Satellite Technology Feature Article
SpaceX Falcon 9 First Stage Engine Problem Throws off ORBCOMM OG2 Deployment
By Doug Mohney, Contributing Editor
Late on October 8, ORBCOMM (News - Alert) cleared up the mystery of why its OG2 prototype satellite isn't in the proper orbit. It also explained why it traces back to the first stage engine problem of the Falcon 9 rocket on its October 7 launch for a supply run to the space station.
The ORBCOMM OG2 prototype satellite was flying as a secondary payload on SpaceX's (News - Alert) Cargo Re-Supply Services (CRS-1) mission launched from Cape Canaveral, Florida on October 7, 2012 at 8:30 PM EST. One of the Falcon 9 rocket's first stage engines had a problem at about a minute plus into the launch, resulting in the problem engine shutting down and the flight computers adjusting burn time on the remaining engines to put its primary payload -- the Dragon spacecraft carrying cargo to the International Space Station (ISS) -- into the right orbit for a rendezvous.
Dragon successfully made it into orbit, but the Falcon 9 second stage did not make it into a pre-planned safety gate for its second burn to deliver OG2 into a planned transfer orbit of 350 by 750 kilometers. It instead, as first reported by Jonathan McDowell of Jonathan's Space Report, ended up in a lower 203 by 323 kilometer orbit. McDowell assumed correctly that the second stage didn't restart as planned to put OG2 into the orbit ORBCOMM wanted.
ORBCOMM and the Sierra Nevada Corporation engineers who built the satellite are now working out if and how far the current lower orbit can be raised to an operational one using the satellites on-board propulsion system. It isn't clear yet if they can salvage the satellite and get some useful work out of it at this point in time.
The OG2 satellite is a prototype/pathfinder for 18 new satellites ORBCOMM plans to launch in 2013 and 2014 as a refresh of its Machine-to-Machine (M2M) global communications network. OG-2 was/is to be used to evaluate performance for subsequent OG2 satellite launches and equipped with an Automatic Identification System (AIS) payload to receive and report transmissions from AIS-equipped vessels for ship tracking and other maritime navigational and safety efforts.
In mid-2013, ORBCOMM plans to launch an additional eight OG2 satellites on a SpaceX Falcon 9 and the remained of the 18 satellite constellation to be launched in 2014 on Falcon 9. Unlike today's launch, ORBCOMM's satellites will be the primary payload in the future flights.
Edited by Stefanie Mosca