Sparkling Spars

Janet Hartman of Beaufort, North Carolina, asks:"Recently I contacted the National Ocean Survey (NOS) to ask whether the authorized clearances for overhead cables shown on their charts include the extra distance needed to avoid arcing. I received an email from nautical.charting@noaa.gov stating 'The ‘authorized clearance’ for an overhead power cable does not include the
Author:
Updated:
Original:

Janet Hartman of Beaufort, North Carolina, asks:

"Recently I contacted the National Ocean Survey (NOS) to ask whether the authorized clearances for overhead cables shown on their charts include the extra distance needed to avoid arcing. I received an email from nautical.charting@noaa.gov stating 'The ‘authorized clearance’ for an overhead power cable does not include the clearance necessary to avoid possible arcing. The clearance indicates the distance between the water level and the cable.'

An electrician friend of mine tells me the distance needed to avoid arcing varies depending on a cable’s voltage. So how can you know how much clearance you need when sailing under a cable? Local politicians tell me that, according to OSHA, a mast must not come within 10 feet of an overhead cable. I wonder whether local bridge tenders might refuse to open up for a sailboat whose mast might come within 10 feet of a cable on the other side of the bridge? I also thought the OSHA restriction applied only to construction and electrical equipment, not to sailboats that are underway. Can you shed any more light on what seems to be a problem with no apparent answer?"

Nigel Calder replies:

Although I hadn’t thought about the problem before you raised it, there’s no question this could be a matter of life or death in certain situations. In practice, of course, most of us don’t push our mast clearances to the limit. As for your local bridge operators, I strongly suspect cables near bridges are insulated, which means they are not an issue.

But high-voltage cables on major pylons in this country can carry up to 750,000 volts and they definitely are not insulated. They are potentially lethal, and I for one will make sure I give them a generous clearance from now on.

Related

NewBoatsTwitter

New Boats: A Mix of Speed and Smarts

While it’s safe to say that U.S. production boatbuilding is a shadow of its former self, one North American company that is still going strong is Rhode Island-based J/Boats. Not only that, but far from just surviving, the company continues to push the envelope, ...read more

01-LEAD-170914_JR_WCSEnoshima19_327556_0704

Enoshima Japan Olympics

If experience has a tone, it would sound like three-time Olympian and 470 sailor Stu McNay—steady, measured, with a positive, almost Mr. Rogers feeling. “Each Game has a unique flavor,” he says, the day before last spring’s 470 European Championships, one of the rare events he ...read more

Amel50-2048x

Boat Review: Amel 50

It is possible to cross an ocean in almost anything that will float, just as you could cross the United States on anything with wheels. But to voyage safely, swiftly and comfortably calls for a good deal more than the minimum. That’s where bluewater specialist Amel comes into ...read more

01-LEAD-lagoon46-ncz4503-a3

10 Places to Cruise With a Catamaran

Navel gazing doesn’t get much better than from the deck of a sailboat anchored somewhere exotic. You can think great thoughts staring up at the stars from a South Seas anchorage. It’s also better doing so on a catamaran. Full confession: I’m a cat convert, a cat evangelist if ...read more

Radome

Ask SAIL: Some Random TLC

Q: I recently removed my radar’s white radome, which covers the internal rotating antenna. I gave the radome a light sandblasting to clear it of years of grime and discoloring. Should I paint it, too? — B. Anderson, Aberdeen, MD GORDON WEST REPLIES Stop! First, make sure the ...read more

L42-Sea-Trails-3728

Boat Review: Leopard 42

Sticking with its proven design formula, but also cherry-picking popular features from its recent models, Leopard Catamarans has launched a “best of” package with this new boat that sold nearly 30 units before hull #1 even touched water. Like a greatest hits album, the Leopard ...read more

01-LEAD-Cut8

Know how: Reinforcing Engine Stringers

If I were to ask, “What are the top five parts of the engine you want to be able to easily access?” How would you respond? Would it be the dipstick? The overflow coolant? I’d wager the raw water pump and its impeller would also make the list. Am I right? The reason we want to be ...read more

Sail-VOE-4-a

Experience: Under the Eyes of the Bar Bunch

Sitting quietly at the bar of a local yacht club, I gaze out over a rambunctious Lake Michigan on a sunny but blustery spring afternoon. I am enjoying watching a small sloop approaching the marina and recognize it as belonging to one of our newest members. “Pretty little thing. ...read more