UPDATED 6/23/14 AT 5:00 P.M. EDT – SpaceX needs additional time to assess a potential issue that was identified during pre-flight checkouts during Sunday’s Falcon-9 OG2 launch attempt. Will stand down until at least the first week of July, Range proceeding with previously scheduled maintenance. Launch date will be determined when Range confirms next available launch opportunity.
Following two back-to-back launch delays, frustrated on Friday evening by an issue with the Falcon 9 v1.1 rocket and on Saturday evening by dynamic weather in the Cape Canaveral area, it was hoped that the third attempt tonight (Sunday, 22 June) might be the charm for SpaceX in their troubled effort to get six Orbcomm Generation-2 (OG-2) satellites into low-Earth orbit. Earlier today, Orbcomm, Inc., announced that it was targeting a liftoff from Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station, Fla., at 5:30 p.m. EDT, right at the start of a spacious three-hour “window.” However, for the third time in as many days, the situation did not appear to be on SpaceX’s side, and a little after 2:30 p.m. the 45th Space Wing tweeted that the launch had been scrubbed. An AmericaSpace enquiry to SpaceX for an update produced a response that another launch attempt would occur Tuesday, 24 June (later delayed again to NET July).
If the weather at the Cape has proven particularly dynamic in recent days, then the dynamism of events surrounding this mission has been nothing less. Friday’s down-to-the-wire launch attempt saw a decision to move T-0 until the very end of the 53-minute window, in order to allow SpaceX engineers to tackle an anomalous “pressure decrease” in the second stage of the Falcon 9 v1.1. This ultimately proved impossible in the ever-dwindling available time and a 24-hour postponement was called. Yesterday, the weather appeared to be the overriding concern. Initial hopes that conditions might clear prompted mission managers to again recycle the clock to track a revised T-0 at the end of the window, but shortly before the countdown was due to reach T-13 minutes—the point at which all stations are polled for their “Go/No-Go” status, ahead of the “Terminal Countdown”—it was concluded that the teams could not get comfortable with the weather situation and the second launch attempt was called off.
“Rescheduled information will be made once it becomes available,” read a tweet from the 45th Space Wing last night. It was one of the few available information sources for this second attempt, for SpaceX—the Hawthorne, Calif.-based launch services organization, headed by PayPal and Tesla Motors entrepreneur Elon Musk—had earlier announced that it would not be providing a live webcast. This provoked an immediate negative response on Twitter from many individuals and media outlets, some of whom harshly criticized SpaceX for failing to conduct its business in an open manner. Their efforts to implore Musk to reconsider seemingly bore fruit, for it was announced on Sunday afternoon that the third attempt would be webcasted. “SpaceX is planning to live webcast the Orbcomm OG-2 launch here, starting at 2:16 p.m. PDT/5:16 p.m. EDT,” it was explained.
The company’s decision for not webcasting Saturday night’s launch attempt remains unclear. Spokesperson Emily Shanklin, responding to a Spaceflight Now question, highlighted “no special reason” for the absence of coverage. She added that such webcasts require “a lot of resources” and—ironically, in view of the fact that the OG-2 launch is only SpaceX’s third mission of 2014—that “these launches are becoming more routine and the full webcast isn’t really appropriate anymore.”
In spite of a predicted deteriorating weather situation on Sunday, it was decided to press on with a third launch attempt. According to U.S. Air Force meteorologists from the 45th Space Wing, the “abundance of moisture, warm temperatures and south-westerly flow” from a subtropical ridge to the south of Cape Canaveral would cause the sea breeze to develop and form showers and thunderstorms. “Conditions will gradually improve near sunset and through the evening hours,” the 45th noted in its weather summary for Sunday. “The primary concerns are cumulus clouds, lightning, anvil clouds and high electric fields within the window. With conditions not appearing to change through mid-week, similar weather conditions will persist for a few days.” In summary, it was revealed that there existed only a 20-percent likelihood that the situation would be optimum for the Falcon 9 v1.1 to fly.
At length, with three hours to go before the opening of Sunday’s window, the call to scrub the launch attempt was made. Responding to an AmericaSpace request for information, SpaceX replied: “Today’s Orbcomm launch attempt has been scrubbed to address a potential concern identified during pre-flight checks. The vehicle and payload are in good condition and engineering teams will take the extra time to ensure the highest possible levels of mission assurance prior to flight. The rocket will remain vertical on the launch pad, with the next available launch opportunity targeting Tuesday, 24 June.”
Originally scheduled to fly in May, this mission has been repeatedly postponed, due to problems with the Falcon 9 v1.1 and, more recently, with one of the six OG-2 satellites. When they do eventually make it into space, the satellites will enter a circular orbit of 460 x 460 miles (750 x 750 km), inclined 52 degrees to the equator. They will remain in service for at least five years and provide two-way messaging services for global customers.
