Monday , July 26 2021

Iridium wants to complete the updated network with the launch of Falcon 9 on Friday – Spaceflight Now



Artistic concept of the Iridium Next satellites, which provide aircraft tracking coverage. Credit: Aireon

The launch of 10 more upgraded spacecraft aboard a SpaceX Falcon 9 rocket will complete the upgrade of Iridium's $ 3 billion global communications network, establishing the opening of new broadband and aircraft tracking services in the coming months.

With Friday's launch, SpaceX and Iridium have teamed up to launch 75 payloads on eight Falcon 9 flights since January 2017, giving Iridium a complete new spacecraft to replace and upgrade its old voice and data network.

The 229-foot Falcon 9 rocket, powered by a re-used first-stage booster that flew in September from Cape Canaveral, is scheduled to take off at 7:31:33 am (Brasília time). EST; 1531: 33 GMT) Friday at Vandenberg Air Force Base, California. The two-stage rocket will deploy the 10 satellites – built in partnership by Thales Alenia Space and Northrop Grumman Innovations Systems – one at a time for a period of 15 minutes approximately one hour after launch.

SpaceX plans to land the first stage of Falcon 9 again after Friday's launch on a sleep-wake ship that has positioned the Pacific Ocean a few hundred miles south of Vandenberg. It is expected that the payload rescue vessel from the launch company, Steven, will not try to get the shroud of Falcon 9 on Friday.

Matt Desch, chief executive of Iridium, told reporters before the launch that adding 10 more satellites to the grid – enough to complete the full constellation replacement – is "big business."

Iridium already has 65 new-generation "Iridium Next" satellites in orbit, and everyone is "happy and healthy," said Desch. The company's communications network operates on 66 active satellites scattered across six orbital planes, as well as spare parts, with inter-satellite radio links to transmit voice and data traffic without connecting through ground stations on Earth.

Iridium's first-generation "Block 1" satellites, built by Lockheed Martin, were launched from 1997 to 2002 and were designed for seven-year missions. Most of the fleet has survived this lifelong projection, and the new satellites have a dual mission as substitutes for the aging and outdated constellation of the 1990s, and as vehicles to introduce new services to expand beyond Iridium's landline and relay functions message.

The satellites scheduled for launch on Friday go to Airplane 3 of the Iridium fleet, and the takeoff is timed for the second with an instant launch window to precisely position the payloads in the correct orbit.

One of Iridium's new services, called Iridium Certus, will enable customers to transmit and receive higher-bandwidth messages, including high-definition video and Internet connections. Designed for ships, airplanes and other users on the go, Iridium Certus will provide Iridium customers with up to 1.4 megabits per second of L-band connectivity, up from 128 kilobits per second available in the previous generation of satellites.

Each Iridium Next satellite also hosts a radio receiver for Aireon, an Iridium affiliate established in partnership with air traffic control authorities in Europe and Canada. Aireon instrumentation will track air traffic around the world, including airplanes traveling outside the range of conventional ground-based radars.

The Iridium Next satellites were connected to their distributors inside a clean room at Vandenberg Air Force Base in California before they were mated to the Falcon 9 rocket. Credit: Iridium

"We started at Iridium in 2007 and started working in 2010. There was a lot of excitement when our first release finally happened two years ago on January 14, 2017, which was incredible and very important. But our final release … is by far the most important milestone of all. "Desch said.

"I'm sure you can imagine some of the reasons," he continued. "The completion of a $ 3 billion network upgrade, the new services we can launch as Iridium Certus broadband, IoT (Internet of Things) more efficient and Aireon, the financial transformation that will be allowed for Iridium. But for me, this release symbolizes something even more important. It means finally realizing the dream that the founders of this system had for more than 30 years. This means that our network will finally achieve the financial independence and security that makes a satellite network operator mature and successful, and creates many opportunities for us that we have never had before. This is a big deal for our customers, our partners and, frankly, for the industry itself. "

Originally backed by Motorola, Iridium pioneered the space and communications industries by putting the first fleet of commercial satellites of its size into orbit. But Iridium filed for bankruptcy shortly after launching its initial batch of satellites. A new company was formed to take over Iridium's assets, including satellites already in space, with a new business strategy, after high prices and weak demand condemned Iridium's original concept.

