I previously posted some of the innovations that I believe made Starlink possible. But possible and successful are not the same thing. For Starlink to be successful, they need to make dramatic progress on several fronts and the first is launch cadence.
To provide really solid coverage to the initial (quite large, if the registrations are to be believed) group of potential customers, Starlink needs to have about 4,000 satellites in orbit. Today they have just over 1,000 satellites in service. About 1,400 will give them pretty solid global coverage but without the redundancy needed to serve as many customers as are ready to sign up. That’s because each satellite can only serve so many users in a particular area. To serve more customers in a given area means more satellites.
SpaceX launches Starlink satellites in batches of 60 with its Falcon 9 rocket. They fly “flight proven” rocket boosters for all of their Starlink missions and they have a fleet of 7 of these already been flown boosters to work with. (SpaceX keeps the cost of Starlink launches down by taking a rocket that a commercial launch customer already paid for, and relaunching it with its own Starlink payloads.) It takes them a while to refurbish and stage these rockets between flights but with some improvements to that turnaround time and if they can maintain their existing fleet size, I do believe they can dramatically improve the pace of Starlink launches.
In 2020, SpaceX had 15 launches putting 900 satellites in orbit and ideally they’d almost double that pace, launching something like 1500 sats this year and for the next couple of years as well. They’ve said they intend to launch about every two weeks and so far this year they’re hitting that pace. They’ve had some delays because of weather, both at the launch site and the booster landing barges out at sea, but it hasn’t yet knocked them off their quickened pace.
They’ve also had repeated delays with a launch of booster B1049 which has flown 7 prior missions and may be starting to show its age. SpaceX wants to get at least 10 flights out of each rocket booster before retiring them but they may find that the current Block 5 design doesn’t consistently hit that mark. SpaceX cannot afford to launch Starlink missions on new boosters so maintaining their fleet of flight proven boosters is quite important.
A further concern is the fate of booster B1059 which failed to land (crashed into the ocean) earlier this month, reportedly because of heat damage. B1059 had only flown 5 prior missions so hopefully it wasn’t wear and tear but some other issue that SpaceX can mitigate for the rest of the fleet if needed. As noted above, they can’t afford to lose too many of their flight proven boosters without it putting a real dent in their launch cadence.
In addition to an improved Falcon 9 launch cadence, SpaceX needs to make dramatic progress on its next generation rocket, named Starship. Where Falcon 9 is about 12 feet in diameter and 230 feet tall with a launch to low earth orbit capacity of about 50,000 lbs, Starship will be 30 feet in diameter and 400 feet tall with the ability to put 220,000 lbs into low earth orbit.
If all goes well with Starship, SpaceX should be able to carry about 400 satellites to orbit in one launch (compared to the 60 that Falcon 9 can hold.) Starship is also being designed to be rapidly and fully reusable so we could see amazing growth in the size of the Starlink constellation starting in two to three years when Starship should be ready to take over the Starlink missions from Falcon 9.