File photo of APJ Abdul Kalam.

The sudden demise of former president A P J Abdul Kalam was a tremendous loss to the country, Indian space agency chief A S Kiran Kumar said on Monday.Dr Kalam, 83, passed away in Meghalaya capital Shillong on Monday evening.Kiran Kumar said the former president was a great personality and gentleman."It is extremely sad to know that Kalam is no more. He was such a great personality and a gentleman. No words to express," the Indian Space Research Organisation (ISRO) chairman said.Terming Dr Kalam's contribution to the country and humanity as great and immense, Kiran Kumar said that even at the age of 84 years, the missile man was thinking about finding better solutions for the country's energy requirements.Kiran Kumar recalled his last meeting with Dr Kalam at Raj Bhavan in Bengaluru a month ago. He said that he had met Dr Kalam on many occasions when he was the president."Though I was in Ahmedabad as director of the space applications centre, I had many opportunities to meet and interact with Kalam sir at official functions and public events," he said.