* Posts by JamCam

3 posts • joined 22 Apr 2010

Godmother of Unix admins Evi Nemeth presumed lost at sea

JamCam

With respect to stability, or more properly, recovery from capsize. Nina has one of the best hull-forms for this, her angle of vanishing stability (AVS) should be 180 degrees or very close to it, so she'd come up straight away. In contrast most modern boats have considerably lower AVSs often between 115 1nd 130 degrees, as was discovered in the 1979 Fastnet and the1998 Sydney to Hobart, with some boats staying inverted for a long time. Incidentally, the Winston Churchill's loss in the 1998 Sydney Hobart race is closer to the kind of indecent that you'd expect with a boat such as Nina ( a heavy broach followed by very quick flooding).

Nina's lines are here:

http://www.wavetrain.net/news-a-views/485-schooner-nina-missing-and-presumed-sunk

Olin Stevens refers to her as having 'a tall staysail schooner rig and a rather light hull carrying a heavy lead keel' (Desirable and Undesirable Characteristics of Offshore Yachts. Ed. Rousmaniere. pp 26)

For stability curves of various hulls Rousmaiere pp72. Nina is similar to the first one.

On storm canvas. Don Street said he'd sailed Iolaire, a 1903 yawl, into 50kts and hove to in 70kts. The traditional storm survival tactic for long keelers is to heave to until the waves are breaking close to the boat, then run off. To that end you'd expect to keep the storm sails up through the blow, and may well, as Bill Tillman did leave them to blow out on the grounds that it's preferable to risking the crew's lives in getting them down.

As for deck houses yup, Adlard Coles in the first edition of Heavy Weather Sailing has many tales of smashed deck housed and tenders swept away (the tenders seem not to have smashed the deck, merely disappeared in the night)

If you're into this stuff both books well worth reading.

JamCam

THANKS STORM SAILS SHREDDED LAST NIGHT, NOW BARE POLES. GOINING 4KT 310DEG WILL UPDATE COURSE INFO @ 6PM

She was apparently well maintained, so it must have been some blow to shred the storm canvas.

Running under bare poles there is a risk of broaching, old wooden boats sometimes open up the seams between planks in a heavy broach, when this happens they can sink in seconds. Though I suspect we'll never know.

All very sad.

Nokia: digital SLRs are doomed

JamCam

Ergonomics and weight

Aside from the glory of good lenses and large sensors (the D700 continues to impress in the worst light), he ignores ergonomics, it's a lot easier to use a DSLR effectively than either a compact or a camera phone. The better DSLRs have had a lot of thought put into them as photographer's tools and once you've got past the intimidating controls become very easy to use.

Also weight, which confers inertia and means professionals, particularly documentary and press photographers can handhold to an eighth of a second or less, on shorter lenses, irrespective of image stabilisation. Slower than this and subject movement becomes a big issue.

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