Spi or MPS Sock

1. The spi- or MPS-sock is particularly useful for shorthanded crews.
Using a sock and a good autopilot, it is even relatively easy to set and lower and MPS singlehanded.

2. Using bowlines, attach the downhaul guy to
the tack and the sheet to the clew.

The sock pull-line should be
tied down to a clamp on
deck so that the sock
cannot open on its
own whilst raising
the sock with the
halyard. Fig.2.

3. The spi halyard is attached to the stainless steel ring at the top of the sock. The sock should be hoisted in lee of a flying genoa or, as shown in Fig. 1, with the genoa already furled.
Fig.3 shows the inside layout of the upper part of the sock.