USS Hawkbill, Pearl Harbor, Hawaii

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USS Hawkbill, Pearl Harbor, Hawaii
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• 12 kHz Sidescan Swath Bathymetry Sonar
• 2.5-6.5 kHz Swept Frequency Subbottom Profiler
• Gravimeter

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Unanticipated Findings - Mapping the Ice
Canopy SCAMP was designed to send sound
downwards, but we observed coherent patterns in
outgoing portion of the data
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PORT
SCAMP LOOKS UPWARD
STBD
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SHADOW ZONE
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• Conditions Controlling Ice Canopy Maps
• Water Depth (300-5500 m)
• Submarine Depth Below Surface (220 ft, 440 ft
  and 750 ft)

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Water Depth 300 1000 meters Submarine
Depth 220 ft below surface
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In shallowest areas, swath width is too narrow
due to return from bottom
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Water Depth 1000 4000 m Submarine Depth 750
ft below surface
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When submarine is 750 ft deep, the SN isnt
sufficient to depict structure of the ice canopy
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Water Depth 300 1000 meters (tend to be
deeper) Submarine Depth 440 ft below
surface (220 ft on margin)
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4-5 km wide swath shows lineations we think are
keel locations
Parallel orientations regardless of sub heading
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• We Find the Optimal Conditions for a 12kHz sonar
• Water Depth (gt1000 m)
• Submarine Depth Below Surface 220 - 440 ft
• Produces and Ice Canopy Swath of 4-6 km!

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SCAMP Magnitude
Phase
Coherent Phase