In the Spring of 2012, ASE designed and commissioned a 22-foot marine
survey vessel that will handle every possible type of bathymetric survey to
U.S. Army Corps standards. Christened
the Abraham Lincoln to honor the historic surveyor from our home state, the
boat is fully equipped to handle Multi-Beam Echosounding; Single-Beam
Echosounding, Sub-Bottom Profiling and Side Scan Sonar work. The boat was designed by Coventine Fidis, the
CEO of American Surveying & Engineering, to be the perfect tool for use on
any survey described in the U.S. Army Corps of Engineers manuals on marine
surveying. The boat was built by
Scully’s Custom Aluminum Boats in Morgan City, Louisiana, and it joins our
existing fleet of boats, including the 32-foot George Washington (which
we named in commemoration of another noted surveyor).
We designed the Abraham
Lincoln to accommodate all possible survey uses from stern to bow. Horizontal and vertical
offsets are measured relative to the longitudinal Center of Gravity (LCG) of the
survey vessel. Initial loading of the vessel establishes a waterline marked in
four places on the hull of the vessel.
The vessel is blocked and leveled in two planes; along the centerline
(keel) of the vessel (Y) parallel to the waterline and athwrartship to the
centerline (port to starboard). The LCG is
calculated and furnished by the manufacturer of the vessel and is referenced as
0.00, 0.00, 0.00 (forward, starboard, up) in a vessel cartesian coordinate
system. All vessel control points are
referenced conventional survey methods using a total station from three (3)
distinct survey points surrounding the vessel.
A least squares adjustment is performed on all of the control and the
adjusted coordinates will be used to develop the offsets to be entered into the
The Abraham Lincoln is packed with specialized surveying
instruments and equipment.
R2Sonic 2022 High-resolution multi-beam
Trimble Marine SPS852
Dual Frequency (GLONASS enabled) Real
(RTK) GPS positioning and heading system
Teledyne DMS-10 Motion
Valeport SV Sound velocity probe
Valeport SVP sound velocity profiler
Frequency GPS Real Time Kinematic positioning
base and rover receivers with RTK radio data link
This built-in equipment can be supplemented with our Sub-Bottom
Profiling equipment and our Side Scan Sonar equipment without sacrificing any
Accuracy and Equipment Precision
Horizontal positioning for depth measurements uses
electronic positioning modes or systems, or hybrid combinations of instrumental
and electronic data measurement and recording systems to measure, adjust,
correlate, print, plot, and record horizontal and vertical observations. USACE hydrographic surveying requirements per
EM 1110-2-1003 Engineering and Design – Hydrographic Surveying, are followed.
R2Sonic 2022 high resolution multi-beam sonar unit is port
side mounted on R/V A Lincoln and
interfaced to R2Sonic sonar
interface module (SIM). The 2022 has on the fly selectable frequencies
from 200 to 400 kHz, 1° by 1° beam width, True Range Resolution of 1.25
cm, 500m range and on the fly selectable swath coverage of 10° to 160°.
Teledyne DMS-10 Motion
Reference Unit (MRU)
This instrument provides measurements of attitude; namely heave, pitch, roll measurements. The DMS-10 is capable of measuring to the
nearest 0.10 degree RMS. It has a
maximum range of 60 degrees, a bandwidth of 0 to 30 Hz and a depth rating of
Data Processing Computer
computer is a Dell Precision M660 Workstation Laptop.
from the sonar is corrected by the Teledyne MRU and is interfaced to
computer on the network with HySweep survey program.
(SV) and (SVP) Sound Velocity Probe and Profiler
Sound Velocimeter is attached
to the head of the multi-beam echosounder and constantly monitors the speed of
sound in the hydrosphere at the head of the sounder. In addition a Valeport Sound Velocity
Profiler is used to make sound velocity casts throughout the survey area as
required. Sound velocity is measured in the survey area to the
required depth. Every foot is a graphed profile of the speed of sound through
the water column and used to correct the survey data.