1 Title of the Invention
Stability Augmentation System for Roll Rate Stabilization of.an Aircraft.
2 Field ofthe Invention
The invention relates specifically to a flight control system of the
5 Engineering field and particularly .to a stability augmentation system along
the rolling axis of a deep penetrating attack aircraft to provide stability,
control & handling characteristics especially during weapon deliveries at
low altitude flying. ·
3 Background of the Invention
1 0 Stability and control characteristics of an aircraft is assessed in the context
of flying and handling qualities requirements. For deep penetrating attack
aircrafts, the stability, control · & handling characteristics becomes
paramount during weapon deliveries at low altitude and high speed flying,
which results in sudden change of aircraft mass and in turn shift in the
15 centre of gravity of the aircraft which may leads to instability and in turn
cause· of an accident. Therefore for safe execution of the mission, it is
crucial to deploy a system in the aircraft which can support or augment the
efforts of the pilot in the want of desired stability.
3.1 Prior Art
. 20 Patent (US Patent number 4,198,017."1980-04-15):
It cited the control augmentation system for stabilizati,on and control of
flight vehicles, . in general for a hingeless rotor control problems and
specifically for AH56A Cheyenne Helicopter. It describe the control of
vehicle angular velocities in proportion to control input and in turn
25 stabilization of the corresponding vehicle attitude is augmented through
feedback path. It cited two types of augmentations, stability augmentation
and control augmentation both, ·to support trim and ground handling
features. Its stability augmentation comprises two feedback paths from
rate gyroscope with "fixed gains" to provide "rate plus attitude"
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Applicant: Hindustan Aeronautics Limited
stabilization. Its control augmentation comprises two feed