DRDO Anti-Radiation Missile by the Indian government In February 2016, it was reported that captive flight trials of anti-radiation missile are planned for April–May this year, and the maiden flight test by year–end by the missile technologists of the DRDO. According to DRDO sources, scientists will evaluate the performance of the seeker, navigation and control system, structural capability and aerodynamic vibrations during the captive flight trials. These will be followed by ground testing and the missile will be fired from Sukhoi Su-30MKI during the actual flight trial by year-end. The missile will be inducted in about two years after conducting a number of
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