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TheSkulker wrote:It's getting almost boring watching an Elon Musk/Falcon 9 launch.

No drama: No holds. No oopsies. No abnormal readings. Just "nominal" condition switchovers, calm announcements: "TFS initiated", "switching to internal power", "the engines will fire at T-3", etc. The commentator had to work hard to keep the audience's attention. Even the weather was perfect. I guess that is what happens when you have a genius techie who is also a good leader with a philosophy of not unnecessarily reinventing the wheel and who prizes simplicity, safety and reliablity designing a rocket and running the show. Ah well, we will just have to get used to a boring, accelerated pace of exploring space.

Short launch clip:

NBCNews.com wrote:Some observers pointed to SpaceX's long-range video of the ascent and pointed to what they thought was debris from an explosion. Today, SpaceX issued a statement saying that the engine didn't explode — but that protective panels were ejected because of the pressure loss associated with the shutdown:

"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.

"Dragon is expected to begin its approach to the station on October 10, where it will be grappled and berthed by Akihiko Hoshide of the Japan Aerospace Exploration Agency and Expedition 33 Commander Sunita Williams of NASA. Over the following weeks, the crew will unload Dragon's payload and reload it with cargo to be returned to Earth. Splashdown is targeted for October 28."

Space News International wrote: Space Exploration Technologies (SpaceX) Corp. acknowledged that its Falcon 9 rocket experienced an engine anomaly during its December launch of the company’s reusable Dragon space capsule.

“I’d call it an oxidizer-rich shutdown,” former NASA astronaut Ken Bowersox, SpaceX’s vice president of astronaut safety and mission assurance, told Space News in a Sept. 9 interview. “So because of that, when you get that mixture change happening, the temperatures can go up higher than you want inside the gas generator.”

Bowersox added that “those temperatures could have damaged the turbines in the turbopump.” That presents an obstacle for SpaceX, which eventually intends to reuse the nine Merlin engines that power the Falcon 9.

It does not, however, present an obstacle for cargo delivery missions to the international space station, SpaceX said.

An oxygen-rich shutdown is “not a catastrophic event for the Merlin engine,” Bowersox said. “We’ve been through this on the test stand and we know what it looks like for our engines, so we know that this was not a risk to the mission.”

Indeed, despite the engine anomaly, Falcon 9 successfully delivered Dragon to orbit during the Dec. 8 mission, an orbital demonstration flight conducted under NASA’s Commercial Orbital Transportation Service (COTS) program.

SpaceX spokeswoman Kirstin Brost Grantham said that the anomaly poses no threat to the company’s upcoming COTS demonstration, a flight to the international space station (ISS) targeted for late November. If that flight goes well, SpaceX would begin making periodic supply runs to the ISS under a $1.6 billion contract NASA awarded the Hawthorne, Calif.-based company in 2008.

Bowersox’s acknowledgement to Space News that the Falcon 9’s main stage experienced an oxygen-rich shutdown came after a discussion of the incident during a joint meeting of the ISS Advisory Committee and the NASA Safety Advisory Panel at NASA headquarters here earlier the same day. The meeting was held to discuss the results at an Aug. 9 meeting with SpaceX and Orbital Sciences Corp., another company under contract to fly cargo to the ISS.

During the August meeting, held at the Johnson Space Center in Houston, SpaceX told the two advisory bodies that there had been an engine anomaly during the most recent Falcon 9 launch, said Charles Daniel, a shuttle and space station safety expert at Herndon, Va.-based Valador Inc., and a member of the ISS Advisory Committee.

“There was no explanation or root cause analysis or corrective action for this particular anomaly,” Daniel said Sept. 9 during the public meeting. “This is a relatively troublesome statement not to recognize that a premature engine shutdown was a significant event.”

SpaceX disputes Daniel’s characterization of the engine anomaly as a premature shutdown.

“We did not have a premature engine shutdown,” Bowersox told Space News.

Bowersox also said SpaceX informed NASA of the engine anomaly right away.

“This information was presented to NASA and to the [Federal Aviation Administration] not too long after the mission,” Bowersox said. “But it didn’t go to the Aerospace Safety Advisory Panel, it went to some of the different NASA programs that we work with.”

SpaceX spokesman Robert Block said that NASA received a briefing about the flight Dec. 15. SpaceX subsequently delivered full-rate telemetry for the flight on Dec. 28. A full flight report to the agency followed on Feb. 24, Block said.

Another question has yet to be fully resolved: What will happen to the Orbcomm OG2 telecommunication satellite, which rode into orbit as a secondary payload on the Falcon 9's second stage? The prototype satellite was supposed to be put into a highly inclined orbit after a second-stage restart, and serve as the first piece of a new 18-satellite telecom constellation.

On Sunday night, SpaceX said the satellite was "successfully deployed" — but Orbcomm acknowledged in a statement today that the satellite was deployed into the wrong orbit because of the engine anomaly. Here's the relevant excerpt:

"... 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 Corp. 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.

"In mid-2013, Orbcomm plans to launch an additional eight OG2 satellites on a Falcon 9, which will be placed into orbits that are optimized to deliver the best coverage for the enhanced OG2 messaging services. The remainder of the constellation of 18 OG2 satellites is expected to be launched on a Falcon 9 in 2014. Orbcomm’s OG2 satellites will be the primary payload on both of these two planned launches to directly insert the OG2 satellites into the operational orbit."

Orbcomm's statement came after satellite-watcher Jonathan McDowell called attention to the fact that the satellite showed up in the Space-Track database as having a 203-by-323-kilometer orbit rather than the planned 350-by-750-kilometer orbit.

shadowinthelight wrote:The radio report I heard said one of the engines lost fuel(?) pressure and failed, not exploded. Did they change the story afterward?

bmonk wrote:I think it's rocket science--and beyond me...

MerchManDan wrote:

bmonk wrote:I think it's rocket science--and beyond me...

At least it isn't brain surgery.

NOTDilbert wrote:

MerchManDan wrote:

bmonk wrote:I think it's rocket science--and beyond me...

At least it isn't brain surgery.

Or rocket surgery.....

Fairportfan wrote:"All right, Mr Smith, you have a benign tumor in your upper digestive tract. We're going to try a new procedure to remove it - we'll be firing a small rocket with a teeny little explosive charge and a seeker head up your butt under a local anesthetic..."

Jabberwonky wrote:

Fairportfan wrote:"All right, Mr Smith, you have a benign tumor in your upper digestive tract. We're going to try a new procedure to remove it - we'll be firing a small rocket with a teeny little explosive charge and a seeker head up your butt under a local anesthetic..."

NOTHING good can come from butt rockets...

NOTDilbert wrote:

Jabberwonky wrote:

Fairportfan wrote:"All right, Mr Smith, you have a benign tumor in your upper digestive tract. We're going to try a new procedure to remove it - we'll be firing a small rocket with a teeny little explosive charge and a seeker head up your butt under a local anesthetic..."

NOTHING good can come from butt rockets...

Wasn't there something like that in an ep of the old Jetsons cartoon?

Jabberwonky wrote:

Fairportfan wrote:"All right, Mr Smith, you have a benign tumor in your upper digestive tract. We're going to try a new procedure to remove it - we'll be firing a small rocket with a teeny little explosive charge and a seeker head up your butt under a local anesthetic..."

NOTHING good can come from butt rockets...