Last-second abort grounds first flight of Indian rocket

Posted: March 28, 2001

The GSLV rocket on the launch pad. ISRO
India's newest rocket was one second away from launch Wednesday on its inaugural flight when computers detected a malfunctioning engine and aborted the liftoff.

The demonstration flight of the Geosynchronous Satellite Launch Vehicle was slated to begin at 1017 GMT (5:17 a.m. EST) from the Sriharikota complex along the Indian east coast with the GSAT-1 experimental communications satellite aboard.

But that was not to be.

As the countdown clock passed T-minus 4.6 seconds, the four liquid-fueled boosters strapped to the rocket's first stage began to ignite. The Vikas engines are supposed to build up thrust while computers verify the powerplants are functioning properly.

If there are no problems, the solid-fueled first stage would then fire to life to lift the rocket skyward.

On Wednesday, however, one of the four strap-on stages failed to generate the required minimum level of thrust of 90 percent.

The trouble was spotted by control computers, which automatically stopped the countdown with one second to spare and commanded the four engines to shut down. The abort occurred safely before the first stage motor ignited.

The nail-biting abort caught spectators by surprise. As the countdown ticked off the final moments, the launch commentator accidently announced the launch, exclaiming: "And we have lift off!"

Of course the vehicle didn't lift off, but a flash of flame was noted as the engines were shutting down.

An overhead view shows the four strap-on boosters being mounted to GSLV rocket's first stage. ISRO
Launch officials are investigating the situation to determine what went wrong. A new launch date is not expected until after engineers understand what caused the problem.

"These are all part and parcel of this kind of game," Reuters quoted Indian Space Research Organization (ISRO) Chairman K. Kasturirangan as saying at a post-scrub press conference. "We have decided that the mission is cancelled for the time being."

It is not known what will need to take place before the vehicle is ready for another launch attempt. After launches are aborted while the engines are firing, technicians either replace the spent powerplants for fresh ones or perform a thorough re-certification process.

The Vikas engines on the GSLV's strap-on boosters are similar to the Viking engines used on European Ariane 4 rockets. In fact, a lot of the technology used on the GSLV comes from older Indian launchers and other nations. For example, Russia provided the RD-56M engine used on the GSLV's cryogenic third stage.