Gaganyaan test flight delay: Will it stall India’s first human spaceflight launch?

ISRO chairman said the space agency had a key role to play in the success of Operation Sindoor, Axiom Mission 4.

The wait for Gaganyaan mission’s manned flight may just get a little longer.

The first uncrewed test flight for the Gaganyaan mission — ahead of the proposed maiden Indian human space flight launch — could be pushed back up to the third quarter of 2027, ISRO chairman V Narayanan indicated on Saturday even as he stressed that efforts were on for a launch by the end of 2026.

With this, the launch of Gaganyaan mission’s manned flight could be pushed back to 2028, as against 2027-end that the Indian Space Research Organisation (ISRO) had indicated earlier this year.

“The Gaganyaan programme is a very important technology intensive mission and human safety is very important. We are already working on this programme for the launch of a human-rated rocket and keeping the people in a safe environment because in case there is any problem with the rocket, we have to save the crew…” the ISRO chairman said.

Delivering the Air Marshal L M Katre Memorial Lecture organised by the Air Force Association in Bengaluru, the ISRO chairman, who is also the secretary of the Department of Space, indicated on a slide in his presentation that the first unmanned flight for the Gaganyaan mission would be launched in the third quarter of 2027.

However, in his talk on the “Indian Space Programme – The Challenges and Way Forward”, Narayanan stated that the uncrewed mission could happen in 2026 as well.

“We are supposed to do three uncrewed missions: We are working for the first uncrewed mission this year and once we get the results, we will get back to the crewed mission. The Gaganyaan continuation programme has been approved by the government. Earlier, only the uncrewed missions and one crewed mission were approved,” the ISRO chief said.

When asked about the two differing timelines — one indicated in his presentation and the other during the talk itself — for the first unmanned flight, the ISRO chairman said, “The Gaganyaan programme is undergoing constant review and the first unmanned flight will be launched on the basis of the progress.”

In February, Narayanan had indicated that the first Indian manned mission to space could be launched by end of 2027.

During the talk on Saturday, the ISRO chairman said Indian scientists played a key role in the safe flight of the Axiom Mission 4 launched in June 2025 on a SpaceX rocket, which took Indian astronaut Shubhanshu Shukla to the International Space Station in 2025.

“We had a big role in the safe journey… The SpaceX rocket was set to launch (on June 11) and on June 10, we came to know there was a minor leakage problem with the rocket. We discussed the issue and they (American scientists) said it is only a minor problem and that the rocket can take off. It was Indian scientists, including myself and my team, and the director of Human Space Flight Centre D K Singh was also there at the Kennedy Space Centre, who insisted that the launch should be stopped and it was stopped,” he said.

“Finally, when it was inspected, there was a crack in one of the mainline and it was eventually corrected and the launch took place on June 25, 2025,” the ISRO chief said.

“We have proven to the world that the Indian education system is second to none, that the Indian training is second to none even if we have to hold back a human-rated rocket at the last minute,” Narayanan said.

The ISRO chairman also touched upon recent setbacks, including two successive failures of the workhorse PSLV rockets in 2025 and 2026 and sub-optimal functioning of the indigenous Navigation with Indian Constellation (NavIC) satellites which have been reduced to three satellites against an optimum of four satellites.

“We have had two setbacks on PSLV and today, I am happy to inform you that we have understood everything and we are in the process of coming back. A space mission is like a long jump mission to cross a well of 1.5 metre diameter. If you say you have jumped 98% of the distance then it means you have fallen in the well. A space mission is zero or 100%. We have to be 100 on 100,” the ISRO chairman said.

On the NavIC programme, Narayanan said efforts were underway to bring the constellation of satellites to an optimum level.

“In terms of strategic applications during Operation Sindoor, I cannot make open statements, but surely I can say that all our satellites worked perfectly well and we did whatever small work we could contribute for Operation Sindoor,” Narayanan said.

“In the success of Operation Sindoor, we had a key role to play,” he added.

One of the areas of significant progress for ISRO in recent years has been in the innovations linked to the propulsion systems for the ISRO rockets, Narayanan said. “In rocket systems for launch vehicles, which will place a Chandrayaan 3 in a deep space orbit, we need a speed of 37,000 km/hr. The rocket should be capable of such speeds,” he said.

“We have developed a cryogenic rocket engine — a technology which was denied to India — which is a 20 tonne engine. To generate a 20 tonne thrust with an aircraft engine, you need 1,000 kg per second of fuel to be pumped inside. We cannot carry such a large quantity of rocket fuel because the rocket will not take off. In the cryogenic engines we get the 20 tonne thrust by consuming only 45 kg per second of fuel,” Narayanan said.

