...continued
Well in the cold light of day things didn't look so bad. Yes there was a
lot of carnage but it was surprisingly confined. When the rig came down
it chopped across the beam. Although the beam was fractured and split,
some of the internal bulkheads were still intact. This means it wouldn't
require a major rebuild. I struggled to work out how to repair the wing.
The shape is complex and we don't have the moulds with us. I cut away
all the mush and decided to try and work with what was left. Many of the
FIBREFUSION waterjet cut ribs were also beaten up. I would have to
remake them.
The fact is that we came down here very well prepared. We have
everything we need to carry out major repairs. The broken carbon strut
can be instantly replaced with the one off the Mk1 DOYLES soft rig. The
wishbone can be rebuilt, local friends offered to straighten out the
metal work and we CAN fix the wing and beam.

It is now one week later and the job is 75% finished. We will be back on
the water in a few days.

So what happened you may well ask?

From my point of view I started the run by running away from the beach
for about 40-50 meters and then turning into the wind to hook up the
apparent wind onto the wing. Once this was done SAILROCKET accelerated
very quickly in a straight line. The steering didn't feel right. I had
made two mistakes. 1/ I was barefoot and although it felt comfortable at
rest, when I really had to stand on the controls I didn't have the power
that shoes afford 2/ I hadn't adjusted the foot steering controls to
compensate for not having shoes. When Sailrocket began to turn into the
wind I couldn't steer against it. The rudder had been given more rake so
I could have more feel but it proved to be too much. I was being very
careful not to oversheet the wing and this lead to Sailrocket turning
into the wind. The line of thrust from the sail was angled well behind
the keel/foil. I had two options as the beach approached rapidly, sheet
on hard to bring the line of thrust forward and perhaps allow me to
regain steerage... Or bail out. The trouble with option one was that I
was already relatively close to the beach and sheeting on would quickly
put us over 40 knots. If I couldn't regain enough steerage then it would
all be over in a couple of seconds. I wasn't happy with the steering so
chose to bail out instead. I turned into the wind and eased the wingsail
out slightly. The rig came down instantly.

The sail doesn't just luff into the wind, flap and depower like a normal
rig. It actually spins so that the leading edge develops huge amounts of
negative thrust. Easing the sheet combined with turning into the wind
made the wing give a large compressive load on the strut which caused
the previously mentioned strut retention line to fail. The leading edge
of the wing continued to rotate downwards making the wing accelerate
into the water like a powered up kite crash. It was sickening. We spent
a year building this thing detail by detail.

The crash highlighted a few issues. Sure the strut retaining line wasn't
strong enough but no we think it may be a good fuse as the back winding
loads of the rig may have been strong enough to cause the beam itself to
break.

Malcolm has gone over all the performance data and believes that at the
speeds we were going that we were simply going through a transition
stage where the apparent wind has swung forward and is beginning to
build in earnest. Once we start going real quick the helm should become
neautral again. One thing is for sure and that is that I no longer want
this boat to ever head for the shore. We are designing a drogue so that
we can slow down in a straight line. The thought of heading into the
beach and easing out the wing at 50 knots of boat speed is just not to
be entertained.

So I am writing this today in the container as we have just go a 3G card
and our internet situation is improving. I am about to pull on a white
dust suit and clean up all the repairs with a grinder and sandpaper.
Frank has dropped off the straight-as-new metal work and the gig is
definitely back on.

This boat is tough as nails. This wing survived an absolute smash-up
situation.

Nice work Chris and the boys at AEROTROPE.

We'll be back soon.

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