Yachting World - July 2018

87

{}

If the G4 heels too far (around 45° depending on

set-up) a capsize safety mode powers down all

electronics, and a CO^2 /NO^2 gas canister auto-

inflates in the masthead to prevent it turning turtle.

There are also large red safety buttons in
the cockpit and saloon, which can be used to
manually activate the ‘dump’ function. However,
Mischa Heemskerk, the professional sailor and
foiling expert who works with DNA to test their
fleet of foiling boats, says the system response
speed is much faster than a person in most
situations – he described it as putting an ABS
braking system into a Ferrari.

Testing the limits
Over months of development and testing the
team has thoroughly explored the limits of the
‘auto dump’ system, from conservative modes
to sailing the boat much more aggressively
than any private owner would – Heemskerk is

an A Class world champion and

Olympic coach.

Before going out for the day,

a simple ‘double click’ set-up

adjusts the pre-programmed

settings for the day’s conditions,

including wind strength and all-up

weight, depending how many crew and guests

are aboard (the G4 weighs just 4.3 tonnes).

The G4 will foil once wind speeds get up to

around 17-18 knots (DNA suggest a maximum

wind strength of 30 knots). In ‘foiling cruise’

mode she’ll get up to 30 knots of boatspeed,

but in ‘sport’ or ‘race’ mode has the potential to

hit 39-40 knots.

Once underway the G4’s real party trick

is not only maintaining stable

flight in a straight line, but also

controlling the foils into and out

of a tack or gybe. Hit the ‘Tack’

button, slow down, then push the

tiller away and the G4 automated

system will lift and lower the boards

through the tack. This was, unsurprising, one of

the hardest bits of the software development

to get right. It can also be stopped mid-way

through the manoeuvre.

The power demands of the controls mean

that the new G4 has a bank of lithium batteries,

as well as a generator. It should be able to

sail for one or two days without needing the

generator. The systems have increased the

IN DOCK

The G4 has a

retractable electric

motor, and a dedicated

‘harbour’ mode for

mooring.

i

All photos by Jasper van Staveren/DNA