The wait for Gaganyaan mission’s manned flight may just get a little longer.

The first uncrewed test flight for the Gaganyaan mission — ahead of the proposed maiden Indian human space flight launch — could be pushed back up to the third quarter of 2027, ISRO chairman V Narayanan indicated on Saturday even as he stressed that efforts were on for a launch by the end of 2026.

With this, the launch of Gaganyaan mission’s manned flight could be pushed back to 2028, as against 2027-end that the Indian Space Research Organisation (ISRO) had indicated earlier this year.

“The Gaganyaan programme is a very important technology intensive mission and human safety is very important. We are already working on this programme for the launch of a human-rated rocket and keeping the people in a safe environment because in case there is any problem with the rocket, we have to save the crew…” the ISRO chairman said.

Delivering the Air Marshal L M Katre Memorial Lecture organised by the Air Force Association in Bengaluru, the ISRO chairman, who is also the secretary of the Department of Space, indicated on a slide in his presentation that the first unmanned flight for the Gaganyaan mission would be launched in the third quarter of 2027.

However, in his talk on the “Indian Space Programme – The Challenges and Way Forward”, Narayanan stated that the uncrewed mission could happen in 2026 as well.

“We are supposed to do three uncrewed missions: We are working for the first uncrewed mission this year and once we get the results, we will get back to the crewed mission. The Gaganyaan continuation programme has been approved by the government. Earlier, only the uncrewed missions and one crewed mission were approved,” the ISRO chief said.

When asked about the two differing timelines — one indicated in his presentation and the other during the talk itself — for the first unmanned flight, the ISRO chairman said, “The Gaganyaan programme is undergoing constant review and the first unmanned flight will be launched on the basis of the progress.”

In February, Narayanan had indicated that the first Indian manned mission to space could be launched by end of 2027.

During the talk on Saturday, the ISRO chairman said Indian scientists played a key role in the safe flight of the Axiom Mission 4 launched in June 2025 on a SpaceX rocket, which took Indian astronaut Shubhanshu Shukla to the International Space Station in 2025.

“We had a big role in the safe journey… The SpaceX rocket was set to launch (on June 11) and on June 10, we came to know there was a minor leakage problem with the rocket. We discussed the issue and they (American scientists) said it is only a minor problem and that the rocket can take off. It was Indian scientists, including myself and my team, and the director of Human Space Flight Centre D K Singh was also there at the Kennedy Space Centre, who insisted that the launch should be stopped and it was stopped,” he said.

“Finally, when it was inspected, there was a crack in one of the mainline and it was eventually corrected and the launch took place on June 25, 2025,” the ISRO chief said.

“We have proven to the world that the Indian education system is second to none, that the Indian training is second to none even if we have to hold back a human-rated rocket at the last minute,” Narayanan said.

The ISRO chairman also touched upon recent setbacks, including two successive failures of the workhorse PSLV rockets in 2025 and 2026 and sub-optimal functioning of the indigenous Navigation with Indian Constellation (NavIC) satellites which have been reduced to three satellites against an optimum of four satellites.

“We have had two setbacks on PSLV and today, I am happy to inform you that we have understood everything and we are in the process of coming back. A space mission is like a long jump mission to cross a well of 1.5 metre diameter. If you say you have jumped 98% of the distance then it means you have fallen in the well. A space mission is zero or 100%. We have to be 100 on 100,” the ISRO chairman said.

On the NavIC programme, Narayanan said efforts were underway to bring the constellation of satellites to an optimum level.

“In terms of strategic applications during Operation Sindoor, I cannot make open statements, but surely I can say that all our satellites worked perfectly well and we did whatever small work we could contribute for Operation Sindoor,” Narayanan said.

“In the success of Operation Sindoor, we had a key role to play,” he added.

One of the areas of significant progress for ISRO in recent years has been in the innovations linked to the propulsion systems for the ISRO rockets, Narayanan said. “In rocket systems for launch vehicles, which will place a Chandrayaan 3 in a deep space orbit, we need a speed of 37,000 km/hr. The rocket should be capable of such speeds,” he said.

“We have developed a cryogenic rocket engine — a technology which was denied to India — which is a 20 tonne engine. To generate a 20 tonne thrust with an aircraft engine, you need 1,000 kg per second of fuel to be pumped inside. We cannot carry such a large quantity of rocket fuel because the rocket will not take off. In the cryogenic engines we get the 20 tonne thrust by consuming only 45 kg per second of fuel,” Narayanan said.