A Closer Look At The Catch Of Super Heavy

Yesterday we watched the return and catch of the Super Heavy booster on Starship’s fifth flight. Between then and now we have received a handful of new information from both SpaceX and Musk regarding the condition of the booster, the purpose of the catch, and when to expect Flight 6.

Based on what they said, it seems that there were only some minor issues that they expect to fix before the next Starship flight.

Booster’s Condition

When looking at footage of the landing some of the only visible damage included some metal pieces flying off not long after the landing burn along with a small fire following the catch. Not long after this fire went out and SpaceX eventually lowered the chopsticks and placed the booster on the launch mount.

Specifically, last night Elon Musk tweeted saying, “Just inspected the Starship booster, which the arms have now placed back in its launch mount. Looks great! A few outer engine nozzles are warped from heating & some other minor issues, but these are easily addressed. Starship is designed to achieve reflight of its rocket booster ultimately within an hour after liftoff. The booster returns within ~5 minutes, so the remaining time is reloading propellant and placing a ship on top of the booster” he said.

This included an image of the booster on the Orbital Launch Mount which they even ended up connecting the quick disconnect to as well.

However, focusing on these comments, it seems the main addressable damage is some warping to the engine nozzles. As the booster was returning you could see the buildup of heat as it sped through the atmosphere. This reentry heating likely had an effect and began much sooner during the booster’s descent than the footage highlights. It’s possible this combined with engine ignition followed soon after for the landing burn and even the initial launch put extra stress on the nozzles.

That being said he mentioned that they are easily addressable and with that, should be fixed by the time we see Flight 6.

Over the last 24 hours, we also got quite a bit more footage including close-ups of the landing from the tower. Thanks to two different angles we can see the booster lowering right as the arms come in and work to position themselves right under the two pins. What’s interesting is that they also aren’t moving in unison but instead, both making somewhat unique adjustments based on the booster’s location while it’s falling. In addition, they provided a great image close-up of one of the catch-point pins held up by the Mechazilla arms. This helps put in perspective the accuracy and small margin of error when catching a Super Heavy booster. It also highlights that the orientation of the booster matters as there are only two catch points, one on either side.

After the catch, many people were wondering why SpaceX caught the booster in the first place and what benefits it provides over landing similar to the Falcon 9. Earlier this morning Musk responded, “The strong gravity of Earth makes the physics of a fully reusable rocket with positive payload margin extremely difficult to solve, which is why it has never been done before. Removing the mass of landing legs from the booster and ship by making the tower do the work of final velocity attenuation greatly improves payload margin. This architecture also simultaneously substantially increases launch cadence, because the same arms that lift the booster and ship onto the launch stand also catch them, allowing immediate placement of the booster back on the launch stand and the ship back on top of the booster” he said.

In other words, you don’t need landing legs which saves weight, and catching the booster at the launch site facilitates a rapid turnaround. In the future SpaceX wants to catch a booster and have it launching again in about an hour. Having it caught at the launch site could help support that ambitious timeline.

Also, something a lot of people didn’t notice is that SpaceX actually activated the water deluge system during the catch attempt. From most angles, it’s hard to see but after the engines are cut off you can clearly see the water still coming out of the steel plate. They likely did this as a might as well even though the pad can definitely hold up to three Raptor engines, especially that high up.

Flight 6

With Flight 5 now complete, SpaceX will begin working toward Flight 6 which some expect to occur not too long from now. Hardware is already in great shape with Ship static fires for the next flight occurring back in September.

The main factor will have to do with the upcoming flight profile. If SpaceX makes some significant changes then a launch much later this year or early next year would be likely. However, if they have a very similar flight profile or include minimal changes, some believe we could see Flight 6 as soon as November or December of this year. Obviously, we won’t know more until the coming weeks but the results of Flight 5 are definitely beneficial.

After the launch, SpaceX released an official statement and highlighted what was accomplished. Here they were quoted saying, “Starship’s fifth flight test lifted off on October 13, 2024, with our most ambitious test objectives yet as we work to demonstrate techniques fundamental to Starship and Super Heavy’s fully and rapidly reusable design. And on our first try, Mechazilla caught the booster.”

“Following a successful liftoff, ascent, stage separation, boostback burn, and coast, the Super Heavy booster performed its landing burn and was caught by the chopstick arms of the launch and catch tower at Starbase. Thousands of distinct vehicle and pad criteria had to be met prior to the catch attempt, and thanks to the tireless work of SpaceX engineers, we succeeded with catch on our first attempt.”

“Prior to catch, Starship executed another successful hot-staging separation, igniting its six Raptor engines and completing ascent into outer space. It coasted along its planned trajectory to the other side of the planet before executing a controlled reentry, passing through the phases of peak heating and maximum aerodynamic pressure, before executing a flip, landing burn, and splashdown at its target area in the Indian Ocean. The flight test concluded at splashdown 1 hour, 5 minutes and 40 seconds after launch.”

They then mentioned, “The entire SpaceX team should take pride in the engineering feat they just accomplished. The world witnessed what the future will look like when Starship starts carrying crew and cargo to destinations on Earth, the Moon, Mars and beyond. Congratulations to the SpaceX team for taking this leap in our quest to make life multiplanetary. And thank you to our customers, Cameron County, spaceflight fans, and the wider community for the continued support and encouragement” they said.

It’s clear SpaceX is extremely happy with the result of this flight and excited to move on to the next launch. Before flight 5, one of the key upgrades made to Starship was a complete rework of its heatshield, with SpaceX highlighting that technicians spent more than 12,000 hours replacing the entire thermal protection system with newer-generation tiles, a backup ablative layer, and additional protections between the flap structures. Before the launch they said, “This massive effort, along with updates to the ship’s operations and software for reentry and landing burn, will look to improve upon the previous flight and bring Starship to a soft splashdown at the target area in the Indian Ocean.”

Based on what we saw, the heat shield definitely was improved. There were moments of burn-through in addition to some tiles breaking off but the Ship managed to survive reentry in much better condition than on Flight 4. When it comes to the ablative material, SpaceX made it clear that this is not the best for reusability, but it acts as somewhat of a safeguard in the event that tiles are compromised. With all that in mind, we can still expect SpaceX to continue innovating and working on the Thermal Protection System.

When talking about the ablative material Musk said, “It’s not good for reuse but it’s good for saving your butt if a tile cracks or falls off. It’s very tricky to put these tiles and have them work well because the tiles are ceramics, they are like a coffee cup or a dinner plate. So you have a whole bunch of dinner plates on a rocket that is shaking. It’s shrinking cryogenically with the propellant and then expanding under pressure and then the tiles are expanding when they get hot. So there’s a lot of expansion and contraction happening while trying to keep all these brittle tiles from cracking or breaking off” he said.

Everything considered, Flight 5 was by far the most impressive launch and had a few important milestones that were met. Over the next few weeks, we can expect Starbase to be busy as they prepare for Flight 6 and gather as much information as possible from Flight 5. This not only includes the booster catch-related data but also the reentry of the upper stage and its eventual splashdown. Something to look forward to in the near future.

Conclusion

On the first attempt, SpaceX managed to catch the Super Heavy booster out of the air. With the exception of some nozzle warping from excessive heat, it’s reported that just about everything else worked nearly perfectly. SpaceX will begin working to fix this issue and move on to new hardware for the next launch.





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