DRDO Anti-Radiation Missile DRDO Anti-Radiation Missile The DRDO Anti-Radiation missile is a tactical, air-to-surface anti-radiation missile under development by India's Defence Research and Development Organisation. It is designed primarily to destroy enemy radars and communication facilities. This is a state-of-the-art air-to-surface anti-radiation missile being developed by Defence Research and Development Laboratory of the DRDO. The range of the missile is believed to be 100–125 km and it will be mounted on the combat aircraft of the IAF such as Sukhoi Su-30MKI and Tejas Light Combat Aircraft. The entire missile is being developed indigenously, including the seeker. According to the then Director of RCI,
Sound speed gradient Sound speed gradient In acoustics, the sound speed gradient is the rate of change of the speed of sound with distance, for example with depth in the ocean, or height in the Earth's atmosphere. A sound speed gradient leads to refraction of sound wavefronts in the direction of lower sound speed, causing the sound rays to follow a curved path. The radius of curvature of the sound path is inversely proportional to the gradient. When the sun warms the Earth's surface, there is a negative temperature gradient in atmosphere. The speed of sound decreases with decreasing temperature, so this also