Draft Functional Requirements
for a

Potential New Generation Standard UNOLS
Small Diameter
Electro-Mechanical (EM)
or
Electro-Optical-Mechanical (EOM) Cable

Draft Final Report Available For Review and Comment
(Click the above link for the full report and functional requirements - 629 KB PDF file)

Email comments to: office@unols.org

Purpose and Executive Summary

Why are we doing this?

Oceanographic wires and cables are a component of the scientific infrastructure on board research vessels that are often taken for granted, until they fail or prove to be inadequate. They are absolutely essential to a variety of scientific operations. Many factors go into defining the capabilities of these wires and cables and once defined, the resulting characteristics affect many other components of a research vessel, such as winch size and power, A-frame structure and strength, deck and internal space utilization, and the structural components of the vessel itself. Most importantly the vessel's capacity to accommodate the developing needs of science is determined by the availability of appropriate wires /cables and their matched handling components. The cost of a spool of wire or cable can exceed $250,000 and the cost of developing new wires and adapting (or building new) winches to handle those wires are not insignificant.
For these reasons it is absolutely imperative that the development of new “standard” wires and cables to be used in the UNOLS fleet be accomplished based on well-defined scientific requirements resulting from broad community input. The community also needs to examine ways to use new technology and engineering advancements to better utilize existing wires and cables whenever possible. The Standard UNOLS cables that we have all used over the past twenty plus years have served the community well and any changes to that suite of wires and cables should be designed to further improve the overall capabilities of the Academic Research Fleet. These changes cannot be made lightly.

What do we want to accomplish?

The purpose of these functional requirements is to define the capabilities and characteristics to be used in designing or evaluating designs for a possible new UNOLS standard smaller diameter electro-mechanical (EM) or electro-optical-mechanical (EOM) cable. This new cable should meet the needs of the oceanographic community for the next two or three decades and provide improved performance relative to the existing UNOLS standard small diameter EM cable (0.322 CTD cable). This cable would not replace the capability of the 0.680 coax or 0.681 EOM cable, which support the requirements for larger packages. These functional requirements will provide direction and goals to be used by cable designers and manufacturers in developing a cable design to meet the science community needs. The desired improvements relative to the existing “CTD cable” include increased payload and/or safety margin for deep casts using WOCE size CTD packages; a desire for higher bi-directional data telemetry and the continued need for comparable power transmission to instrument packages. Additionally other instrument packages have been introduced into the fleet and are currently being developed that involved continuously towing, either at fixed depths or in an undulating depth mode. Ideally, one new cable would meet all of these requirements, however it may be necessary to consider more than one design in order to achieve the desired results.

What should be done next, using this report?

The functional requirements contained in this report should become the starting point for a focused design, testing and acceptance process for designating a new UNOLS standard oceanographic cable. This can probably be accomplished in several ways, but in all cases it will be necessary for a focused and properly funded effort that verifies the community requirements, sets specifications to be met and provides for a testing program that verifies the suitability of any proposed cable. This report and the incorporated functional requirements should be used in any call for proposals or for evaluating any unsolicited proposals to develop a new cable. Additionally, this report can be used as a starting point for developing functional requirements for other existing or new wires or cables.

Goals, Objectives and Considerations for developing a new cable

Recommendations for future steps