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| Daily Report from Anthony Johnson
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| Steady progress on OBS deployments. Swell is 3-4 m, winds are moderate. We are expecting the weather to deteriorate toward the end of the day, however, at the moment the visibility for MMO ops is good.
PIs met with Anthony Johnson and MMOs to discuss most recent document from LDEO OMO regarding the interpretation of the SARA and IHA documents. Anthony is preparing a summary (MGL0910_IHA_Analaysis.odt). In short, the current mitigation procedures are achievable.
At 1920 UTC we completed the deployment of the 64-element OBS array. All went smoothly and on schedule.
We are currently at the northeast corner of our array, making 2 Kts northward in preparation for launching the airguns. Visibility today, as it was yesterday, should allow clearing of the 160 dB radius for the 15 m tow depth.
1950 UTC: High pressure air on the main deck! A welcome announcement.
By mid-afternoon there is one gun firing on string 1. String 2 hits the water around 2230 UTC. The winds are picking up, steady at about 20 to 25 knots from the south, southwest. A low pressure system approaching. Following dinner there are three strings in the water. String 4 was launched first, then 3. Strings 1 and 2 are the last to go in; these two strings should be in good shape, having been used on previous legs. Strings 3 and 4 are new ones and there are kinks to be worked out. String 4 seems to be operating well after some initial drop outs. The command sequence was reinitialized and the guns reset. Appears to have fixed the problem. String 3 does not show that all guns are firing. It may be possible that they are, but the information is not returning to the ship. Gun 8, string 3 is assumed to be the source of the problem and is pulled back on board, shortly before 1900 PDT
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