STEALT

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TECHNOLO

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CONTENTS:1.What is stealth technology?2.RADAR and its working principle3.How to make things invisible?4.Drawbacks(limitations) of stealth5.Advantages of stealth6.Future scope7.Conclusion8.References

STEALTH

TECHNOLOGY1. Stealth is a technique in which we

can make any object almost invisible.

2.Stealth is an important technology which is used in military operations.

3.Stealth technology also known as LO technology (low observable technology).

4.This was developed mainly to evade the RADAR detection

5.The first stealth aircraft was developed in Germany during last years of WWII

The F-117A Nighthawk Stealth Fighter, a single seat, twin engine aircraft developed by Lockheed Martin, was the first aircraft designed to exploit low-observable stealth technology. 

RADAR

RADAR is the acronym for RAdio Detection and

Ranging.

Radar is an object-detection system that uses radio waves to determine the range, altitude, direction, or speed of objects

1. Radar is something that is in use all around us, although it (radio waves) is normally invisible.

2. Air traffic control uses radar to track planes both on the ground and in the air, and also to guide planes for smooth landings.

3.NASA uses radar to map the Earth and other planets, to track satellites and space debris and to help with things like docking and maneuvering.

4.The military uses it to detect the enemy and to guide weapons.

When people use radar, they are usually trying to accomplish one or all of the following three things:

1.Detect the presence of an object situated at some distance

2.Detect the speed of an object3.To map or locate something

All three of these objectives can be accomplished using:

1.ECHO2.DOPPLER SHIFT

ECHO• Echo is something you experience all

the time. If you shout into a well or a canyon, the echo comes back a moment later.

• The echo occurs because some of the sound waves in your shout reflect off of a surface (either the water or canyon wall) and travel back to your ears.

• The length of time between the moment you shout and the moment that you hear the echo is determined by the distance between you and the surface that creates the echo.

DOPPLER SHIFT

• Doppler shift occurs when sound is generated by, or reflected off of, a moving object.

• Let's say there is a car coming toward you at 60 miles per hour (mph) and its horn is blaring.

• You will hear the horn playing one "note" as the car approaches, but when the car passes you the sound of the horn will suddenly shift to a lower note.

• It's the same horn making the same sound the whole time. The change you hear is caused by Doppler shift.

• You can combine echo and Doppler shift in the following way. Say you send out a loud sound toward a car moving toward you.

• Some of the sound waves will bounce off the car (an echo).

• Because the car is moving toward you, however, the sound waves will be compressed.

• Therefore, the sound of the echo will have a higher pitch than the original sound you sent.

If you measure the pitch of the echo, you

can determine “how fast” the car is going.

HOW RADAR WORKS??• The radar dish or

antenna transmits pulses of radio waves or microwaves that bounce off any object in their path.

• The object returns a tiny part of the wave's energy to a dish or antenna that is usually located at the same site as the tranmitter.

Left: Antennas at Goldstone Deep Space Communications Complex (part of NASA's Deep Space Network) help provide radio communications for NASA's interplanetary spacecraft. Right: Surface search radar and air search radar are mounted on the foremast of a guided missile destroyer.

Photo courtesy NASA (left), Department of Defense (right)

HOW TO MAKE THINGS INVISIBLE ?The goal of stealth technology is to make an airplane

invisible to radar. There are two different ways to create invisibility:

1.The airplane can be shaped so that any radar signals it reflects are reflected away from the radar equipment.

2.The airplane can be covered in materials that absorb radar signals( also called as radar absorbing materials).

Apart from these things, the manufacturer should also consider the following……….

PRINCIPLE OF STEALTH TECHNOLOGY

1.Infrared detection.2.Visual detection.3.Acoustic detection.4.Radar detection.

Reduction in these detection is the principle of stealth

technology.

Most conventional aircraft have a rounded shape. This shape makes them aerodynamic, but it also creates a very efficient radar reflector. The round shape means that no matter where the radar signal hits the plane, some of the signal gets reflected back.

A stealth aircraft, on the other hand, is made up of completely flat surfaces and very sharp edges. When a radar signal hits a stealth plane, the signal reflects away at an angle, like this:

RADAR ABSORBING MATERIAL (RAM)

RAM is a class of materials used in stealth technology to disguise vehicle or structure from radar detection.

TYPES OF RAM1.Iron ball paint2.Foam absorber3.Jauman absorber

1. The material that is used to paint the stealth can be made of special materials like carbon powder in the glue or silicon based inorganic compound that would absorb the radar waves that fall on the plane.2. Dielectric materials are used as they are transparent to radar waves.3.Composites of ferrites are used to optimize dielectric and magnetic properties,

REDUCING INFRARED SIGNATURE

1. Infrared radiation are emitted by all matter above absolute zero temperature.

2.Hot materials, such as engine exhaust gasses or wing surfaces heated by friction with the air, emit more infrared radiations than cooler material.

3. Embedding jet engines inside the wings is one basic design step towards infrared stealth.

4. Other measures include extra shielding of hotter parts, mixing of cooler air with hot exhausts before emission etc.,

REDUCING ACOUSTIC SIGNATURE

1.The engines of the stealth planes should be designed such that the noise emitted by them is minimum.

2.Engines should be placed deep inside the plane.

