by T. Keith Marshall
ARPA is an acronym for Automatic Radar Plotting Aid. It is a sophisticated piece of navigation equipment found on the bridge of most ocean-going vessels that combines a traditional radar display with a computer driven plotting device. After either manual or automatic acquisition of radar targets the ARPA will compute and display a variety of information useful to the navigator in making collision avoidance and navigational decisions. It is indispensable when navigating in areas of high traffic density such as the Straits of Mollucca or the English Channel, especially in restricted visibility.
All ARPA models display basic collision avoidance data: CPA (closest point of approach), TCPA (time to CPA), range (distance) and bearing (direction) to the target of interest, and target course and speed. The most advanced models will allow a nautical chart of the area being transited to be electronically overlayed upon the radar display so that by looking at one screen the navigator can see where he is with respect to the charted channel as well as view stationary and moving targets that may pose a threat to his planned navigation. The designers of these systems often include far more features in them than most operators will ever use.
Though some operators will explore the most advanced features of their ship's ARPA, few will use them on a regular basis and many more are content with a mastery of only the basics. With a properly set up ARPA at his disposal and competent and informed use of its features, the navigator should be able to avoid virtually all collisions. However, we all know that collisions continue to occur.
During a post-collision investigation, inquiry into how the ARPA was set up and being operated may reveal negligence by the operator that will assist your client in recovering from what is almost always a mutual fault loss. Each percentage point of fault you build against the other vessel will assist your client in loss recovery when it comes time for the court to apportion damages. United States v. Reliable Transfer Co., 421 U.S. 397, 1975 A.M.C. 541 (1975).
In some instances it may be possible to go one step further. When an owner faces losses in excess of the value of his post-collision hull, he may seek to limit his liability pursuant to the Limitation of Liability Act, 46 U.S.C. 181 et. seq. One way to defeat the owner's petition is to prove that the vessel was, with the owner's privity and knowledge, unseaworthy at the time of collision and that the unseaworthiness was the proximate cause of the collision. 46 U.S.C. 183(a). When an owner crews his vessel with persons not up to the standards of their calling, he has not sent her to sea in a seaworthy condition and limitation may be denied. Tug Ocean Prince, Inc. v. United States, 584 F.2d 1151 (2d Cir.1979), cert. denied, 440 U.S. 959 (1979). Gross negligence in use of the ARPA may be grounds for a claimant to challenge limitation on the basis of unseaworthiness.
That was precisely the issue before the court in Complaint of Waterstand Marine, 1991 A.M.C. 1784 (E.D. Pa. 1988). There the owner of the SEAPRIDE II had furnished her with a Master not fully trained in the use of ARPA. As the vessel made its way down the Delaware River in fog under direction and control of a compulsory pilot, it allided with a tower supporting high-voltage transmission wires across the river. When the vessel's owner petitioned for limitation of liability the utility company that owned the tower challenged the petition based on unseaworthiness due to the vessel carrying a Master and Pilot untrained in the use of ARPA. Limitation was denied. 1991 A.M.C. at 1800-01.
The owner had equipped his vessel with an ARPA as required by Chapter V Regulation 12 of the Treaty on Safety of Life at Sea (SOLAS)(codified under U.S. law at 33 U.S.C. 1223(a)(3); 33 C.F.R. 164.38 App. A, 3.4.6). The court held that mere equipping of the vessel with ARPA was insufficient. The owner had a nondelegable duty to also provide his vessel with persons trained in ARPA operation. 1991 A.M.C. at 1799. Failure to do so rendered the vessel unseaworthy. The unseaworthiness was imputed to the shipowner and found to be within his privity and knowledge because of his failure to select a proper crew at commencement of the voyage. 1991 A.M.C. at 1800.
While almost all vessels are properly equipped as a result of vessel inspection laws, there is no similar requirement that each mariner prove his or her competence before joining a vessel. Owners often hire third-world citizens untrained in the use of modern electronic equipment through hiring agencies totally sight unseen. Investigation into the hiring practices used and the actual skill of the mariner involved in a collision may yield ammunition for challenging a limitation petition based on crew unseaworthiness. In extreme cases negligent ARPA operation may be so gross that it is tantamount to unseaworthiness within the privity and knowledge of the vessel owner.
Owners would be well advised to ensure that they furnish their vessels with competent, qualified, and fully trained personnel to operate this invaluable electronic navigation and collision avoidance tool. A consultant well versed in ARPA operation can assist the attorney in detecting weaknesses in this area. Conversely, where opposing counsel is challenging your vessel's operation of the ARPA or any other navigation equipment, a knowledgeable consultant may be able to assist in proving that the equipment was being operated properly. In a perfect world there would be no collision between vessels, but even in this modern electronic age it seems certain that they will continue to occur.
Author is a USCG-licensed Master Mariner sailing with District I MEBA and affiliated with MEC as consultant. He is a 1994 graduate of Tulane Law School and resides in Charleston and New Orleans.
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