This document discusses the gyroscopic effect on airplanes. It begins by defining key terms related to gyroscopes like axis of spin, gyroscopic effect, precession, and axis of precession. It explains that when a spinning gyroscope experiences a torque perpendicular to its axis of spin, it will precess around an axis perpendicular to both. On airplanes, the spinning rotor of the vertical gyro acts to maintain equilibrium. For example, if the nose is pushed left, the rotor will cause the nose to rise and tail to dip due to the gyroscopic effect. The direction of precession depends on whether the rotor is spinning clockwise or counterclockwise. The document provides diagrams to illustrate these concepts.

1. Subject :- Theory of Machines II
T.E. Mechanical (302043)
Unit 5 GYROSCOPE
5.3 Gyoscopic Effect on Aeroplane
By
Prof. K. N. Wakchaure(Asst Professor)
Department of Mechanical Engineering
Sanjivani College of Engineering
(An Autonomous Institute)
Kopargaon, Maharashtra
Email: wakchaurekiranmech@Sanjivani.org.in Mobile:- +91-7588025393
Sanjivani Rural Education Society’s
Sanjivani College of Engineering, Kopargaon-423603
( An Autonomous Institute Affiliated to Savitribai Phule Pune University, Pune)
NAAC ‘A’ Grade Accredited, ISO 9001:2015 Certified

2. INTRODUCTION
• Gyroscope: It is a body which while spinning about an axis is free to move in other direction under the action of external
forces.
• Axis of spin: It is axis about which the body revolves.
• Gyroscopic effect: Consider a body spinning about an axis OX . If a couple represented by a vector OZ perpendicular to
OX is applied, then the body tries to precess about an axis OY, which is perpendicular to both OX and OZ. This combined
effect is called gyroscopic or precessional effect.
• The plane of spin, plane of precession, and plane of gyroscopic couple are mutually perpendicular.
• Precession: It means the rotation about the third axis OY, which is perpendicular to both the spin axis OX and the couple
axis OZ.
• Axis of precession: The third axis OY about which a body revolves and is perpendicular to both the spin axis OX and
couple axis OZ, is called the axis of precession.
• Mechanical gyroscope: It is a special mechanism generally employed for the control of angular motion of a body.
Gyroscope is an instrument, which appears as a device possessing intelligence. Gyroscopic effects can be used in several
applications for directional control, e.g. in Gyrocompass used on aeroplanes and ships and in inertia guidance control
system for missiles and space craft control.

3. Plane of Precession
Plane of
Spinning
Plane of Gyroscopic
couple
Axis of Spinning
AxisofPrecession
Plane of Precession
Plane of
Spinning
Plane of
Gyroscopic couple
INTRODUCTION

4. Anticlockwise
Nose EndTail End
Axis of Spinning
AxisofPrecession
Rotor Rotates in clockwise direction.
Left
Dip The Nose Raise the Tail
Axis of Gyroscopic coupleCondition
Nose End
CW
LEFT

5. Anticlockwise
Tail EndNose End
Axis of Spinning
AxisofPrecession
Rotor Rotates in clockwise direction.
Left
Raise The Nose Dip the Tail
Axis of Gyroscopic couple
Condition
TAIL End
CW
LEFT

6. Anticlockwise
Nose EndTail End
Axis of Spinning
Rotor Rotates in Anti clockwise direction.
Left
Raise The Nose Dip the Tail
Axis of Gyroscopic couple
AxisofPrecession
Condition
Nose End
CCW
LEFT

7. Anticlockwise
Tail EndNose End
Axis of Spinning
Rotor Rotates in Anti clockwise direction.
Left
Dip The Nose Raise the Tail
Axis of Gyroscopic couple
AxisofPrecession
Condition
TAIL End
CCW
LEFT

8. Dip The Nose Raise the Tail
Anticlockwise
Nose EndTail End
Axis of Spinning
AxisofPrecession
Rotor Rotates in clockwise direction.
Right
Axis of Gyroscopic couple
Condition
Nose End
CCW
RIGHT

9. Dip The Nose Raise the Tail
Anticlockwise
Tail EndNose End
Axis of Spinning
AxisofPrecession
Rotor Rotates in clockwise direction.
Right
Axis of Gyroscopic couple
Condition
Tail End
CW
RIGHT

10. Raise The Nose Raise the Tail
Anticlockwise
Tail EndNose End
Axis of Spinning
Rotor Rotates in Aniclockwise direction.
Right
Axis of Gyroscopic couple
Condition
Tail End
CCW
RIGHT
AxisofPrecession

11. Raise The Nose Dip the Tail
Anticlockwise
Tail EndNose End
Axis of Spinning
AxisofPrecession
Rotor Rotates in clockwise direction.
Right
Axis of Gyroscopic coupleCondition
Nose
CW
RIGHT

12. Thank You….
12Subject :- Theory of Machines II