Fairings might only be reused on Starlink missions until Mr. Steven catches one
SpaceX’s fairing recovery efforts are gearing up again after a 3-month-long slow period caused by Mr. Steven suffering damage in late February that have prevented SpaceX from attempting to catch fairings since then. Luckily, Mr. Steven has now been fixed and should be ready in time to try to catch a fairing in about a month during the STP-2 launch. In the meantime, SpaceX has been recovering fairing halves by landing them in the ocean and hoisting them up on board two ships. The company plans on reusing them even though they came into contact with sea water and I have a theory that until Mr. Steven manages to catch a fairing, we’ll only see reused fairings on Starlink missions.
First, let’s quickly recap what’s been going on with fairing recovery in the last few months. As for Mr. Steven, the ship first attempted to catch a fairing in February 2018 and since then made 4 more attempts, none of them successful. SpaceX also conducted several fairing drops last year for practice. Then, almost exactly a year after its debut, Mr. Steven was damaged in February 2019 while it was on its way to the fairing landing area during the Nusantara Satu mission. It’s still unclear what exactly happened that day but the ship returned to port damaged, with her net and two of her metal arms missing. The two remaining arms were then removed also. It was obvious Mr. Steven won’t be catching fairings anytime soon.
A few weeks later, SpaceX recovered both fairing halves during the Arabsat 6A mission by fishing them out of the ocean. Elon Musk then announced that those fairing would be reused on a future Starlink mission. With no apparent activity around Mr. Steven since the accident, this led many people to speculate that SpaceX is giving up on trying to land the fairings in a net. I’ve argued that, while recently introduced fairing upgrades might have made it easier to reuse fairings that landed in water, we’d see Mr. Steven in action again because it would still be preferable for SpaceX to keep the fairings dry when recovering them. The fact that SpaceX isn’t giving up on Mr. Steven yet was confirmed in recent days when the ship finally received new arms and a net. That means that it should be ready in time for the STP-2 mission which represents the next opportunity to try and catch a fairing.
During the Starlink-1 mission on May 24, both fairing halves were also recovered from the water by SpaceX ships GO Searcher and GO Navigator. Interestingly, photos shared by Elon Musk showed that SpaceX didn’t equip the fairings with acoustic tiles (compare the two photos below). These tiles normally line the inner side of the fairing to protect sensitive satellites from vibration and acoustic effects.
There are several possible reasons why SpaceX would choose to not use the tiles for Starlink launches:
- It reduces total mass which the rocket has to accelerate (that saves fuel and allows more satellites to be launched)
- It frees up more space inside the fairing (more satellites will fit in)
- It reduces costs and saves time (buying or making the tiles and then installing them in the fairings costs time and money)
Another reason has to do with the fairing’s recovery and reuse. If the main problem preventing SpaceX to routinely reuse fairings that landed in the ocean is the sea water contamination of the tiles, you can just remove the tiles if you don’t need them on the next mission. This might explain why both times Elon Musk talked about reusing fished out fairings (during missions SSO-A and Arabsat 6A), he said they’d be reused on “an internal mission” or a Starlink launch.
If it’s impractical to fully refurbish fairings, tiles and all, after they land in the ocean, it’s possible that we might not see a fairing reuse on a non-Starlink mission until Mr. Steven manages to catch a fairing. In that scenario, the entire fairing, including the acoustic tiles, stays dry and can presumably be reused very easily. Until then, SpaceX might only be able to reuse fairings for Starlink missions because they can just remove the contaminated tiles that would have otherwise pose a risk to sensitive payloads for other customers.
SpaceX hasn’t actually reused any fairings yet, so we’ll have to wait and see. We might not need to wait long, though. Elon Musk said the Arabsat 6A fairings would be reused on a Starlink mission later this year and we know that SpaceX plans up to 6 more of those in 2019.
Tip: To learn much more about Mr. Steven and SpaceX’s fairing recovery efforts, read our Fairing Recovery Compendium article.