Slocum Ballasting Checklist¶

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Mission:  ________________________________   Glider S/N:  _____________

Engineer:  ________________________________   Date:  ________________

1. Before Powering Up¶

• Glider closed with a proper vacuum — ≥ 6 in Hg shallow / ≥ 7 in Hg deep
• PEEK MS plug torqued to 15 in-lb
• Ballast tank filled, large enough to fully submerge the glider, and a way to lift it in/out confirmed

2. Setting Ballast Mode¶

• Power the glider (external 15 VDC or green go-plug)
• If in PicoDOS: app to start GliderDOS
• Ctrl-C to gain control
• callback 30
• lab_mode on
• ballast — confirm pump/pitch vernier at 0 and bladder deflated
• Science sensors live for tank density (loadmission sci_on.mi or the c_science_* puts)

3. Immersing the Glider¶

• Wings fitted (or taped to the aft hull if the tank is too small)
• All trapped air purged from nose cone and aft cover
• HD (deep) pump: extra care taken to clear entrapped air

4. Weight Adjustment¶

• Tank temperature/conductivity read and density calculated
• Target (deployment) water temperature and density entered in the Ballast Adjustment Spreadsheet
• Weight added/removed (external or internal) toward the spreadsheet's target
• If too heavy: spring-scale check at fore/aft end caps done before removing weight
• Neutral buoyancy confirmed in the tank at the reference state (0 cc pump / 0 in pitch / 0° roll / bladder deflated)

5. H-Moment¶

• H-moment measured (report ++ m_pitch m_battpos, or wing-mass roll-response method) — only needed on initial ballast or after a configuration change
• H-moment within 4–7 mm (5–6 mm ideal; toward 7 mm if running a thruster)
• Roll weights adjusted as needed and re-measured

6. Close-Out¶

• Exit ballast / lab_mode; confirm glider is back on a normal mission before deployment
• Glider re-sealed with proper vacuum on the final close (not just a working ballast open)
• Weight/H-moment changes logged for this glider

Notes:

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