Page 13 - Ranger Demo

was returned safely to the UK by the Irish Marine Institute vessel Celtic Voyager. Abandoned fishing nets are another hazard for gliders, particularly as many areas are of shared interest to scientific research and the fishing industry.
Operating any vehicle autonomously for such long periods, often in remote parts of the ocean far from any support vessels, means that mechanical failures can be critical. Glider operations which ten years ago would have been considered ground-breaking are now routine. As users become more experienced and manufacturers improve reliability, the focus has shifted to new sensors, improved autonomy and vehicles which can travel further, deeper and for longer. All these advances mean that glider operations are still risky, so a critical feature of all gliders is that they can send data back to the pilots during a mission. Even if a glider doesn’t make it home, the incredibly valuable data it has collected will suffice.
Figure 10 Royal Navy Glider used during the HECLA programme (Trial 1). The Glider wing was damaged and snapped off during the trial. Although the glider continued operations for several weeks an emergency recovery by the passing Irish Marine Institute vessel Celt
Summary
For both the academic and military, there is an increasing need to obtain more data to support an improved understanding of ocean complexity. For the academic community, high quality and quantity of data are required to enable the physics of the ocean to be understood, leading to improved ocean model forecast capability. The military oceanographer has similar requirements to the academics. However, the military has the added burden of needing near real-time data and almost immediate tactical interpretation to support command decisions. A particular case in point is the ability to understand the intricacies of the propagation of sound within a highly complex and dynamic ocean to maintain effective sonar capability. Gliders offer an excellent and low-cost capability to measure the
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