Page 563 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

562
CHAPTER 21 Practical Applications
21.4.5 Underwater environment of ports ......................................................................... 591
21.4.6 Navigation accessories........................................................................................ 592 21.4.6.1 Imagingsonar..............................................................................................592 21.4.6.2 Acoustic positioning......................................................................................592 21.4.6.3 Difficulties involved with sonar and acoustic positioning.................................593
21.4.7 Techniques for accomplishing port security tasks .................................................. 595 21.4.7.1 Hullsearches...............................................................................................595 21.4.7.2 Under-vesselbottomsearches......................................................................596 21.4.7.3 Pier/mooring/anchor searches.......................................................................596
21.4.8 Development of TTPs for port security .................................................................. 596
21.4.9 Results of procedure testing by sizes.................................................................... 597
21.4.10 Inland...............................................................................................................598
21.4.11 Offshore............................................................................................................599
21.5 Conclusion .................................................................................................................................599
21.1 Explosive ordnance disposal and mine countermeasures
As discussed below, the development of mine countermeasure (MCM) vehicles has radically chang-
ed direction, driven by the threat of increased numbers (versus sophistication).
21.1.1 Background
A sea mine’s purpose in warfare is a basic “access denial” function for disrupting an enemy’s sea navigation capability. If an amphibious landing is anticipated, a clear path to the beach requires clearing of sea mines to allow the vessel an access path. The same concept applies to shipping, since a harbor or navigation channel can be immediately shut down with any threat of sea mine presence.
Sea mining has not changed considerably since the days of the American Civil War, when Admiral Farragut declared “Damn the torpedoes” (older term for sea mines). Sea mines are still, to this day, extremely difficult to locate and neutralize. However, technology is allowing for enhanced location/identification capabilities as well as safer and more environmentally friendly means of neutralizing these sea mines.
Accordingly, the development of remotely operated vehicles (ROVs) for use in explosive ord- nance disposal (EOD) and MCM missions is a military mission. This was both a blessing and a curse. The need for such systems was there, as was the funding, but the design specifications were such that the vehicles became large and expensive. The complexity of early MCM vehicles also lengthened their time of development. For example, the US Navy’s mine neutralization system (MNS), AN/SLQ-48(V), took nearly two decades to move from concept to operational status (Figure 21.1). Today there are approximately 60 in the field.
The United States was not the only country building MCM vehicles. ECA of France had the workhorse of the early MCM category, the PAP 104, which hugged the bottom using a drag weight. Today, ECA has fielded approximately 450 PAP vehicles, 120 of which are the new PAP Mark 5 systems (Figure 21.2).