Following a failed inaugural OG-2 launch in October 2012, the satellites were all built by Sierra Nevada Corp. (SNC). Another 11 satellites—which are currently undergoing final processing at SNC—are expected to fly aboard another Falcon 9 v1.1 later this year. Orbcomm announced in May 2008 that SNC would build a total of 18 satellites for a fee of $117 million, with an option for up to 30 others. A few weeks later, Orbcomm chose Argon ST, a subsidiary of Boeing, to develop advanced communications payloads to increase subscriber capacity by up to 12 times over earlier satellites, as well as transmitting data at higher speeds and quantities. Designed with Automatic Identification System (AIS), it is expected that the OG-2 network will be marketed by Orbcomm to U.S. and international coast guards and government agencies, as well as private security and logistics companies.
At the time of writing, 45 Orbcomm satellites have been delivered into orbit since July 1991, aboard a wide range of vehicles, including Europe’s Ariane 4, the air-launched Pegasus booster, Orbital Sciences Corp.’s Taurus, China’s Long March 4B, India’s Polar Satellite Launch Vehicle (PSLV), and Russia’s Cosmos-3M. Initial “Concept Demonstration Satellites” led to the OG-1 network and a replenishment series of “Quick Launch” missions, with the OG-2 series intended to supplement and eventually replace the first generation. “Due to their high efficiency and modular design, these satellites have substantially more capacity to service a larger number of subscribers, thus making the network more efficient with few satellites than the OG-1 satellites that are currently in orbit,” explained Pat Remias, SNC’s Space Systems senior director of programs. “SNC has established a satellite production line in our Louisville facility to integrate and test each vehicle rapidly, with up to six satellites processing simultaneously.”
By 2009, Orbcomm had settled on SpaceX’s Falcon 9 as its vehicle of choice, with the inaugural launches originally anticipated the following year, but postponed several times due to delays and schedule slips. The first OG-2 “prototype” satellite was launched in October 2012, flying “piggyback” alongside SpaceX’s CRS-1 Dragon. However, an upper stage engine shortfall caused it to be inserted into a low orbit of just 125 x 200 miles (200 x 320 km), instead of the planned 220 x 470 miles (350 x 750 km). Despite the successful deployment of the satellite from the final stage of the Falcon 9, it quickly became clear that the low orbit was “unworkable” and the first OG-2 re-entered the atmosphere to destruction a few days later.
In preparation for the next batch of OG-2 launches, four satellites arrived at Cape Canaveral Air Force Station from SNC shortly after noon EDT on 21 April 2014, followed by two others on the 26th. Each satellite weighs 380 pounds (172 kg) and, when fully deployed in orbit, will measure 42.7 feet (13 meters) x 3.3 feet (1 meter) x 1.6 feet (0.5 meters) and generate about 400 watts of electrical power. The satellites underwent extensive checks and fueling of their hydrazine attitude-control systems, and on 6 May SpaceX performed a Flight Readiness Review and confirmed its status as “Go” for launch on the 10th. The payload stack, containing the six satellites on their Expendable Launch Vehicle Secondary Payload Adaptor (ESPA) “ring,” was subsequently encapsulated within the bulbous Falcon 9 v1.1 fairing and attached to the rocket.
Rollout to SLC-40 occurred early Thursday, 8 May, after which SpaceX intended to conduct a standard static “hot-fire” test of the nine Merlin-1D first-stage engines. However, a considerable helium leak on the first stage caused the hot fire to be postponed by 24 hours, then scrubbed indefinitely. “Today’s attempt to perform the static firing test was stopped while the rocket was being fueled,” explained Orbcomm on the 9th. “Both the OG-2 satellites and the rocket are in safe condition and will be rotated horizontal and rolled back into the integration facility. This will prevent us from launching this weekend.” Hardware from the first stage was removed and returned to SpaceX’s facility in Hawthorne, Calif., for inspections and verifications to ensure that the problem did not represent a systemic failure and a threat to future missions.
On 19 May, a revised target of 11 June was announced and it was noted that the Orbcomm and SNC processing teams would arrive at the Cape about a week before launch to participate in the lengthy process of re-encapsulating the OG-2 satellites back into their adaptor. By the end of May, the launch had moved a further 24 hours to the right and on 10 June Orbcomm revealed a new target of No Earlier Than the 15th. “During final integration on one of the OG-2 spacecraft,” it was explained, “we encountered a minor issue resulting in a few extra days of delay to perform precautionary steps to ensure there are no operational concerns with the satellite.” In the meantime, last Friday, SpaceX performed a successful static hot-fire test, but it was feared that upcoming maintenance of Eastern Range tracking assets might result in a further delay until July. However, after “finalizing the launch schedule with the Range at the Cape”—a new date of 20 June was issued. Both it and two subsequent attempts on Saturday and Sunday were frustrated by a mix of weather and technical issues.Missions » Commercial Space » ORBCOMM » SpaceX OG2 M1 »