The Making of an Intelsat Satellite

Intelsat’s newest communications satellite, Galaxy 30 (G-30), went into service yesterday. It’s now providing Intelsat customers in North America with high-performance television-distribution service.

In 2020, Intelsat announced our plans to procure, build and launch seven C-band satellites over the next few years. And earlier this year, we announced a contract for two software-defined satellites that are scheduled to launch in 2023.

Did you know that as the world’s preeminent satellite communications provider, Intelsat has launched more satellites than any other provider over our 50-plus years of service? Since Intelsat 1 (“Early Bird”) in April 1965, Intelsat has launched over 150 satellites. 

The process of expanding and refreshing our satellite fleet (the world’s largest and most powerful) involves more than just surfing the internet for the best deal, or picking the latest and greatest satellite out of a catalog.

A lot of work goes into bringing a new satellite to life, and in this blog post, we’re giving you a sneak peek into the process.   

What Does it Take to be an “Intelsat Satellite?”

Our satellites are built to extremely detailed specifications that are set by our highly skilled engineering teams. They don’t create these specifications from scratch, however – they work closely with our commercial teams, and directly with our customers, to fully understand our customers’ communications and connectivity needs.     

The engineering team then consolidates those requirements into a technical document that is socialized with potential satellite manufacturers, who are typically given a month or two to answer our request for a formal manufacturing proposal. Manufacturers respond back to us with details on everything from the technical capabilities of a satellite to the proposed delivery schedule.

The Intelsat engineering team then carefully evaluates all proposals, ranking them on their merits and finally making a recommendation. Once approved, the work to negotiate a contract with the preferred bidder begins, and could take up to a few months, depending on the complexity of the new satellite.

Construction Begins

During the entirety of the construction phase, Intelsat has a team of engineers co-located at the manufacturer’s site to ensure the satellite is built and tested to our specific requirements and delivered on the agreed-upon schedule.

The first phase of construction involves subassemblies, which are built using components that are either developed in-house or supplied by subcontractors. Every single component that is installed on a new satellite – even in a subassembly – undergoes a series of tests to verify that it will provide the expected performance when it’s in space. There are several hundreds of units (“boxes”) which are themselves made of several hundreds of components (“parts”). Those units are linked together by miles of electrical harness and Radio Frequency (RF) waveguides or coaxial cables.

Once all of these subassemblies are built, they are then put together to create “the satellite” or what we sometimes call “the system.” 

Test 1 – Thermal Vacuum

The assembled satellite then undergoes another series of tests to verify that it will provide the performance we expect.

Those “system-level” tests include a “thermal vacuum test” where the satellite is installed inside a large chamber where the air is “sucked” out to produce the vacuum conditions that the satellite will see in space. This test is extremely important as the heat transfer inside the satellite from one zone to another cannot be simulated in a normal ambient condition (“under air”).

Test 2 – Vibration

The satellite is then mounted on a “shaker table” and is “shaken” to reproduce the large vibrations that the satellite will see during the roughly 30-minute-long launch phase.

A large, white blanket is set up beneath the satellite to catch any elements that might fall during this testing. Sometimes it catches small parts, such as tie wraps or even bolts and screws. If that’s the case, the team has to explain where those “fallen parts” are coming from. Keep in mind, a satellite is made of hundred thousands of different parts and components.

Test 3 – Acoustic  

During the launch phase, the satellite is not only “shaken,” it is also exposed to very high noise levels. An acoustic test ensures the satellite will not be damaged if the noise becomes too great.

The satellite is placed into an acoustic chamber with large speakers that can produce a loud sound. The speakers used are not that different than the ones used in rock concerts and can emit eardrum-splitting volumes.

Test 4 – RF Tests

After the completion of those mechanical tests, the satellite undergoes Radio Frequency (RF) tests. This happens in an “anechoic” chamber, which is essentially free from RF interference. There, the satellite can be tested for any emissions that might interfere with its operation.

Ready to Ship

Once the satellite is built, it will be placed into a shipping container and airlifted to the launch base. There is only one commercially available plane that is big enough to carry the satellite container, the Antonov-124.

Reporting for Duty

At the launch site, the satellite undergoes another series of ground tests to verify that it was not damaged during shipment.

The launch site is also where the satellite is fueled. This is a very hazardous operation that requires special protective equipment for the propulsion crew. It is very important that the propellant remains “pure” as any contamination could prevent the satellite thrusters from working efficiently in orbit.

Once fueled, the satellite is “encapsulated,” meaning it is placed inside the fairing (“nose”) of a launch vehicle and almost ready for launch.

Preparing for Launch

Launch days are full of additional preparations. A launch can only occur during a certain window of time, the daily “launch window.” This launch window varies from launch to launch and is defined by the satellite’s need for a given position of the sun with respect to orbit – that sun position is directly tied to the liftoff time. Inclement weather, such as high winds, lightning and freezing temperatures can all delay a launch.

Launch windows for commercial satellites are typically between one and two hours long. The longer the launch window, the greater the chance that liftoff can occur on a given day because it gives the team more time to wait for better weather or correct a technical issue. If this launch cannot take place during the launch window, it’s likely that another attempt wouldn’t be possible until the following day.

Once a satellite’s launch vehicle finally takes off, it usually takes around 30 minutes for the satellite to separate from the launch vehicles, after which it’s on its trajectory to space.

Where Does a Satellite Live?

Intelsat’s satellite fleet is currently composed of geostationary satellites, and their locations in space are defined by their orbital longitude (85˚E or 133˚W for example).

No operator can put a new satellite wherever they would like. Rather, satellite operators need to be granted “rights” to operate a satellite at a given longitude in a particular frequency (C-, Ku- or Ka-band). Those rights are referred to as orbital slots and managed by the Federal Communications Commission (FCC) in the U.S. and the International Telecommunications Union (ITU) internationally. 

Going the Distance

A team of engineers from Intelsat and the satellite manufacturer are in charge of performing all operations to raise the satellite orbit to its designated geostationary altitude before it goes into service.

Through a series of maneuvers, the satellite will go from 150 miles to over 22,400 miles over the earth, using about 2/3 of it propellant in the process. The remaining third will last for the duration of the satellite’s 15 or so years of useful life. This phase, called “Orbit Raising” usually lasts two to three weeks, but can extend to six months for satellites that use electric propulsion.

Fit for Service

Once in its designated orbital slot, the satellite will undergo a final series of tests to verify that it wasn’t damaged during launch and is ready for service. This phase can last one to two months, depending on the complexity of the satellite.

Of course, entering into service is just the beginning for a satellite. For the next 15-plus years, a dedicated team of Intelsat engineers will manage the satellite, making sure it stays in its orbital slot and delivers the communications and connectivity services our customers expect.

Interested in learning more about satellites? Check out our Satellites 101 primer.