The Technician's Opinion
vertical bow of the F235 is certainly the most original part of
the very pleasing hull. A well-immersed sternfoot gives the F235
a fake mini-Transat look. The beam is situated far aft and has
been limited to 2m50 to allow for road transport. Less wide and
with a smaller sail surface, the F235 is of course not as powerful
as the Transat racing boats. The forward sections are quite full,
compensating the absence of a peak. The aft sections have a very
flat bottom and the bilge curves inwards above of the waterline.
The freeboard height is quite modest, especially aft and despite
the aft cabin layout. The flat bottom has a clear influence on
stability: as soon as the bilge is totally immersed stability
increases dramatically. One will rapidly heel to 10º or even
20º, but a wind speed of 19 knots is needed to heel to 30º.
With large sails, a genoa that is larger
than the mainsail, a very long waterline and a relatively small
wet surface, the F235 performs well, especially in light winds.
All our tests and computations were done with the fixed keel version.
A retractable keel and rudder can reduce the draught to 70cm if
The polar diagrams show that the best
VMG will be obtained sailing close to 45º. Performance for
10 and 20 knots are roughly equal as demonstrated by the VMG diagram.
The best VMG (at 3.55 knots) is achieved at 17 knots with a heel
close to 30º and two reefs (sail reefed by 25%). Close hauled
sailing and tacking will be quite difficult with winds over 20
knots, and the VMG decreases steadily to 2 knots at around 40
knots of wind. The polar diagrams also show us that one might
just as well sail straight abeam when going downwind, especially
in light winds. For instance, the best VMG by 5 knots wind is
at a 155º route.
The top diagram shows the VMG for various
wind speeds. It shows that at winds of 18 knots, it is recommended
to reef the mainsail 25%. When the wind hits 26 knots, reef the
main 40%. The First 235 will heel to 30 degrees by 20 knots wind.