Iridium now has more than one million subscribers on its customer list, and the US Department of Defense is one of the company's key customers, along with aviation and maritime operators, land transport providers and users in the mining industry , forestry and oil and gas.

"What comes after Iridium Next? That answer is a lot, "Desch said. "The first new service we are about to present is our special L-Band Broadband service under the Iridium Certus brand. The name Certus is actually Latin, and means reliable, determined, secure and sure, all the adjectives we believe define Iridium and our new exclusive broadband service.

"We've gone through all the 2018 tests and put the Iridium Certus ready for the market, and the data tests are almost complete. In fact, they are complete for some of our service providers, who are already starting to provide the service to their marine customers before the official commercial launch. This official launch of the Iridium Certus is very imminent. "

Desch said the Iridium Certus offer will provide "life safety" broadband connectivity for crews and marine pilots. In a teleconference with reporters last week, he suggested that Iridium's new broadband service will not compete with high-performance geostationary satellites and planned "mega-constellations" of hundreds or thousands of ka-band and ku band, which target the individual consumer market.

"The Iridium Certus is applicable to the ever vertical industry, from maritime and aviation to the land mobile and the Internet of Things," said Desch. "We are focusing the service on life safety applications and other major specialized broadband applications. We believe that today is a $ 700 million market that we will be entering, mainly serviced by a satellite operator (Inmarsat), and we believe our service will be superior in every way. "

Internet of Things is an industry term for a type of network that transmits data, measurements and other signals among numerous objects around the world, from remote weather buoys to critical shipments traveling by road, sea or air.

"The Iridium Certus was not designed to compete with mega-constellations of high-performance satellites, or anyone using Ka, Ku or other bands," said Desch. "Iridium Certus is complementary. For example, in marine applications today, L-band terminals are often installed as a complement to the VSAT (Ku or Ka-band) terminals on board for coverage and safety purposes. "

In their favor, L-band communications typically require a ground receiver less than the Ku or Ka band, and the L-band is less susceptible to interference from rain, fog and thunderstorms, making it ideal for critical services. But the Ku- and Ka bands offer greater bandwidth than the L-band.

"In aviation applications, the Iridium Certus will be in the cockpit providing operational and security communications at optimal levels, while the Ka and Ku bands will be in the cockpit so everyone can use WiFi for entertainment services," said Desch .

The Falcon 9 rocket, ready to launch on SpaceX's eighth mission to Iridium, sits at the Space Launch Complex 4-East at Vandenberg Air Force Base in California. Credit: SpaceX

Like previous SpaceX launches for Iridium, the Falcon 9 rocket is slated to put the new satellites on Friday in a polar orbit about 625 kilometers from Earth.

Each of the 1,886-pound (1,886-pound) Iridium Next satellites will use its own propellers to climb 780 kilometers high, where six of the new spacecraft will meet the last of the satellites. old satellites in Block 1. The floor controllers at Iridium's network operations center in Leesburg, Virginia, will instantly switch traffic from the old satellite to the new, uninterrupted commercial service in a procedure the company calls " change of slots ".

The other four satellites launched on Friday are intended to be spare parts in Iridium's fleet.

"This will bring the total number of new Iridium satellites into orbit to 75, and after a full testing and validation process lasting several weeks, we will officially complete our new constellation," said Desch.

Iridium ordered 81 satellites Iridium Next from the Thales Alenia Space / Northrop Grumman team. Desch said that the remaining six satellites not yet released will remain in a ground-ready state and could be launched in the next few years to replenish the constellation.

