Ans. Stealth Technology is a technology that makes aircraft invisible or less visible to radars.
This technology involves superior design of aircraft and use of advanced material, paint coat etc. that make surface of aircraft less reflective. This also absorbs the electromagnetic waves produced by Radar. This technology was initially developed by the USA.
The key to the development of this technology is the use of ecospheres that are microscopic ceramic balls that absorb energy at radio or infrared frequency. The Defence Research and Development Organization have developed the stealth technology, by developing a special radar absorbent coat of paint which reduces radar image upto 70%.
An Indigenous Air Defence System has been developed by Defence Research and Development Organization. This indigenous defence system has centralized command, control and communication structure which is linked to several mission units (control units) throughout the country to detect all incoming missile and enemy aircraft.