Acoustic Beacons Aid Scientific Exploration and Research

Two young engineers will soon be attempting a 250 kilometer crossing of the English channel in a pedal powered submarine. The two friends, Antoine Delafargue and Michael de Lagarde, are passionate about technical challenges, exploration, and sustainable management of natural resources. Their plan is to travel from Plymouth, England to Saint-Malo, France just a few meters above the sea floor in their human powered sub equipped with variety of observation instruments. The two pilots will provide propulsion through pedals attached to a crankshaft which is connected to a drive train that turns the sub’s propeller. The sealed hull is constructed of wood, fiberglass and a resin composite and has many of the features found on full a size submarine including ballast tanks, CO2 scrubbers, bow thrusters, and a sonar. The sub also has a number of safety features such as an emergency buoy and an acoustic pinger. The pinger will allow a surface vessel to track the sub throughout it’s journey.

   

The pair had hoped to make the crossing in the summer of 2016, but equipment problems caused them to postpone the trip. Antoine reported, "We had a few good dives down to 50 meters and the sub worked very well, but we had an issue with a gas sensor in the cabin. Traces of hydrogen were escaping from the sub’s batteries and were messing up our carbon monoxide sensor. We were able to test the pinger and found it worked well, getting ranges of up to 3 nautical miles. The 16 kHz transmission was clearly noticeable inside the sub, but not annoying." The pinger the team chose for their mission is JW Fishers SLFP-1. The advantage of this low frequency pinger is that it’s acoustic signal can be detected at a range of several miles, an obvious benefit when tracking a moving target across such a wide expanse of ocean. 

 

Sea trials will resume next spring with the onset of better weather. The team will be running the sub down to depths of 250 meters and practicing extended underwater operations staying submerged for periods of up to 24 hours. If all goes well, Delafargue and Lagarde will launch the official crossing sometime next summer.  Once the expedition is complete, the two intend to create a 250 kilometer long photographic mosaic of the seabed between the two countries. They then plan to exhibit their submarine and underwater images at  aquariums and museums across France, Monaco and the United Kingdom.

   

Another group using the low frequency pinger is Leidos; a spin-off of Science Applications International Corp (SAIC). Leidos is the fourth largest contractor to the US Department of Defense, and also works with the National Security Agency (NSA), US Department of Homeland Security, and the US Intelligence Community. In 2016 Leidos merged with Lockheed Martin’s Information Systems and Global Solutions (IS&GS) business to form a company with almost 40,000 employees and nearly 12 billion in annual revenues. One of their missions is to provide maritime ISR solutions by applying ocean physics, advanced sensors, communications, unmanned platforms, and autonomous systems, including: unmanned underwater solutions for intelligence and defense. The company recently acquired a JW Fishers SLFP-1 acoustic pinger for an undisclosed research project.

   

A few of the many other organizations using Fishers pingers are Scripps Institution of Oceanography, Canada’s Naval Engineering and Test Establishment (NETE), Prince William Sound Science Center in Alaska, the US Navy’s Expeditionary Combat Command and their Surface Warfare Center, the Ministry of National Defense in Lebanon, Ocean Sciences and Information Services in Ireland and numerous universities around the world.

 

For more information on the human powered sub project go to www.pilotfishproject.com. For info on any of Fishers acoustic devices or other underwater search systems go to www.jwfishers.com.