Starship Flight 5 The Catch

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SpaceX is set to launch the fifth flight of Starship, with another new milestone added to the objectives. Booster 12 and Ship 30 are tasked with lift-off from Pad A at Starbase, with the former also set to attempt a landing at the launch tower, caught by Mechazilla’s Chopstick arms. SpaceX controllers will make the call during the booster’s return.

The launch is scheduled for an opening of the window at 7 am Central Time on Sunday morning, following approval being granted by the FAA.

How to watch the flight:

NSF Starbase Live – 24/7
NSF Flight 5 Stakeout Stream – from 6 pm Central
NSF Flight 5 LIVE – YT – from 4 am Central
NSF Flight 5 LIVE – X – from 4 am Central

Flights 1-4

So far, SpaceX has made tremendous strides from flight to flight in the Starship Program. Flight 1 was all about getting off the pad and getting data on booster performance. Even though the stack only got to 40 km, SpaceX achieved at least clearing the tower and getting booster data.

Flight 1 paved the way for Flight 2 to make it to stage separation using a new method for Starship,  hot staging, and almost got the Ship to engine cutoff. However, Booster 9 was lost during boost back, and Ship 25 was lost near the end of its burn.

Starship Flight 1 B7/S24 (Credit: Max Evans for NSF)

Taking the lessons learned from Flight 2, Flight 3 was a huge step forward. Booster 10 made it past the boostback burn but was lost during the landing burn. Ship 28 made it into space but lost roll control during the coast phase and started to tumble. This resulted in the heat shield not facing the atmosphere constantly, and Ship 28 burned up on reentry.

Then came Flight 4, which saw our first engine out on the accent with the booster since Flight 1. However, Booster 11 completed its boostback burn and its landing burn before tipping over and exploding. According to SpaceX Vice President for Build and Flight Reliability Bill Gerstenmaier, when referring to Booster 11’s landing accuracy, “We landed with half a centimeter accuracy in the ocean.”

A then-live view of Ship 29 during atmospheric reentry, provided by SpaceX’s Starlink constellation. Credit: SpaceX on X

During the Ccoast phase, Ship 29 didn’t do any of the extra testing that Ship 28 did and just coasted into reentry. With a perfect attitude and full control, Ship 29 reentered. During reentry, plasma got into the port-side forward flap hinge, nearly melting it off. However, Ship 29 maintained control and completed a flip-and-burn with a soft splashdown in the Indian Ocean.

These achievements and milestones now prepare the Starship program for its biggest test yet: catching the booster.

Timeline and Trajectory

Flight 5 is slated to be relatively the same in terms of the timeline for propellant load and flight; however, there are some differences.

Overall, the propellant load is about 50 seconds slower, with Ship Liquid Methane (LCH4) load starting at T-49:50 rather than T-49:00. However, Booster Liquid Oxygen (LOX) load is 2 minutes and 57 seconds faster than Flight 4.

A few other timing changes exist. These are most likely just SpaceX refining the propellant loading for the Starship and Booster.

Flight 5 Timeline Credit: SpaceX

Flight 5 will have different milestone timings, including an interesting element for the flight director. The Most Engines Cutoff (MECO) is eight seconds earlier than on Flight 4, occurring at T+02:33. This makes the hot stage ring jettison and the boostback burn a bit earlier in the timeline as well.

This is likely related to trying to bring the booster back to the launch site.

As stated, this flight will also have a hot stage ring jettison like Flight 4, which will likely be a mainstay for many upcoming launches, ahead of the Flight 4 note that the HSRs will eventually become an integrated part of the booster.

For this flight’s big milestone, T+06:56 is labeled Super Heavy landing burn shutdown and Catch Attempt. This will not be an automatic piece of software directing the booster to make a catch attempt.

Infographic detailing sequence of events for Starship's Fifth Flight Test

Trajectory Graphic provided by SpaceX for Flight 5 of Starship Credit: SpaceX

To get the booster to return to the launch site for a catch, the Flight Director will have to send a manual command to the booster before the boostback burn is completed. This will then tell Booster 12 to attempt a catch and land at the Launch Site.

However, the software will auto-abort the catch attempt if either the booster or the chopsticks find something unhealthy with any system deemed required for a catch.

Flight 6:
If this were to occur, Booster 12 would perform a soft splashdown in the Gulf of Mexico if, by design, it is early enough in the landing profile. 

Besides trying for a catch attempt, the flight profile aims to end with a splashdown in the Indian Ocean with Ship 30, the same as Flight 4. SpaceX will try for a better reentry with Ship 30, which may be possible due to the new heat shield.

