Kerala: Former ISRO chief G Madhavan Nair said Saturday's successful launch of the Indian space agency's unmanned test flight of 'Mission Gaganyaan' was a "significant milestone" for India's programme to put humans in space in the near future.

"I am really happy to learn that the TV-D1 mission of ISRO has been successfully completed today..." Nair told ANI today.

Today's test flight (Test Vehicle D1 Mission) was conducted to test the emergency escape system of its crew module, which separated from the thruster and made a soft sea landing about 10 minutes after the launch.

The Test Vehicle D1 mission was launched on the second attempt at 10 am today after it faced an engine ignition problem at 8:45 am. It was intially scheduled for a lift-off from the first launch pad at 8 am that was revised to 8.45 am and later to 10 am.

The former ISRO chairman elaborated that the the first postponement, an about 40 minute delay was caused due to bad weather in Sriharikota and subsequently when the launch was attempted the automated launch system issued an abort command a few seconds before lift-off.

"The computer detected some anomaly condition and that led to abort of the mission at that instant. The ISRO team has carefully analysed all the parameters of the computers. By 10 am, they were able to attempt a launch again after correcting the anomaly, Nair said.

The TV-D1 flight lifted off from Sriharikota in its second attempt in the mission, which according to ISRO was conducted to "test the efficiency of the vehicle's crew escape system."

"The vehicle went slightly above the speed of sound, before it initiated the crew escape system," the current ISRO chief Somanath said.

"The escape system took the crew module away from the vehicle and subsequent operations including the touch-down at the sea have been very well accomplished," he added.

Elaborating on the launch vehicle, Madhavan Nair said it is a special purpose vehicle developed around the Vikas (rocket engine), which is part of the "well proven" GSLV rocket system.

Today's flight has "taken the man capsule to an altitude of nearly 10 kilometres and to a velocity of 1.2 times the velocity of sound."

"At that instant the crew module was ejected from the mother vehicle using a set of rocket system and taken through a different trajectory to have a safe landing in the Bay of Bengal," Nair said.

"The entire sequence of events" of the flight "including the separation and the new trajectory opening up of the parachutes and finally landing in sea has been demonstrated," he said. Nair said that a detailed investigation will point out what went wrong.

"From what I understand, the TV-D1 mission was temporarily suspended due to some last-minute glitch. If any anomaly is observed in any of these systems, the computer will automatically hold the launch, and it will be virtually saving the mission. So here exactly the same thing happened," he added.

ISRO chief Somanath congratulated scientists after the successful touchdown of the crew escape module.

On the occasion, Mission Director S Sivakumar said, "This is like a never before attempt. It is like a bouquet of three experiments put together.

"We have now seen the characteristics of all three systems with what we wanted to test through this experiment or this mission. The test vehicle, the crew escape system, the crew module everything, we have perfectly demonstrated in the first attempt. All the systems performed well," Sivakumar said.

The mission objectives of the TV-D1 launch were flight demonstration and evaluation of Test Vehicle subsystems; flight demonstration and evaluation of Crew Escape System including various separation systems; crew module characteristics; and deceleration system demonstration at higher altitudes and its recovery.

The Gaganyaan project envisages a human spaceflight capability by launching a crew of three members into an orbit of 400 km for a 3-day mission and bringing them safely back to earth by landing in Indian waters.

This programme will make India the fourth nation to launch a manned spaceflight mission after the US, Russia, and China.

Building on the success of the Indian space initiatives, including the recent Chandrayan-3 and Aditya L1 missions, Prime Minister Narendra Modi directed that India should now aim for new and ambitious goals, including setting up 'Bharatiya Antariksha Station' (Indian Space Station) by 2035 and sending the first Indian to the Moon by 2040.