Ship 36 explodes in static fire test
In preparations for SpaceX’s 10th test flight, Ship 36, the newest in the fleet, exploded in a huge fireball in South Texas on June 18. Sat on a test stand, the event occurred during the last few minutes of propellent load, just before it was set to perform a static fire test, where the 52 meter long ship is partially fueled and at least one engine is being ignited for a small duration to test engine startup while measuring pressure, temperature and propellant-flow gradients.
The Texas based company has already attempted two cryogenic proof tests and one static fire test with this ship, but only one of the six engines were ignited to simulate the in-flight relight of a Raptor engine. The catastrophic incident on Wednesday was meant to have all six engines fired up before Flight 10, which was scheduled to happen as soon as the end of the week, breaking the flight turnaround record that currently sits at just over a month (between Flight 5 and 6).
The two explosions destroyed the ship completely, the first one beginning in the payload bay and the second occurring moments later with the propellant igniting. Significant damage has also been reported to the Massey’s Testing Center to the test stand, including the SSF Stand (Ship Static Fire Stand), the Ship Fueling Gantry, fuel lines, and deluge tanks, pipes and manifolds, and debris has also been reported to have been found across the site and on the Rio Grande Riverside and RG coast. Although electrical bunkers and storage bunkers were damaged, and cryo tanks also sustained damage, Test Tank 18 appeared relatively undamaged, possibly due to its enclosure within the Massey's testing rig.
It is important to remember that SpaceX does impose and maintain a safety zone around the test site and that there were no reported injuries and all personnel were safe and accounted for. The explosion also did not pose any risk to the communities in the Rio Grande area as all materials on the Ship are tested for toxicity, especially in relation to chemical, biological or toxicological risks and conform to all applicable ecological and safety standards.
Initial data suggests that there was a failure in relation to a composite overwrapped pressure vessel (COPV) in the nosecone of Ship 36, where it potentially showed an issue in relation to the pressure being below rating. COPVs are carbon fiber-wrapped tanks that can hold various gases, such as nitrogen, helium, and oxygen, at high pressures, and are much lighter than steel tanks of similar size. Later on during Thursday, SpaceX gave a statement on its website swhere it said the preliminary analysis indicated “the potential failure of a pressurized tank known as COPV, or composite overwrapped pressure vessel, containing gaseous nitrogen in Starship’s nosecone area, but the full data review is ongoing.” There are many of these on the payload bay wall of the windward side of Starship, meaning that if one ruptured, it would have acted like a shaped charged charge and ripped the payload wall outward and resulted in the header tank transfer tubes that contain LCH4 and LOX to be ripped apart and instantly ignited, understandably making the nosecone of S36 collapse. This would have then triggered the rest of the propellant to ignite, causing a second explosion that left fires burning for several hours at the testing site and likely damaging the LCH4 farm at Massey’s.
The COPVs on Starship and Super Heavy are different to those used on the Falcon range, making it an isolated issue in the Starship program, especially involving the ship, that has seen many issues in the last few months, with both Flight 7, 8 and 9 resulting in RUDs. This incident also marks the first time SpaceX has lost a ship in ground testing since May 2020 with SN4.
As the anomaly occurred during ground testing, the FAA will not be involved in any investigations, but SpaceX will conduct its own investigation before completing any more Starship testing or flights. This will be conducted simultaneously with the ongoing Flight 9 investigation that is being overseen by the FAA.
The anomaly is certainly a huge setback for the iterative-design focused company and puts Elon Musk’s Mars 2026 target in a questionable situation. With the sudden loss of a ship that was nearly ready for flight and significant damage to the infrastructure needed to test Starship and Super Heavy, the upcoming months will nbot be easy for SpaceX and will most likely set back work on the Block 3 ship that Musk wanted to launch before the endo of this year. Without the facilities to do static fires, S37, which recently began receiving its engines, will be stuck in Mega Bay 2 alongside S38, which needs to undergo cryogenic testing before receiving engines, the chance of which is not clear if it is currently possible due to the extent of the damage at Massey’s.
As mentioned before, the Block 3 iteration of Starship is set to commence with S39, which is currently being engineered, it is unclear whether SpaceX will want to repair the infrastructure at Massey’s and then have to modify it after only two ships for the Block 3 configuration.
Looking back into the nearer future, B16, although ready to fly, has recently had its hot-stage ring removed, as it is very likely it won’t be flying anytime soon. B15 is also ready and waiting to go on its next flight, which will likely be the last flight of a Block 2 booster. This will make B17 redundant as SpaceX only has two Block 2 ships left. B18, which would be used in Block 3, was actually involved in the incident with its test tank caught in the explosion, likely sustaining some damage that would delay testing and production of the booster. The new booster thrust sim stand that was undergoing construction also looks as if it got charred in the explosion.
On top of the repair to the testing infrastructure, it is certainly possible that SpaceX will have to inspect and potentially redesign the COPV for its Starship fleet, making it likely that the program will see significant changes and delays for the foreseeable future. It is needless to say, though, that SpaceX will be ensuring to test and improve for Flight 10.