Launch License

The Federal Aviation Administration has now released a Launch License revision for Flight 5 of Starship, which was required because of the catch attempt. It dropped on Saturday, Oct 12.

It also included news that the approval also covers Flight 6 of Starship, which is expected to involved Booster 13 and Ship 31.


Ship 30 and Booster 12 Changes

Ship 30 will fly as the second stage for this mission and has been significantly upgraded over Ship 29, specifically with a new heat shield construction.

Due to the issues Ship 29 suffered during Flight 4, SpaceX replaced almost all of the tiles on Ship 30 with newer and stronger tiles. This will allow the tiles to withstand reentry and flight better.

The most significant change is the new secondary heat shield, an ablative material added under most pinned tiles in the most heat-affected areas. On ships like Ship 29, the setup used to be from bottom to top, felt, mesh, and then tiles. The new design is felt, mesh, ablative material, and then tiles. 

Ship 30 Nose Cone Tile Work (Credit: Sean Doherty for NSF/L2)

The felt is an insulator that helps close any gaps between the tiles. The mesh helps hold down the felt, making it easier to install the tiles. The ablative material is believed to be pryon, a carbon composite-like material. This will act as a secondary heat shield should the tiles fail.

Another addition is using more gap filler material around the flaps and flap fairings to prevent what happened to Ship 29 from happening again.

Other additions include four new cameras that look directly at the flaps and cameras in the flap hinge that look directly at the point of failure for Ship 29’s forward flap. 

Booster 12 changes with Ship 30 being Destacked (Credit: BocaChicaGal for NSF/L2)

In terms of Booster 12, there aren’t many noticeable visual changes. It is expected, as always, that teams have made hundreds of small internal modifications on each vehicle. Of the changes that can be seen, SpaceX has upgraded the last two Starlink antennas on the top of the chines, making all four the newer square design. Some new thermal protection was added to the bottom of the engine shielding.

For the catch, SpaceX has added tapered stringers over the chopstick stabilization points on the booster so that the new bumpers can slide up the booster during catch operations. These, plus the tapered stringers just below the lifting pins, have also been painted black so that SpaceX can see how the booster and chopsticks interact should a catch happen.

Orbital Pad A Changes

Along with vehicle changes, Orbital Launch Pad A has also seen changes. Almost all of the changes concern preparations for the catch. The only significant change unrelated to the catch is the removal of the Methane Recondenser vent, as crews continue to simplify the Orbital Tank Farm.

Crews have worked for months to add reinforcements to most of the chopsticks’ major weld lines. These will help strengthen the chopsticks’ structure and carriage assemblies ahead of catch operations.

Crews Installing Reinforcements onto the Chopsticks following testing (Credit: BocaChicaGal for NSF/L2)

Crews have also added newer compressable steel bumpers to the landing rails, replacing the older rubber-style ones that would get damaged during flight operations. Teams have also added shielding around the main chopstick actuators and their valve manifolds and shielding around most of the wiring, pneumatic, and hydraulic lines.

In addition, to make the landing rails capable of handling landing loads, more pistons were added to help cushion the booster as it lands. 

Larger Gusset Plates Installed at the top of Tower A (Credit: Jack Beyer for NSF/L2)

SpaceX has also upgraded the tower itself. Newer and larger gusset plates have been added near the top of the tower to help deal with the bending loads of catching. Gusset plates help connect the horizontal and diagonal truss beams for the tower.

SpaceX has spent tens of thousands of hours preparing the launch pad for this catch attempt. 

The Catch

The big question about the catch is how SpaceX will complete this feat of engineering. Assuming the flight director gives the go-ahead to try for a catch, the booster will glide back to the launch site after the boost-back burn. Once it is about one kilometer above the ground, all 13 center engines will fire to slow down the vehicle quickly.

Once sufficiently slowed, the middle ring of 10 engines will shut off, and the booster will complete its descent with the center three engines. As the booster travels between the chopsticks, the sticks will start to close fast and “slap” the booster somewhere above the common dome. The booster will then slide down the new bumpers until the landing pins come in contact with the landing rails.

The landing rails will compress, absorbing the shock of the landing until they are fully down. Once this is all done, the chopsticks will use a pair of jackscrews to translate the booster and line it up with the stabilizer pins. After it is aligned, these will engage, and then the booster will begin safeing procedures.

After the vehicle is safe, the booster transport will roll to the launch site to take the booster.

SpaceX has been preparing for this moment for years, and it is an essential component of getting Starship fully operational. Pulling this off will be one of the most extraordinary feats of engineering and spaceflight.

(Lead image: Flight 5 full stack Credit: Max Evans for NSF/L2; L2 includes full res full collection of all photos taken by NSF photographers.)

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