Monday, October 8, 2012

SpaceX Makes History -- With Unintended Consequences


Click the arrow to watch a SpaceKSC.com video of the October 8, 2012 SpaceX launch as viewed from NASA Causeway.

A perfect countdown resulted in a perfect launch for SpaceX — until 79 seconds into the flight.

SpaceX made history Sunday night by launching the first commercial cargo flight to the International Space Station. The mission has political overtones, as it can be viewed as vindication of the Obama administration's strategy to privatize cargo and crew delivery services to Low Earth Orbit.

The Obama re-election campaign issued a congratulatory statement and took credit for its policy success:

When President Obama came into office, he inherited a program in crisis from an administration that promised the retirement of the Space Shuttle that had become the long standing symbol for exploration and scientific innovation. President Obama knew the United States could do better, and made bold steps by taking immediate action to put NASA on a path for a sustainable future, one that is critical for Florida's Space Coast and essential for continued U.S. leadership in space. Now, because of President Obama's efforts, the International Space Station has an extended life, there is growth in the country's commercial space industry, and a promise to continue a commitment of human exploration, science, and other aeronautic programs.

The e-mail press release was time-stamped 9:00 PM EDT, 25 minutes after the launch.

What was not clearly known at the time was that the launch suffered what in the space business is called an "anomaly."


Click the arrow to watch slow-motion video of the Merlin 1C engine failure.

It appeared that one of the nine Merlin 1C engines on the Falcon 9 exploded at 79 seconds after launch. The other eight engines compensated for the failure and the mission continued.

After a morning of rampant Internet speculation and rumor-mongering, SpaceX finally issued a statement:

Approximately one minute and 19 seconds into last night's launch, the Falcon 9 rocket detected an anomaly on one first stage engine. Initial data suggests that one of the rocket's nine Merlin engines, Engine 1, lost pressure suddenly and an engine shutdown command was issued. We know the engine did not explode, because we continued to receive data from it. Panels designed to relieve pressure within the engine bay were ejected to protect the stage and other engines. Our review of flight data indicates that neither the rocket stage nor any of the other eight engines were negatively affected by this event.

As designed, the flight computer then recomputed a new ascent profile in real time to ensure Dragon's entry into orbit for subsequent rendezvous and berthing with the ISS. This was achieved, and there was no effect on Dragon or the cargo resupply mission.

Falcon 9 did exactly what it was designed to do. Like the Saturn V (which experienced engine loss on two flights) and modern airliners, Falcon 9 is designed to handle an engine out situation and still complete its mission. No other rocket currently flying has this ability.

It is worth noting that Falcon 9 shuts down two of its engines to limit acceleration to 5 g's even on a fully nominal flight. The rocket could therefore have lost another engine and still completed its mission.

We will continue to review all flight data in order to understand the cause of the anomaly, and will devote the resources necessary to identify the problem and apply those lessons to future flights. We will provide additional information as it becomes available.

Other rumors continue to circulate. One is that the Orbcomm secondary payload failed to deploy in its proper orbit. Another is that the Falcon 9's second stage engine failed to restart. And another is that the Dragon's Guidance and Navigation Computer door failed to open, although that one apparently has been debunked.

Private companies are not in the habit of addressing endless rumors. We are experiencing a cultural adjustment where fifty years of space launches conducted publicly are now performed by the private sector.

But NASA was guilty of "spin" in the early days after the Challenger and Columbia disasters, so there's no reason to think human behavior would be any different, public or private, when the unexpected happens.

The Merlin 1C is scheduled for replacement by the 1D in 2013, so if there was a design flaw or other concern it may be irrelevant once the 1D enters service.

The Dragon capsule, meanwhile, heads for its next rendezvous with history. Hopefully we've seen the last of the anomalies for Cargo Resupply Services-1.


UPDATE October 8, 2012 7:45 PM EDTOrbcomm issued a press release this afternoon detailing the status of its prototype satellite.

The OG2 prototype satellite, flying as a secondary payload on this mission, was separated from the Falcon 9 launch vehicle at approximately 9:00 pm EST. However, due to an anomaly on one of the Falcon 9’s first stage engines, the rocket did not comply with a pre-planned International Space Station (ISS) safety gate to allow it to execute the second burn. For this reason, the OG2 prototype satellite was deployed into an orbit that was lower than intended. ORBCOMM and Sierra Nevada Corporation engineers have been in contact with the satellite and are working to determine if and the extent to which the orbit can be raised to an operational orbit using the satellite’s on-board propulsion system.

No comments:

Post a Comment