Search planning

Search planning

We want to search for Triumph using a sidescan sonar, when we have narrowed her position down to a smaller area, and when the Greek authorities give us permission to do so.

We need to acquire a sidescan sonar, with a navigation and plotting computer, and a cable capable of getting the sonar down to several hundred feet of depth. All-in, the kit is likely to cost in the region of £40k, though if Triumph is lying in shallower water then that number might be halved. There are several possible suppliers of sonars - CMax in the UK, Imagenex, Shark, Teledyne, and a couple more. We will also need a deep-water camera mounted in a remotely operated vehicle to photograph the wreck. The most likely pick at the moment is the DeepTrekker, from Canada.

Naturally we need a boat to tow the sonar through the water. The boat has several requirements:

She needs to be capable of operating for sustained periods, day and night, in open sea, and potentially in bad weather, so she needs a deep hull and good stability.
She needs to be able to operate at slow speeds for long periods of time. In practice the ideal solution is a twin engine setup with a coarse pitch propellor, allowing a towing speed of 2-3 knots operating on one engine at slow revs.
With a search team of four or five people plsu an observer from the Greek authorities she needs to be able to sleep and feed at least three people.
The search equipment needs mains power, probably 110 volts, so she needs to have a separate generator.
With the large amount of towing cable required the search boat needs a clear aft deck on which to mount a cable winch, and from which equipment can be launched and recovered.
She needs to be fuel efficient, since the search will take some time.

These requirements mean that the ideal search boat is probably a trawler-style yacht of around 40 feet and 25 tonnes, with twin 120 hp diesels, an 8kw generator and two cabins. With this specification, and operating at 2-3 knots on a single engine, fuel burn will be around 1.5 litres per hour, or £30 per day. Boats like these can be acquired in the Mediterranean for a cost of around £40k.

The searchis likely to take several months. The search area is some 1,000 square kilometres. We can search 1 square kilometre in about six hours (faster as we get better at it), so the search might take the best part of a year once we factor in repairs, weather, transit time to and from the base port for crew changes and supplies, and the distractions of marine traffic. We know that others are also searching for Triumph, and would greatly welcome their success if they find her first.