3-15
Tow Vehicle Deployment
Therefore only reflection coefficient measurements made when the sea floor slope is within
3.5 degrees of horizontal will be accurate within 10% (1 dB).
The attitude of the tow vehicle with respect to the horizontal plane must meet the -1 dB
criteria described above for sediment classification surveys. Rough sea conditions will tend
to move the vehicle up and down vertically causing oscillations in the images. DISCOVER
3200SB has a swell filter that will help reduce the heave effect on the record. Refer to the
"DISCOVER 3200SB Sub-Bottom Software User's Manual" for details. For sediment
classification, the tow fish pulses must be calibrated by the end user. This calibration
procedure is described in the software manual.