3.Slow turning propellers were used to minimize the noise in earlier designs to avoid detection by enemy troops.

4.Incorporating acoustic-stealth measures, including sound-absorbent linings inside its engine intake and exhaust cowlings.

LIMITATIONS OF STEALTH

1.Instability of design2.Aerodynamic limitations3.Reduced payload4.Cost of maintenance5.Sensitive skin6.Cost of operations

ADVANTAGES OF STEALTH

1. Reduce the casualty rate during the war.

2. Develop the military secretes.

3. Bluff the anti-detective device .

4.Lesser number of stealth aircrafts required.

5. We can perform spy mission.

6. Can be used in Civil aviation.

STEALTH HELICOPTERNewest addition in stealth technology.

Designs for blades have emerged that can significantly reduce noise.

Used for raid on the compound of Osama bin Laden on May 2, 2011.

NORTHROP GRUMMAN B-2 SPIRITc Strategic stealth

bomber

National origin

U.S.A

manufacturer

Northrop Grumman corporation

First flight

17 July 1989

Introduction

April 1997

Status In service

Primary user

United states air force

produced

1988-2000

Number built

21

Unit cost

$737 million

B 2 SPIRIT

1.Max speed= Mach 0.95

2.Range = 11,100 km

3.Service ceiling= 15,200 km

4.Thrust/weight = 0.205

LOCKHEED MARTIN F 22 RAPTOR

Role Stealth air superiority fighter

National origin

U.S.A

Manufacturer

Lockheed Martin

First flight

7 sep 1997

Introduction

15 dec 2005

Status In service

Primary user

U.S air force

Produced 1996-2011

Number built

195

Unit cost $150 million

F 22 RAPTOR

F-35LIGHTNING IIRole Stealth multirole

fighter

National origin

U.S.A

Manufacturer

Lockheed Martin

First flight

15 DEC 2006

Introduction

Dec 2015

Status In initial production and testing, used for training by U.S

Primary users

U.S air force

Produced

2006- present

Number built

100 as of 2013

Unit cost $252.3 million

INDIA’S STEP TOWARDS STEALTH

HAL LIGHT COMBAT HELICOPTER (LCH)

HAL LIGHT COMBAT HELICOPTER

Role Attack helicopter

National origin

India

Manufacturer

Hindustan Aeronautics Limited

First flight

29 march 2010

Status Development trials

Primary users

Indian ArmyIndian Air Force

Produced

2010-present

Number built

3

Unit cost

$17.48 million

General characteristics

• Crew: 2 • Length: 15.8 m • Rotor diameter: 13.3 m • Height: 4.7 m • Disc area: 138.9 m² • Max. take off weight: 5,800 kg • Power plant : 2 × HAL/Turbo meca Shakti turbo shaft, 1,067 kw each

performanceHAL Light Combat Helicopter • Never exceed speed: 330 km/h (178 knots, 207 mph) • Maximum speed: 268 km/h (145 knots, 167 mph) • Range: 700 km (297 nmi, 342 mi) • Service ceiling: 6,500 m (21,300 ft)

SUKHOI T-50 STEALTH FIGHTER

FUTURE INDIAN STEALTH AIRCRAFTS

DRDO AURAAURA (Autonomous Unmanned Research Aircraft)

Role -Unmanned Stealth Bomber

Manufacturer- DRDO

Designer- DRDO

First flight- 2015

Introduction -2019-2020

Status -Under Development

Primary user- Indian Air Force

Indian Navy

Number built -0

Program cost -tbd

Unit cost -tbd

FUTURE INDIAN STEALTH AIRCRAFTS

HAL AMCA

HAL AMCA

Advanced Medium Combat Aircraft

Role -Stealth multirole fighter

National origin- India

Manufacturer- Hindustan Aeronautics Limited

Designer -Aeronautical Development Agency,

Defence Research and Development Organisation

First flight- Early 2020s

Introduction -TBD

Status- Under development

Primary users -Indian Air Force

Indian Navy

Unit cost -TBD

FUTURE SCOPE1.Hypersonics- the idea is to travel with M>5 to

avoid detection.

2. The infrared Invisibility Cloak: Shield one’s body heat from infrared sensors, effectively making them invisible to infrared cameras.

3. Plasma Stealth Technology: Also knows as Active Stealth Technology

Uses plasma to reduce the overall radar cross section of an aircraft.

4.TARANIS: A semi autonomous unmanned war plane designed to fly intercontinental missions. It will carry a variety of weapons enabling it to attack both aerial and ground targets.

5.To be incorporated not only in fighters and bombers but also in ships, helicopters, tanks and transport planes.

CONCLUSION• Undoubtedly, stealth technology is the

future of military combat and at present is one of the best technology to make things invisible as far as possible.

• But , the main problem with stealth is its very high cost and because of this, not all nations can adopt this technology.

• So we need to find ways to reduce cost or adopt a different technology with stealth like characteristics and at low cost (nano technology).

REFERENCES

1.www.google.com/images

2.en.Wikipedia.org

3.Book on Stealth technology-the art of black magic by J.JONES

4.Book on Stealth aircraft by BILL SWEETMAN

5.www.faqs.org

6.www.howstuffworks.com

7.www.youtube.com/

8.Google search engine

THANK YOU

QUERIES IF ANY ??