SpaceX postpones rocket recovery launch

US private spaceflight company SpaceX Tuesday aborted a rocket launch, which would have led to an experiment to bring a part of the rocket to a soft landing on a floating sea platform.

The scheduled launch of the Falcon 9 rocket was aborted Tuesday. The firm had planned to bring back the first stage of the rocket for possible future re-use.

The decision to abort the mission was related to a technical problem detected in the steering mechanism of the rocket's upper stage.

The next possible launch attempt was postponed till Friday "pending resolution of the issue", media reported citing a NASA tweet.

The primary purpose of the flight is to send the Dragon cargo ship on a rendezvous with the International Space Station (ISS), BBC reported.

It will be the first US re-supply mission to the orbiting platform since October's explosion of a freighter system operated by competitor Orbital Sciences Corporation.

SpaceX believes it can return, refurbish and re-use key elements of its rockets.

Once the first stage of the rocket launches, and has finished its work, it will head back to the Earth to try to touch down on a sea barge on the Atlantic Ocean.

If this kind of capability can be proven, it promises to dramatically lower launch costs in the future.

All segments of a rocket are usually discarded after use and are destroyed as they fall back down.

SpaceX, however, has been practising the controlled return of the first stage of its Falcon 9 vehicle.

It has been testing first-stage boosters that re-light their engines to slow down their fall through the atmosphere, attaching fins to help guide them downwards, and legs to make a stable touchdown.

SpaceX itself has been playing down expectations, rating the chances of success at no more than 50 percent.

"I'm pretty sure this will be very exciting, but, as I said, it's an experiment," cautioned Hans Koenigsmann, vice-president for mission assurance at SpaceX.

"There's a certain likelihood that this will not work out all right, that something will go wrong. It's the first time we have tried this -- nobody has ever tried it as far as we know."

So far, there have only been mock landings, in which a rocket's first stage is brought to a hovering position at the surface of the ocean, where, without a solid platform to set down, every booster has subsequently been lost in the water.

Friday's effort will be different in that SpaceX has sent a floating barge to the targeted return site some 300 km northeast of Cape Canaveral, Florida.