Getting Under the Bridge

A 324
By the very nature of long-distance voyaging, the charts and pilot books that are carried are often not the latest editions by the time a yacht reaches its destination. Unlike their coastal-sailing counterparts, bluewater voyagers are rarely in a position to receive updates and Notices to Mariners. So they know that they need to exercise special caution, plus they generally sail with a higher technical specification with regards to navigation equipment than those that sail local waters: radar, GPS (at least one and, more often than not, one or two spares), and electronic charts, but it’s also common for a sextant and appropriate sight-reduction publications to be carried.

Bluewater voyagers also learn to value appropriate local knowledge. In remote parts of the world, buoys are not always where the chart says they are, and if anyone knows where the channel is, it will be the local fishing fleet /supply boat/ferry.

For example, while in Indonesia, we safely navigated the entrance to the Kumai River in Borneo by following a local freighter. After a stay in the town of Kumai, 20 miles upriver, we departed by retracing our route. We had been at sea for a few hours, and the worst lightning storm we have experienced in 25 years of sailing exploded over our heads. Shards of lightning burst through the clouds and pierced the water around us, as though searching for their target. A strike seemed inevitable. Our spare GPS, hand-held VHF, portable echo sounder, and a supply of batteries were stuffed into the microwave, in the hope that it would act as a Faraday cage and protect the gear should we be struck. Out came the sextant in readiness for use if the lightning zapped us.

Though boats are hit in this area every year, we avoided damage and the next day anchored peacefully in the Lingga Islands, south of Singapore, to recover our composure. The sextant, not yet restowed, was nevertheless called upon. Cruising up through the Lingga Islands, we passed a headland and began our turn to port to pass between two islands. Before us the broad grin of a new suspension bridge spanned the channel between the islands, a detour would be a two-day sail.
 

The pilot book referred to “future plans to bridge the islands,” and the charts were mute on the subject. We weren’t sure that our masts would make it under the bridge safely. Some basic trigonometry resolved the issue, involving a distance off from the radar and a sextant angle on the bridge. We calculated we had 10 feet to spare. No role for the microwave this time.

By the time we arrived in the modern Harbor of Singapore, we thought we had met all of the navigational challenges that would confront us for a while. Singapore’s shipping lanes and harbor anchorages are notoriously busy, but a conscientious 360° visual watch and the prudent use of radar should suffice. And it did, but not without some surprises.

Our destination was Raffles Marina at the western end of Singapore, and we plotted a course through the port, taking into account the myriad channels and anchorages in the Harbor. Once again, the radar picture did not match the charts, but unlike in Borneo, where it was simply a positioning error in the charts, this time the land was a different shape from that depicted on the chart. A much more disturbing problem.

A spit of land lay ahead, straight across our route. It was the first example we saw of Singapore’s land-reclamation work. “New” land is being created at an astonishing rate, certainly faster than reflected in our charts, now a couple of years old. The reclamation is not in shallow coastal water; depths up to the edge of the spit were 90 feet or more. We had to make a detour of three miles to go around the first spit and then again around a second. A route that we had calculated to be 36 miles was actually 44 miles by the time we arrived at the marina. On this occasion, radar was the hero of the day.

Thankfully, the marina office had all the current updates for Singapore Harbor, so at least when we left we were better equipped than when we had arrived. However, we knew that the pilot books and charts that we bought in Singapore to cover our next year’s cruising up to the Mediterranean were getting out of date even as we carried them back to the boat. That they comprise only one component in our suite of navigational aids, and that the whole is greater than the sum of the parts, is reassuring to remember when operating in less than ideal environments.

 

Colleen Ryan and Brian Savage have voyaged aboard Theta Volantis, a Sundeer 64, since 1994. They are currently in the Mediterranean.

For example, while in Indonesia, we safely navigated the entrance to the Kumai River in Borneo by following a local freighter. After a stay in the town of Kumai, 20 miles upriver, we departed by retracing our route. We had been at sea for a few hours, and the worst lightning storm we have experienced in 25 years of sailing exploded over our heads. Shards of lightning burst through the clouds and pierced the water around us, as though searching for their target. A strike seemed inevitable. Our spare GPS, hand-held VHF, portable echo sounder, and a supply of batteries were stuffed into the microwave, in the hope that it would act as a Faraday cage and protect the gear should we be struck. Out came the sextant in readiness for use if the lightning zapped us.

Though boats are hit in this area every year, we avoided damage and the next day anchored peacefully in the Lingga Islands, south of Singapore, to recover our composure. The sextant, not yet restowed, was nevertheless called upon. Cruising up through the Lingga Islands, we passed a headland and began our turn to port to pass between two islands. Before us the broad grin of a new suspension bridge spanned the channel between the islands, a detour would be a two-day sail.

Image Credit: Brian Savage / Colleen Ryan
The suspension bridge in Indonesia's Lingga Islands.

The pilot book referred to "future plans to bridge the islands," and the charts were mute on the subject. We weren't sure that our masts would make it under the bridge safely. Some basic trigonometry resolved the issue, involving a distance off from the radar and a sextant angle on the bridge. We calculated we had 10 feet to spare. No role for the microwave this time.

By the time we arrived in the modern Harbor of Singapore, we thought we had met all of the navigational challenges that would confront us for a while. Singapore's shipping lanes and harbor anchorages are notoriously busy, but a conscientious 360� visual watch and the prudent use of radar should suffice. And it did, but not without some surprises.

Our destination was Raffles Marina at the western end of Singapore, and we plotted a course through the port, taking into account the myriad channels and anchorages in the Harbor. Once again, the radar picture did not match the charts, but unlike in Borneo, where it was simply a positioning error in the charts, this time the land was a different shape from that depicted on the chart. A much more disturbing problem.

A spit of land lay ahead, straight across our route. It was the first example we saw of Singapore's land-reclamation work. "New" land is being created at an astonishing rate, certainly faster than reflected in our charts, now a couple of years old. The reclamation is not in shallow coastal water; depths up to the edge of the spit were 90 feet or more. We had to make a detour of three miles to go around the first spit and then again around a second. A route that we had calculated to be 36 miles was actually 44 miles by the time we arrived at the marina. On this occasion, radar was the hero of the day.

Thankfully, the marina office had all the current updates for Singapore Harbor, so at least when we left we were better equipped than when we had arrived. However, we knew that the pilot books and charts that we bought in Singapore to cover our next year's cruising up to the Mediterranean were getting out of date even as we carried them back to the boat. That they comprise only one component in our suite of navigational aids, and that the whole is greater than the sum of the parts, is reassuring to remember when operating in less than ideal environments.

Colleen Ryan and Brian Savage have voyaged aboard Theta Volantis, a Sundeer 64, since 1994. They are currently in the Mediterranean.

By Ocean Navigator