Experimental research

Overall 10.5 m
Beam 7.3 m
Air Draft 3.2 m
Draft 0.4 m
Weight for tests 3.5 – 4.5 t
Engines 2 x 200 Hp Outboards

Research and development witha 10.5 m prototype

  • Speed up to 61 knots
  • Building started in september 2014 and launch in February2015 in La Rochelle

Testing campaign

  • Calm water performance
  • Effect of wind
  • Sea keeping
  • Manoeuvering

Instrumentation

• Anemometers, windvanes, GPS, …
• Engine parameters (propeller and flow speeds, consumption, …)
• Instrumented bracket between hull and outboard engine
• Inertial Measurement Unit

2015-2017

More than 4000 Nautical miles sailed
Up to 2 m waves and 30 knots winds

Not a single failure

Simulations validation withexperiments

Experimental measurements confirms the numerical predictions.
The accuracy of A2V design tools is confirmed.

Comparison with predicted values

Each point = time averaged results on 10, 20 or 40 second runs
selected on low standard deviation
TWSx : True wind speed projected on vessel’s longitudinal axis

Seakeeping measurements usinginertial unit

Seakeeping trial record :
– Speed 40 knots
– Seastate 4 (between 1.5 m and 1.75 m significant wave height)
– 25 minutes head waves
– 20 minutes stern waves

Seakeeping measurements usinginertial unit

Measured accelerations onboard A2V prototype :
Seastate : 4 (1.75 m Significant wave height)
Length of the run : 45 minutes
Speed : 40 knots
Results : Only 20 shocks above 1.3g. Maximum shock <2g

A2V 10.5m Prototype lessons after4000 Nautical miles

Provides a very comfortable ride at full speed up to seastate 2
Can operate at full speed in sea state 3
Can operate at high speed in seastates 3-4 depending on the
heading and sea conditions
Can sail in seastate 4-5 in safe mode, between 10 and 20 knots
Generates no waves in the wake

High speed manoeuvrability

GPS track with both engines at same RPM
and 15 degrees rudder angle
Speed from 16 to 36 knots
Turning radius : 75m at 35 knots