(Adds landing test results, quotes from SpaceX's Elon Musk, paragraphs 7, 15-16)
By Irene Klotz
CAPE CANAVERAL, Fla., July 14 (Reuters) - Overcoming two months of delays, a Space Exploration Technologies' Falcon 9 rocket blasted off from Florida on Monday to put six small commercial communications satellites into orbit for ORBCOMM Inc .
The 224-foot (68-meter) tall rocket lifted off from a seaside launch pad at Cape Canaveral Air Force Station at 11:15 a.m. EDT (1515 GMT), darting through partly cloudy skies.
Launch had been delayed more than two months while privately owned SpaceX, as the company is known, wrestled with technical problems, weather and availability of the U.S. military's Eastern Range, which supports all launches from the Cape.
Aboard the rocket were six ORBCOMM Generation 2, or OG2, satellites, the first batch of a planned 17-member, $200 million network.
The rest of the network, which will beef up ORBCOMM's worldwide messaging services, will be launched aboard another Falcon 9 rocket later this year.
Monday's launch placed the six new satellites, built by privately owned Sierra Nevada Corp, into separate orbits about 500 miles (800 km) above Earth, where they joined an existing 25-member ORBCOMM network.
"All six ORBCOMM satellites deployed on target," SpaceX Chief Executive Officer Elon Musk said in a post on Twitter.
Each OG2 satellite has more capacity than the entire existing constellation, ORBCOMM Chief Executive Marc Eisenberg said in an interview.
In addition to handling longer messages between, for example, retailers and their shipping containers or construction companies and their cranes, OG2 will plug holes in the current system, making the network faster, he added.
Currently, ORBCOMM has gaps of about 30 minutes to an hour when satellites are out of range.
OG2 spacecraft are designed to last 10 years.
ORBCOMM is paying a cut-rate $43 million for two Falcon 9 flights and $4 million for two satellite-deployers made by Moog Inc. ORBCOMM originally bought rides on SpaceX's smaller Falcon 1 boosters, but those rockets were retired in 2009. SpaceX moved ORBCOMM to the larger Falcon 9s, but kept the price the same.
"That would be priced today at about $120 million," Eisenberg said.
SpaceX used Monday's launch to test a landing system it is developing to fly its rockets back to the launch site for refurbishment and reuse.
During Falcon 9's last flight in April, the first stage successfully restarted some of its engines as it careened toward the ocean, slowing its descent. The rocket also was able to deploy stabilizing landing legs before toppling over in the water. The booster, however, was destroyed by rough seas before it could be retrieved by recovery ships.
The rocket launched Monday suffered a similar fate. "Rocket booster re-entry, landing burn & leg deploy were good, but lost hull integrity right after splashdown (aka kaboom)," Musk wrote on Twitter.
Monday's launch was the 10th Falcon 9 rocket flight.
(Editing by Tom Brown)