Survey Gangnam Style

Well it has been over 4 years since I have made a post on this blog and thought it fitting to return with a return trip to South Korea. A lot has happened in the last 4 years and I have been trying to resolve what Bathymetric Blundering is. In this time I have remained self employed with my consultancy, Bythymetry Consulting, as well as being employed for a year by SEA (Systems Engineering and Assessment Ltd) before being made redundant in April 2010. Since then I have continued earning a living doing support and training with the SWATHplus sonar. More recently I have been branching out as a Hydrographic surveyor as well as an operator and processor for other sonar systems, namely Geoacoustics Geoswath. My understanding of sonar and surveying has grown and this has been bolstered by a PgDip in Hydrography from the University of Plymouth on my way to an MSc and FIG/IHO Cat A certification. So with a wealth of experience and now qualifications to back up 16 years of working with interferometric sonars and 19 years working in offshore and near shore surveys is there any chance of continuing Bathymetric Blundering? Well yes there is, because, as I have often found, you are a victim of circumstance and however hard you try and influence things it is how you deal with events that can make or break a project or you as a surveyor/engineer.

I have recently been in Korea to ostensibly supply training on a new SWATHplus sonar to an organisation that run large grey vessels. On arrival though I find myself drawn into a full dry dock installation of the sonar system involving cutting and re-terminating transducer cables to allow them to penetrate the hull. Also involved in defining and wiring up the interface boxes in the sonar room and survey room.  Both of these are good lessons in being a jack of all trades, definitely useful having survey/sonar engineer skills not just hydrography/navigator skills as installations are certainly one of the most challenging and often enjoyable of times, even if you are working 14-16 hour days to try and get things working.
The major survey tasks though was to measure sensor offsets on a large vessel with the attitude sensor installed in the bowels of the vessel, the transducers hull mounted and the positioning/orientation sensors in the order of 20m higher and 10m forward of both. To measure these offsets I was given the ships sounding rope marked out in fathoms and a steel tape with 30cm missing. To top this I was not allowed to take any photographs of the process or sensor positions as in a sensitive site. So instead of a survey using a Total station to range and survey in the sensors to an accuracy or millimetres, I get questionable rope and measuring tape to get an accuracy hopefully to a 6th of a fathom.
So how can this get better? Well by requiring IHO Order1 accuracy when providing just high and low tide times for height control and a vessel that is difficult to maneuver to run the close and tight lines required for calibration in an area with wicked cross currents. To top this surveys lines up to 100m depth while having only enough rope for a 50m SOS dip and a light weight SVP that streams off in the current and gets only 30m depth. All this while trying to train an operator with very little English and no knowledge of hydrography to obtain IHO standard data for provision to the hydrographic office for assessment. Survey Gangnam Style!