After the change of guard and controversial decision to remove Agni-IV project director, preparations are afoot at the Defence Research and Development Organisation (DRDO) to test fire the Prithvi and Advanced Air Defence (AAD) interceptor missiles. A reliable source said, user trial of Army version of Prithvi weapon system is slated on February 21 while a developmental trial of endo-atmospheric (hitting the target inside the atmosphere) AAD interceptor missile is likely to be conducted in the first week of March. “The Strategic Forces Command (SFC) of the Army will carry out the test of Prithvi from the Integrated Test Range (ITR) at Chandipur-on-sea while the interceptor missile will be tested from the launching complex-IV located in Wheeler Island near Dhamra in Bhadrak district,” said the source. As per the programme, the interceptor missile will destroy an incoming hostile missile mid-flight over the Bay of Bengal. This experiment is being conducted to observe the operational effectiveness of the indigenously developed high-speed interceptor missile. During the test, a Prithvi missile, modified to mimic a hostile ballistic missile will lift off from the ITR and it would be destroyed in the endo-atmospheric region (at an altitude of less than 20 km) by the interceptor fired from Wheeler Island few seconds later. While Prithvi missile has already been inducted in the armed forces, a successful test of the AAD interceptor will pave the way for its induction. Yet to get a formal name, this hypersonic interceptor missile is meant to be used in ‘endo-atmospheric conditions’. Developed by DRDO, the 7.5 metre tall AAD interceptor is a single stage solid rocket propelled guided missile equipped with an inertial navigation system, a hi-tech computer and an electro-mechanical activator totally under command by the data up-linked from the ground based radar. The missile weighs around 1.2 tonnes and has a diameter of 0.5 metre. Defence sources said, elaborate preparations were on in the test range for the test launch of the surface-to-surface Prithvi missile. The nine metre tall missile with an extended range of more than 350 km can carry a payload of 1,000 kg. It has an accuracy of 10 to 50 metres and can be launched from Transporter erector launchers. Developed as a battlefield missile, it can carry a nuclear warhead in its role as a tactical nuclear weapon. Measuring one metre in dimension, the missile weighs around 4,600 kg. This particular test is aimed at achieving ‘close to zero’ circular error probability (CEP) accuracy.