Engineers are deactivating satellites that have been withdrawn from Iridium as new relay stations arrive in orbit. Most of the old satellites were maneuvered to fall back into Earth's atmosphere, and everyone will undergo a procedure known as "passivation," in which their batteries and propellant tanks are drained, rendering them inert and reducing the chance of an explosion. in the future.

Iridium blasts, a popular phenomenon for sky watchers over the past 20 years, will end when the last of the old satellites is retired. The Iridium satellites manufactured by Lockheed Martin have silver-plated Teflon antennas that behave like mirrors, reflecting the light from the sun to the Earth just before sunrise and soon after sunset.

Flares are predictable – for the second – and the satellite briefly becomes one of the brightest objects in the night sky. Heaven-watching applications and sites can provide the schedules of upcoming iridium flashes anywhere in the world.

The Iridium Next satellites, designed by Thales Alenia Space, have a different antenna format that does not produce flags.

"It's a sad time for the global community of observers," said Desch. "This is going to end."

Aireon prepares for air navigation tests in the North Atlantic

The aircraft tracking service managed by Aireon will also take a big step to start operations with Friday's launch.

Aireon says its service, which uses receivers from Harris Corp. to collect aircraft position data, will ensure that air traffic controllers know where planes are all over the world, reducing blind spots on busy transoceanic routes, improving safety and fuel efficiency.

Air traffic authorities in Canada, Ireland, Italy, Denmark and the United Kingdom are part of the Aireon joint venture with Iridium, and air traffic management organizations in Africa, the United States and other European countries are also preparing to use the system .

"With the complete Iridium Next constellation, Aireon will have real-time air traffic surveillance data comparable to terrestrial systems but for the entire planet, including the oceans and remote areas where it has never existed before," said Don Thoma , CEO of Aireon.

The Aireon system works by collecting position data transmitted by aircraft equipped with ADS-B technology. The Automatic Dependent Surveillance (ADS-B) technology allows an aircraft to determine its location through satellite navigation and then immediately transmits the position.

This reduces the reliance of air traffic controllers on old-fashioned tracking radars to track aircraft movements. But ADS-B receptors in the ground have the same limitations as radars – they do not allow uninterrupted tracking of airplanes over oceans and other remote regions.

When aircraft fly out of radar range, pilots are typically instructed to maintain a certain course and altitude, ensuring between 30 and 100 miles (about 50 to 150 kilometers) of separation between aircraft for safety purposes. With global real-time monitoring, these requirements can be relaxed.

The Aireon receivers on each of the Iridium Next satellites are designed to pick up the same ADS-B signals already transmitted by most aircraft. North American and European regulators have required all commercial passenger airplanes to be equipped with ADS-B technology by 2020.

"This was the main reason behind the creation of Aireon," said Thoma. "It has been clear for many years that a complete and truly comprehensive aircraft surveillance system is imperative, not only for the efficiency of air traffic management, but also for the safety of everyone who travels by plane.

"Aireon will support important safety improvements, including better understanding of controllers' status, reducing aircraft separation, and eliminating security breaches due to a lack of real-time surveillance," said Thoma. "This will reduce the controller's response time to normal situations, such as weather drifts or navigation errors by pilots, and of course, improve search and rescue response times.

"The use of Aireon will increase the efficiency of air traffic through optimized flight routes and better traffic flows. Real-time surveillance will allow airlines to plan and fly more direct routes, saving substantial amounts of fuel. "

According to Thoma, the Aireon system certification is expected to be completed by March, allowing operational testing using satellite-based ADS-B position data to begin in April in the North Atlantic for the busy air travel corridor between North America and Europe.

The Canadian and British air traffic authorities will oversee these tests, while the Federal Aviation Administration is reviewing similar operational tests in the Caribbean.

"The final release is very significant Aireon," said Thoma. "Delivery of the last 10 loads into orbit will finally complete the Aireon network, and once the Aireon loads are integrated into the constellation, our team of engineers and launch customers will complete a series of tests to provide final validation and certification of the system. system for operational use for air traffic control. "

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