "inexplicable" is it?

    :D
     
  10. Dr Wu

    Dr Wu Regular of the Pub

    # of Dives: I just don't log dives
    Location: The State Department adds pages to my Passport abo
    1,469
    60
    At least it is within the "not my fault" range.


    That has to count for something.
     

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