EchoNIMBUS-MBES payload includes:

Cerulean Surveyor 240-16 MBES sensor head
Cerulean Bar30 depth/pressure sensor
Foldable mount with housing/fairing for MBES
Data cable with connector for SkyHub onboard computer
Transport case
Surveyor 240-16 is a 240 kHz multibeam echo sounder (MBES). It has a transmit beam approximately 4 degrees along track, 80 degrees cross track, and a 16-element receive array.

Surveyor 240-16 utilizes an angle-of-arrival estimation algorithm to measure cross track location of specific acoustic reflectors well in excess of the accuracy achievable with conventional beam-forming techniques. Thus, although the effective cross track beam width with conventional beam forming is about 7 degrees, Surveyor can resolve angle of arrival to less than one degree.

Depending on the range and acoustic properties of the bottom, Surveyor typically identifies 10-15 acoustic targets across track within a swath width of 80 degrees. The position and depth of these targets are then accurately calculated by range and angle of arrival.

Surveyor includes a built-in IMU for pitch and roll. Heading and coordinates for data geotagging are coming from the drone.