CEO: Engines likely behind failed launch

On what was to be a resupply mission to the International Space Station, an unmanned NASA-contracted rocket exploded seconds after launch Tuesday, October 28, on the coast of Virginia. The launchpad was damaged, but no one was injured.

An aerial view shows damage to the Wallops Island, Virginia, launch facility following the rocket's explosion.

People who came to Wallops Island to watch the launch walk away after the unmanned rocket, owned by Orbital Sciences Corp., exploded.

The rocket and spacecraft -- which together cost more than $200 million, according to Frank Culbertson, the general manager of Orbital's Advanced Programs Group -- are gone.

The rocket had been set to go up Monday, only to be scrubbed "because of a boat downrange in the trajectory Antares would have flown had it lifted off," according to NASA. Coast Guard spokesman David Weydert said the boat that triggered the postponement was 40 miles offshore. Tuesday, by contrast, seemed perfect. Just before liftoff, NASA reported "100% favorable" weather and "no technical concerns with the rocket or spacecraft being worked."

The Antares rocket, with the Cygnus spacecraft on board, is seen on Launch Pad-0A after the launch attempt was scrubbed on October 27.

The Orb-3 mission's payload fairing (essentially the casing around the spacecraft) was installed on the Antares on October 23.

The payload fairing goes onto the spacecraft. Orbital will lead the investigation of the accident, along with the FAA, with NASA assisting. Among other things, they'll try to collect and examine any debris that can be recovered, review data from the spacecraft before its destruction and look at videos around the launch time.

• Evidence indicates an engine failed 15 seconds after ignition, Orbital's CEO says


• The turbo pump in one of the engines likely failed, he says


• Orbital Sciences still plans to stay on track with its $1.9 billion NASA contract, he says

(CNN) -- Decades-old Russian engines are believed to have caused the Antares rocket's failure to launch properly, Orbital Sciences Corp.'s CEO David Thompson said Wednesday.

"Current evidence strongly suggest that one of the two AJ26 main engines that powered Antares' first stage failed about 15 seconds after ignition," Thompson said in a conference call with investors.

Last week, a company spokesman said the unmanned rocket, which exploded in a fireball at NASA's Wallops Flight Facility in Virginia, was deliberately destroyed after it became apparent there was a problem.

The turbo pump in one of the engines likely failed, Thompson said Wednesday. Orbital will likely stop using these engines, he said, since they have proven to be unreliable.

The Antares rocket and Cygnus cargo spacecraft had been set to carry roughly 5,000 pounds of supplies and experiments to the International Space Station.

Despite what Thompson described as a "setback," the company plans to stay on track with its $1.9 billion NASA contract delivering cargo to the space station, he said.

Orbital hopes to launch its Cygnus spacecraft using third-party rockets, he said.

There are three companies in the running: two from the United States and one from Europe.

Thompson would not reveal which companies, but said a decision is expected within a month.

SpaceX and United Space Alliance, the two likely U.S. companies -- operate regular launches at Cape Canaveral Air Force Station in Florida. Orbital Sciences, SpaceX and the Russians' Soyuz all regularly fly cargo and supplies to the six astronauts and cosmonauts stationed on the space station.

While using another company's launch vehicle, Orbital will concentrate on replacing the 1970s-era Russian engines by 2016.

Thompson thanked NASA for its support.

"We look forward to working closely with them to quickly recover from last week's setback," he said.