Aeroacoustics - SCHUBERTH C3 Manual De Usuario

f. The helmeT
5. AERODYNAMICS
All SCHUBERTH motorcycle and racing helmets are developed and
optimised in SCHUBERTH's own wind tunnel under scientific, precisely
defined conditions.
The C3 is specifically designed for a touring or sport touring riding
®
posture and remains stable in the air current. Even when travelling at
high speeds, the C3 generates practically no upward lift. Other
®
characteristics of the C3 are improved air resistance and excellent
®
directional stability. In addition, the buffeting often experienced at
high speed on an unfaired motorcycle is significantly reduced.
Note:
Please note that the strong eddy currents that can occur at
the edges of the wind shadow with faired motorcycles due to
the fairing can have a considerable effect on the aerodynamic
characteristics of a helmet.
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6. AEROACOUSTICS

We have paid a lot of attention improving the acoustic properties of
the C3 without a reduction of comfort. Various features developed
®
in SCHUBERTH's wind tunnel (such as special adaptation of the wind
deflector in the chin area and the shape of the acoustic collar) as
well as the choice of special materials eliminates drafts and makes
the helmet quieter*. This enables relaxed riding – especially on long
journeys – and enhances concentration.
A quiet helmet is characterized by low wind noise. Wind noise arises
through turbulent swirling of the air that flows around the helmet. The
turbulence generates local pressure fluctuations, which are detected
inside the helmet as noise (so-called pseudo noise). Only the wearer
of the helmet hears this noise. With most motorcycles and helmets,
engine noise is covered up by this wind noise from around 100 kph
upwards.
* Acoustic values can vary depending on type of motorcycle, fairing design, riding
posture and body size.
Warning:
The actual road speed can be underestimated slightly as
a result of the acoustic optimisation of the helmet and the
accompanying low wind noise. i.e. don't rely on your sense of
hearing to judge road speed – check your speedometer.
Warning:
Wearing a helmet reduces your ability to hear external sounds.
For safe riding, be aware of how your perception of speed, road
conditions and (traffic) sounds is affected by your helmet.
Note:
Please note that with faired motorcycles strong eddy currents
occur at the edges of the wind shadow. This can considerably
reduce the aero-acoustic performance of the helmet. The fairing
of the motorcycle should be adapted so that turbulence does
not strike the bottom surface of the helmet.
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