Dyneema Lifelines

This morning's issue of Scuttlebutt, a daily electronic sailing newsletter, has a brief article on the new Racing Rules of Sailing due out in January 2013.  Particularly notable to me is the news that ISAF has approved HMPE (brand names Dyneema and Spectra) single-braid line for use as a replacement for 1 x 19 stainless steel wire.  You can read all about it in Section 3.14.6 on page 24 of ISAF's 2012-2013 Offshore Special Regulations.

US Sailing published an article in January 2010 on the use of single-braid HMPE line that you can read here. 

There are significant advantages to using HMPE single-braid line over steel wire:  15 times stronger than steel on a weight-for-weight basis, 8 times lighter than the equivalent diameter in steel wire, specific gravity of .98 - it floats, chemically inert - it won't corrode, and doesn't kink - no permanent bends.  HMPE single-braid also does not absorb water and is highly UV and chafe resistant.

As a replacement for 1 x 19 steel wire lifelines, HMPE represents a considerable weight savings and improvement in durabiity as well as a potential monetary savings.  Although the line is somewhat more expensive than steel wire, it is easily spliced and doesn't require expensive swaged end fittings.  HMPE single-braid is an enticing alternative to steel wire lifelines.