19-06-2012, 03:46 PM
STUDY AND MODELLING OF NOSE WHEEL USING CATIA.
INTRODUCTION TO NOSE WHEEL.
The Nose wheel is the structure that supports an aircraft
on the ground and allows it to taxing, takeoff and land.
Nose wheel usually includes wheels equipped with shock absorbers
for solid ground, but some aircraft are equipped with skis
for snow or floats for water, and skids or pontoons.
The nose gear consists of a single shock strut with
one or two wheels attached
The mechanism also acts as a shimmy damper to prevent
oscillation.
CONVENTIONAL VS TRICYCLE.
It allows more forceful application of the brakes without
the danger of nosing the aircraft over.
It permits better visibility for the pilot during ground operations.
It prevents the tendency for the aircraft to ground loop.
The nose wheel equipped aircraft also is easier to handle on the
ground in high winds due to its wing negative angle of attack.
TYPES OF STEERING SYSTEMS.
ELECTRICALLY CONTROLLED
The nose gear is steered by an electrically controlled, hydraulic
powered steering cylinder which is mounted on the nose
gear recoil strut.
The cylinder is connected through mechanical linkage to
an eccentrically mounted drive stud.
MECHANICALLY CONTROLLED
Nose steering system is mechanically con-trolled and hydraulically
actuated in much the same manner as an electrically controlled
nose steering system.
It serves the same dual function of providing steering and
dampening, when steering is not engaged.
CONCLUSION.
The system boasts an efficiency of 40-50% as opposed to the 33-35%
achieved by the conventional coupled generator methodology.
It can cut down aircraft emissions by 27% on the whole.
It may well end up saving about 400 liters of fuel daily.
The fuel cell system responsible for delivering electrical energy
is capable of powering the nose wheel of an aircraft weighing
up to 70 tons , a workload limit of 120 tons.
The Electric Nose Wheel not only cuts down fuel consumption but it
brings down noise emission during taxi movements substantially.