KONGSBERG EM 302 MULTIBEAM ECHOSOUNDER
The EM 302 is a hull-mounted 30-kilohertz multibeam echo-
sounder composed of two long transducer arrays mounted
in a T-shape on the hull of E/V Nautilus. The EM 302 can map
the seafloor in water depths from 10 to 7,000 meters (33 to
22,965 feet) at ship speeds up to 12 knots.
FREQUENCY. 30 kilohertz
DEPTH RANGE. 10–7,000 meters (33–22,966 feet)
PULSE FORMS. CW and FM chirp
ANGULAR RESOLUTION. 1° × 1°
APPROXIMATE SWATH WIDTH. 3–5 times water depth,
up to 8 kilometers (5 miles)
SOUNDINGS PER SWATH. Up to 423 in single swath mode,
864 in dual swath mode
APPROXIMATE GRID RESOLUTION. 1%–5% water depth
(e.g., 10–50 meters [33–164 feet] at 1,000 meters
[3,281 feet] depth)
KNUDSEN 3260 SUB-BOTTOM PROFILER
AND ECHOSOUNDER
The Knudsen 3260 is a sub-bottom echosounder mounted
inside the hull of E/V Nautilus. It operates at low frequencies
(3.5 and 15 kilohertz) so that emitted sound can penetrate
layers of sediment to about 100 meters below the surface.
OPERATING FREQUENCY. Dual frequency, 3.5 and
15 kilohertz
POWER. 4 kW on Channel 1 and up to 2 kW on Channel 2
RANGE. 50–5,000 meters (164–16,404 feet)
KONGSBERG SIMRAD EC150-3C TRANSDUCER
The Kongsberg Simrad EC150-3C 150 kilohertz is a hull-
mounted transducer that combines an acoustic Doppler
current profiler (ADCP) and an EK80 split-beam fisheries
sonar into one instrument. The ADCP measures the speed
and direction of currents underneath the ship, whereas the
split-beam echosounder maps features found within the
water column.
FREQUENCY. 150 kilohertz (130-170 kilohertz range)
DEPTH RANGE. <400 meters (1,312 feet)
BEAMWIDTH. 3° at 150 kilohertz
PULSE FORMS. CW or FM
ADCP NUMBER OF BEAMS. 4
ADCP DEPTH BIN CELL SIZE. 2-16 meters (6.5-52.5 feet)
ULTRA-SHORT BASELINE NAVIGATION SYSTEMS
SYSTEM. Sonardyne Ranger 2 with Lodestar
GyroUSBL transceiver deployed from the moonpool
for USBL tracking
DEPTH RANGE. Up to 7,000 meters (22,966 feet)
POSITIONING ACCURACY. 0.5% of slant range
OPERATIONAL COVERAGE. ±90°
OPERATING FREQUENCY. 19–34 kilohertz
TARGETS TRACKED. Hercules, Argus, and two additional
transponders are available. More targets can be tracked
with the addition of compatible Sonardyne transponders
ACOUSTIC SYSTEMS