In 1970, he was also tasked by Indira Gandhi to prepare a classified feasibility study for building long-range ballistic missiles. Based on Nagchaudhuri's recommendation, Project Valiant was initiated in 1972 to build a liquid-fuelled intermediate range ballistic missile. Another initiative, Project Devil, was initiated at the Defense Research & Development Laboratory (DRDL) to produce short-range surface-to-air missiles. While both projects were terminated in 1974 due to conflicts within DRDL and resulting lack of progress, they laid the foundation for the successful Integrated Guided Missile Development Program in the early 1980s.