STEALTH TECHNOLOGY

Presented by:

Anuja Dhar & Anuradha JV-

I/11/4301 JV-I/11/4336

M.TECH(EC)-B.TECH(EC)

Stealth Technology ?

Origin

Stealth Technology In Aircrafts

Radar Detection

Working Principles

Measuring stealth

Applications

Disadvantages

Conclusion

“making things invisible”

Stealth means “secrecy”

hide or evade

detection

Low observable

• Evade detection

• Counter radar signature

• Infrared detection

Why ?

• Caveman• Soldiers• Submarines• Aircrafts

How ?• In late 1930’s• During ww-2• Undetectable

periscope by submarines

When ?• In 1960• Lokheed SR-71• In Germany

existence

Stealth Technology

In Aircrafts

Hiding

from radar

Low

observable

technology

Radar cross

section

Radar signature

Radar antenna transmits radio

waves

Encounter with enemy

Radio waves get reflected back

Measurement of the time for reflection

Calculation of the distance of the object

Metal body of an airplane is good at reflecting signals

A radar signature is how big the airplane on radar appears from a specific angle and distance.

Radar cross section-cross-sectional area of a perfectly reflecting sphere that would produce the same strength reflection as would the object

Integration of many techniques and materials

Uses the principles of reflection ,redirection and absorption:

RCS reductions

Visual

Infrared

Acoustic

Radar

Almost since the invention of radar, various

techniques have been tried to minimize

detection. Some of the techniques used for this

purpose are:

Vehicle shape and

design

RAM (radar

absorbing material)

Stealth vehicle : shapes and design

Coated with RAM

Must have RAS

Shaped for low RCS

Non-metallic

frame

Carbon powder in glue or silicon based inorganic compound

Material info is kept secret by the military forces

Reduces the radar cross section and makes object smaller

Dielectric –transparent to the radar waves

Nanostructural composites of magnetic ferrite and carbon fiber -to optimize dielectric & magnetic properties.

RASDeflects

incoming radar

Reduces detection

range

Structures include wings,

refueling boom

Uses reflection

Tail angle not=90 degree

Design of nose

it must bury the engines within the

wings

Conventional aircrafts Stealth aircrafts

Environment blending coloring .

Planes are painted black or like matte

paint .

Use of special coatings to minimize

bright reflections.

Appearance of insects or birds to

radar.

They use YEHUDI lights or gray color in

the day time.

Source of infrared radiations are:

1)Engine exhaust gases

2)wings surfaces heated by friction with air

Measures of infrared radiations:

1)Embedding jet engines inside wings.

2)Extra shielding of hot parts.

3)Mixing of cool air with hot exhaust before emission

• Aircrafts are quieted by silencer suppressor : high- by –pass-ratio turbofan engines .

• Fly high

• Fly past the speed of the sound

Active stealth

Inject steam of plasma

Covers entire body of aircraft

Absorb electromagnetic energy of radar

First developed by Russians-

“Soviet Russian Space Program”

The size of a target’s image on radar is measured by the RCS.

If we rotate flat plate ,the amount of energy reflected directly back to the transmitter is

reduced, so the RCS is reduced.

If the RCS was directly related to the target’s cross sectional area ,to reduce it, we have to make the

physical profile smaller.

In Marine Ships In

Aircrafts

Stealth Plane

Stealth technology is used in making passengers plane also.

Reduce amount of payload

Can’t make sharp curves

Low speed

Electromagnetic emission

Very high cost : **equivalent to it’s own weight in gold**

Repaint regularly

Special maintenance

• The Air Force held a demonstration and showed that 2 stealth aircrafts were equal to 75 non-stealth aircrafts.

• This is the present world’s one of the best advanced technology to make things invisible as far as possible and it is developing to be applied to the real life appliances as to a common man . Let us hope that it will develop to the more better way in the future.