PARIS — An outside assessment has concluded that the current 66-satellite Iridium constellation will remain operational until 2017 and that the mobile satellite service would remain viable even if the fleet was reduced to 36 satellites, Iridium Communications officials said Dec. 16.
Iridium officials said the analysis, conducted on behalf of the institutions financing the company’s second-generation constellation, called Iridium Next, stress-tested key components of the satellite design on the ground by subjecting them to bursts of radiation to simulate what the satellites encounter in orbit.
The analysis was overseen by the Aerospace Corp. of El Segundo, Calif., a nonprofit, U.S. Air Force-sponsored aerospace analysis center, at the request of the bank consortium and the French export-credit agency, Coface, Iridium officials told investors in a day-long series of briefings. Coface is guaranteeing a $1.8 billion package to finance Iridium Next.
The findings, which were delivered in October, conclude: “There are no electrical or mechanical issues until 2017, and we begin launching Iridium Next in 2015,” said S. Scott Smith, Iridium’s executive vice president for Iridium Next.
The Coface-backed package is part of an estimated $3 billion that Iridium is spending on Iridium Next, which like the current constellation will feature 66 operational satellites, plus six in-orbit spares and nine spares that will remain on the ground to be used in the event of a launch failure.
The satellites, each weighing 850 kilograms, are scheduled to be launched, nine at a time, aboard Falcon 9 rockets built by Space Exploration Technologies Corp. (SpaceX) of Hawthorne, Calif.
Iridium’s plan to finance Iridium Next and repay the bank loans hinges heavily on the company’s ability to continue to generate cash from the current satellites. Smith said on-board fuel has never been an issue as the satellites, built by Lockheed Martin and Motorola, carry more than 114 kilograms of fuel each, which is more than what they need to maintain themselves on station.
But Smith said radiation, which is suspected of crippling the satellites operated by Iridium competitor Globalstar Inc. of Milpitas, Calif., is a legitimate concern for Iridium.
To secure the bank financing, Smith said Iridium agreed to a Coface-ordered due-diligence assessment of the likelihood that Iridium would be able to maintain a functioning service until the arrival of Iridium Next.
Iridium took radiation-sensitive parts from spare first-generation Iridium satellites that have remained on the ground, and these components were bombarded with gamma rays last summer. Smith said the tests concluded that the satellites were 80 percent more resistant to radiation than even Iridium had dared hope. “Because of that, radiation is not an issue.”
A third danger for Iridium satellites is the threat of an in-orbit collision with even a small piece of the space debris circling in low Earth orbit. A dead Russian satellite collided with an Iridium spacecraft in February 2009, and industry experts agree that the growing population of debris below 2,000 kilometers in altitude poses a risk to satellites as well as to astronauts.
Smith said that after the collision, the U.S. Defense Department’s Joint Space Operations Center (JSPOC) changed its policy on notifying commercial satellite operators of debris threats. Before the collision, defense authorities monitoring the U.S. Space Surveillance Network of ground-based radars would notify commercial operators only of a risk from a large piece of debris.
Since the February 2009 event, Smith said, JSPOC has written an operating protocol under which an operator like Iridium is informed when even a small piece of tracked debris is identified as a threat to a commercial satellite.
Informed that a piece of debris may be on a collision course, Iridium plots an avoidance maneuver and submits it to JSPOC, which then integrates the data into its program to determine whether the move will not only avoid the debris in question but also not create new collision threats. The agency returns its analysis to Iridium, which then executes the maneuver.
“Now, once every couple of weeks we do a maneuver,” Smith said.
The same due-diligence assessment concluded that even if, for whatever reason, Iridium’s current satellites start to fail, the service would remain “viable” with just 36 operational spacecraft, Smith said. He did not provide a definition of system viability. Globalstar has maintained a partial voice service and diversified into one-way data services despite its satellites’ failing health but has taken a major financial hit as it waits for its second-generation constellation to be launched.
Iridium continues to hunt for customers, most likely government agencies, to pay to place small payloads on an area of the Iridium Next satellites that has been specially set aside for that purpose.
Don Thoma, Iridium executive vice president for marketing, told the conference the company is still counting on between $200 million and $300 million in cash from hosted-payload customers before the Iridium satellites are launched between 2015 and 2017. These customers then would pay an annual fee for operations.
Thoma said multiple hosted-payload possibilities are being explored with the U.S. government, both civil and military agencies, for space situational awareness, air traffic control, weather forecasting and other services.
Set aside on each Iridium satellite is a place for an instrument weighing up to 50 kilograms, measuring no more than 30 by 40 by 70 centimeters and requiring no more than 50 watts of power on average, with peak demand of 200 watts. Iridium would reserve a data downlink capability of 100 kilobits per second, on average.
Iridium is expecting that its earnings before interest, taxes, depreciation and amortization for 2010 will be around $157.5 million, and that it will rise by 17.5 percent in 2011. Subscriber count will grow by 20 percent in 2011 as new machine-to-machine and push-to-talk phone services for troops grow quickly even as conventional land-based telephone service growth slows.
In addition to a resurgent Globalstar with a new satellite constellation, Iridium competes with Thuraya of the United Arab Emirates and with London-based Inmarsat. Inmarsat has recently introduced a low-cost satellite telephone to woo Iridium customers, and Iridium is responding by introducing a stripped-down version of its current phone, Thoma said.