The Falcon 9 version 1.1 features more powerful engines, a longer first stage to accommodate larger propellant tanks, a new payload fairing and a triply redundant flight computer system, improvements intended to boost the rocket's payload capability while improving safety and reliability.
The 224-foot-tall rocket also featured simplified stage attachment mechanisms, a new circular engine arrangement for the first stage and a beefed up first stage heat shield. The company eventually hopes to recover spent stages for refurbishment and reuse.
Given the multiple upgrades involved, Elon Musk, SpaceX's CEO and chief designer, said he considered the launching a test flight. Canada's 1,100-pound Cassiope space weather satellite, provided by MacDonald, Dettwiler and Associates, the Canadian Space Agency and the University of Calgary, reportedly got the ride for about $10 million.
"We don't consider this to be an operational launch," Musk told Spaceflight Now in a pre-launch interview. "It's a demo or a beta launch. Cassiope understands that. They got a pretty significant discount since this is a new Falcon 9."
The towering rocket's nine upgraded Merlin 1D first-stage engines ignited at 12 p.m. EDT, throttled up to a combined 1.3 million pounds of liftoff thrust and quicky pushed the slender booster away from Space Launch Complex 4-East at Vandenberg Air Force Base northwest of Los Angeles.
Once used by Air Force heavy-lift Titan 4 rockets, the launch pad was extensively modified by SpaceX in a $100 million makeover, providing a launch site for payloads that must be delivered into polar orbits. SpaceX also operates a launch complex at the Cape Canaveral Air Force Station in Florida for payloads that require more equatorial orbits.
The Falcon 9 is designed to achieve orbit even if two of the first-stage engines fail in flight, but all nine Merlin 1Ds appeared to fire normally during the booster's climb away on a southerly trajectory over the Pacific Ocean.
The first stage burned out and fell away about two minutes and 50 seconds after liftoff. The rocket's single-engine second stage then continue the drive to space, burning another six minutes before shutting down around eight minutes and 54 seconds after launch.
A crowd of SpaceX employees gathered at the company's Hawthorne, Calif., factory burst into cheers and applause.
"It was an amazing flight," John Insprucker, Falcon 9 product manager, said in a company webcast. "So far, and there's tons of data coming back, it looks like it was a picture-perfect flight, everything was looking good, right down the middle of the track."
The flight plan called for the Cassiope space weather satellite to be released about five minutes later into a planned orbit with a high point of around 930 miles and a low point of about 185 miles.
Three small "cubesats" making up the Polar Orbiting Passive Atmospheric Calibration Spheres, or POPACS, then were to be ejected from a dispenser a few minutes later. The mission is sponsored by Utah State University, Planetary Systems Corp. and Drexel University. Confirmation of the satellite releases was expected later in the day.
The rocket's other two satellites were expected to be deployed a few minutes after that. The 51-pound CUsat navigation research satellite was built by students at Cornell University. A 110-pound atmospheric probe known as DANDE, for Drag and Atmospheric Neutral Density Explorer, was provided by the University of Colorado at Boulder.
SpaceX developed the Falcon 9 as a purely commercial venture to boost civilian and military satellites into space along with company-designed Dragon cargo ships built to carry supplies and equipment to and from the International Space Station.
SpaceX holds a $1.6 billion contract with NASA for at least 12 station resupply missions to deliver some 44,000 pounds of cargo and supplies.
Prior to Sunday's flight, SpaceX had successfully launched five Falcon 9s using first-stage Merlin 1C engines generating just under 900,000 pounds of sea-level thrust. Two Dragon test flights and two operational space station resupply missions have been launched to date.
SpaceX also is participating in a NASA competition, along with Boeing and Sierra Nevada, to develop a commercial manned spacecraft to ferry crews to and from the space station.
Musk hopes to use the Falcon 9 v1.1 and an upgraded manned version of the Dragon cargo ship to provide low-cost transportation to low-Earth orbit. The rocket also can be used for heavier commercial and military satellites.
The v1.1 modifications start at the base of the rocket where the new engines are arranged in a circular "octaweb" pattern with eight powerplants surrounding a central engine. The earlier version had the engines arranged in a square 3-by-3 arrangement, requiring aerodynamic panels around the base of the rocket.
In the new version, protective panels were installed between the engines to prevent a malfunctioning engine from damaging another. The first stage also features longer propellant tanks a heat shield.
For the initial test flight, engineers planned to restart the first stage engines as it fell back to Earth to slow it down before plunging back into the thick lower atmosphere. The stage was not designed to be recovered, but Musk plans to collect data on every flight to perfect an eventual recovery system.
"I give pretty low odds of this recovery working on this flight," Musk told Spaceflight Now. "The point of this mission is demonstrating the ascent of the crewed version of the Falcon 9."
The v1.1 version of the Falcon 9 is the company's first to feature a payload fairing that can encapsulate large satellites. The fairing separated and fell away as planned just after the second stage ignited.
Another major upgrade was a triply redundant flight computer running new software. Musk said the new computer system was extremely robust.
"You could put a bullet hole in any one of the avionics boxes and it would just keep flying," Musk told Spaceflight Now.
Other improvements include a simpler, more reliable mechanisms to connect the rocket's stages, using three connectors in place of nine.
The new Merlin 1D engines feature more efficient fuel injectors and weigh in at under 1,000 pounds each. The company said improvements in robotic manufacturing techniques, along with fewer parts make the engines easier to build and improve reliability.