This document discusses stealth technology, which aims to make objects invisible to radar detection. It provides a brief history of stealth technology development during World War 2 by the Germans. It then explains how radar systems work using radio waves and echo detection. It describes different methods used in stealth technology to reduce radar cross-sections, including shaping aircrafts at acute angles, using radar-absorbing materials, and active cancellation techniques. The document outlines advantages like cost-effectiveness but also disadvantages such as reduced payload and high costs to develop stealth aircraft. In conclusion, it discusses how stealth technology is the future of military combat but is currently very expensive.

1. STEALTH TECHNOLOGY
Presented by:
ROHITH CHIMMANI
13311A04B3
ECE-C

2. Outline
 Introduction
 History
 Radar & Its Working
 Types of Detection
 Radar Cross Section (RCS)
 Advantages & Disadvantages
 Conclusion

3. Introduction
 What’s stealth technology?
• A technique of making objects invisible
• An important technology used in military operations
• Also known as LOT (Low Observable Technology)

4. • Task of Stealth Technology

5. HISTORY
 World War II played in important role in stealth technology development.
 Germans were the 1st
developers
 Germans developed the stealth Nano-Paint during the WW-II

6. What is a Radar system?
 Radar system is a system that help pilot in navigating while fly in space
 It uses a continuous wave and frequency to keep in touch with
 By radar system we could know how far the object is and its velocity

7. How it works?
 Radar system based on the techniques of
Echo and Doppler Shift using Radio waves.
 The echo of a sound can be used to
determine how far away something is.
 The Doppler shift of the echo can
determine how fast something is going.
 There are sender and receiver that have
been installed on ground and aircraft as
well

8. How Stealth Technology avoid Radar
detection ?
 Two Major factors
Aircraft design Materials been used

9. Types of Detection
 Different radar signatures of vehicles can be catergorized as following:
 Radar Cross Section (RCS)
 Infrared Signature
 Acoustic Signature
 Visible Signature

10. Radar Cross Section
 Radar mainly work on electromagnetic wave reflection.
 In order to avoid these reflection towards the radar receiver, we
have to reduce the radar cross section of object.
 Radar cross section
(RCS) defines the ability of a vehicle to reflect a radar signal.

11. RCS Reduction Technique
(Reduction in Radar Detection)
 Purpose shaping :
The shape of the target’s reflecting surfaces is designed such that they
reflect energy away from the source.
 Radar absorbent material :
As an addition to highly reflective surfaces.
 Active Cancellation :
Target generates a radar signal equal in intensity but opposite in phase to
the predicted reflection of an incident radar signal

12. Vehicle shape
 It should be coated with Radar Absorbing Materials
 Which deflect , absorbed incoming radar waves and reduce the detection
range.
Figure: Radar absorbing materials

13. Vehicle shape
 It should be coated with Radar Absorbing Materials
 Its tail should be kept Acute angle
 Planes wings has to kept at acute
 Design of the Nose

14. Shaping
 Normal design  Curved design

15. F117 A NIGHTHAWK

16. Active Cancellation
 In this method we have some RF source
on object (plane, ship) which modify
radar signal but in opposite phase that
generate destructive interference.
 Thus by the use of these three methods
we can reduce RCS of our plane and
can make them low observable.

17. Infra-red stealth
 Method to decrease the IR signature of the engines is to use
exhaust masking.
 Hot zones such as engine exhaust , wing surface [friction due to
air] get heated which rather increases the visibility
 This is accomplished by placing the engines on top of the body
and the wings, by which exhausts cannot be seen from below.
 These part should be kept cool as possible it can be ,
 Option would be mixing of cool air with the hot engine exhaust

18. Infra-red Stealth

19. Visual Stealth
 Low visibility is desirable for all military
applications
 Earlier stealth aircraft were painted black
and thus could be used during nights
 Now days an electro chromic polymer is
being developed for daytime stealth
 These polymer sheets sense nature of the
surrounding and change there color
accordingly

20. Visible Stealth
 Stealth Nano - Carbon Paint
 “Blackest “ known material of the world
 Absorb 99% of the received signal
 Excellent Electrical Conductivity and High Strength

21.  Plasma will cover the whole body of the aircraft
 Plasma cloud will observe the Radar waves and prevent aircraft detection
Plasma Stealth

22. Advantages
 Few number of stealth aircrafts = Huge number of conventional aircrafts
[Economical in long term]

23. Advantages
 Few number of stealth aircrafts = Huge number of conventional aircrafts
[Economical in long term]
 Keeping the enemy in fear of aircraft’s existence. So they will remain in
defence mood
 The natural competition of war will result in economically weakening of the
enemy.
 Diplomatic result: Stealth aircrafts have high military technology and
military secrets

24. Disadvantages
 Low speed and Maneuverability.
 Low amount of carried payload

25. Disadvantages
 Low speed and Maneuverability.
 Low amount of carried payload
 High cost:
 B-2 bomber: $2 billion
 F-117A: $70 million
 F-22: $100 million
 Wing shape => Unstable flight, Not enough uplift force for takeoff, Needing
of complex computerized system for stable flight.

26. Conclusion
 Stealth Technology is the future of military combat technology.
 In near future stealth technology can be used in other facilities like ships,
helicopters, vehicles, etc.
 The main problem of this technology is its high cost.
 Stealth technology due to its high cost, cannot be a proper choice for
developing countries.
 New developments in other fields of technology such as Nanotechnology
can be used instead of stealth technology due to their low cost.

27. References
http://en.wikipedia.org/wiki/Stealth_technology
http://en.wikipedia.org/wiki/Radar
http://en.wikipedia.org/wiki/Stealth_ship
http://science.howstuffworks.com/question69.htm
http://www.hyperstealth.com/Quantum-Stealth

28. THANK YOU