BC Shipping News, Andrew Weir-Jones, May 2014
Do you recall a time when the only way to measure the draft of a vessel was to stare at the draft marks on a cold and windy night, or to go alongside in a dingy in choppy water? Now there is a much more accurate and convenient alternative.
Reliable and repeatable draft data can be displayed on the bridge irrespective of the conditions at the berth or in the anchorage. ADIS™, the Automated Draft
Indicator System, is not only much more accurate and convenient than the traditional use of draft marks, but it is far less intrusive and requires much less maintenance than pressure-based systems located inside the hull below the waterline.
ADIS™ calculates the draft and freeboard based upon the distance from the transceivers to the mean water surface. Unlike pressure-based systems, there is no need to correct for water density and temperature. ADIS™ provides a direct reading of the water plane position relative to fixed points on the hull — fore and aft, port and starboard, and amidships if there are concerns about hogging or sagging. And all without any hull penetrations above or below the waterline.
The Automated Draft Indicator System - more accurate, more convenient; less intrusive, less maintenance...
The through-hull penetrations below the waterline required for pressure-based draft monitoring systems can be managed and maintained, albeit with a degree of difficulty and cost. However, a “dry” option exists, and most mariners lean towards ‘no through hull penetrations’. In addition, sea creatures make the pressure ports home, compromising the functionality of the transducers, rendering the pressure-based system’s reliability ‘questionable’, and necessitating maintenance in dry dock.
ADIS™ was developed with the assistance of the British Columbia Ferry Corporation in 1995. Since then, it has provided hundreds of millions of realtime draft measurements on the West Coast. It has become the ‘go-to piece of equipment’ for operators and regulatory agencies in Alaska, British Columbia and
Washington State when there is a need to confirm that passenger vessels are operating safely and within design parameters. The tangible results operators obtain from their ADIS™ installations are:
Continuous and accurate draft data displayed in real time on the bridge and elsewhere.
Time-stamped, hard-copy draft readingsready for insertion into the log books.
Ultra-reliable, high-resolution displays.
Over 50,000 hours MTBF.
Ease of maintenance.
Immediate-issue resolution with no debate about the actual draft orfreeboard.
The original version of ADIS™ was very reliable and met the originally defined needs of operators. However, recent studies in Europe and elsewhere have demonstrated that properly trimmed vessels, running either in ballast or loaded, operate more efficiently — up to a five per cent fuel savings — and onsequently have less impact on the environment than non-trimmed vessels. ADIS™ is capable of providing accurate draft measurements to better than 10 mm, critical, considering the benefits resulting from reduced fuel consumption and better sea keeping.
The ability to trim a vessel accurately and consistently is of great value when optimizing fuel consumption or maximizing speed. ADIS™ can provide real-time water plane data to ballast control systems to minimize fuel consumption by allowing the control system to react to current trim and sea-state conditions. All this is what ADIS™ currently does for users including major ferry fleet operators and the U.S. Navy. Now, ADIS™ has been updated — the existing features
retained and new ones added -- to make it even more useful for vessel operators. In addition to the capabilities described above, the system now incorporates the following features:
Wi-Fi, cellular and satellite communications for data delivery to a variety of end users; owners masters, operations, HS & E, personnel, etc.
Remote system health monitoring and diagnostics on a 24/7 basis for pre-emptive planned maintenance or for immediate service of faulty components.
An automatic software download/updates option. Irrespective of the vessel’s location, the latest software updates can be installed at the next port-of-call if the operator selects this feature.
Secure Android/iPhone applications for remote real-time monitoring of the vessel’s draft away from the bridge or even away from the vessel.
Streamlined installation procedure.
Easily replaceable ‘service’ modules. In the unlikely event of a component failure, and when there is not a spare on board, a replacement can be shipped to the next port-of-call.
Extensive data logging and reporting functionality.
Windows-based, hi-resolution bridge and deck displays.
Expanded user features.
Expanded display features.
By releasing the second generation ADIS™ and the Version 7 software, a world-class product is available which preserves the previous version’s reliability, adds a number of user-requested features, and, when using shipyard electricians to install the system, the remote health monitoring and diagnostics feature eliminates the need for factory personnel to be present. The system integrity can be remotely verified, the installers assisted if necessary, and any software changes downloaded.
With the original version of ADIS™, there was the potential inconvenience to owners that factory personnel had to perform routine software updates. Now, the new system simply ‘checks in’ when it detects cellular coverage; ADIS™ then automatically downloads, updates and reports that they are available for installation.
An alternative procedure allows software updates to be installed using a local Ethernet connection. The potential for optimizing trim in real time and maximizing fuel efficiency is not the only economic benefit that ADIS™ offers. The difference between knowing that the keel will clear the sill or threshold of a lock by 10 cms, and hoping that it will clear it by 25 cms can mean two thousand tonnes of additional cargo and profit on a round trip. On this basis, ADIS™ offers an immediate and very direct benefit to vessels which have to transit locks or operate in shoaly waters. Today it is essential to operate safely and efficiently at all times. Acceptable margins of error are diminishing, and owners/operators are likely to be held accountable for what once would have been considered as ‘accidents’ by regulators or the public. In these situations, ADIS™ provides information which not only demonstrates a responsible attitude but saves money too.