The Nanda Kot device returned data for several months before failing, and a climbing team recovered it in the summer of 1968.
Notes on verification
Confirmed by multiple independent sources including Wikipedia, The Wire (citing M.S. Kohli's writings), and Live History India. Minor wording variations exist but core facts—device operating for months then failing, retrieval in summer 1968—are consistent across sources.
Sources
- How the United States Lost a Nuclear Device and Recovered an Indian Friend (warontherocks.com)
- https://m.thewire.in/article/security/inside-the-nanda-devi-nuclear-spy-mission-what-the-nyt-revisited-and-what-it-missed/amp (m.thewire.in)
- https://www.livehistoryindia.com/story/eras/nanda-devi-nuclear-device (livehistoryindia.com)