Booster 18.3 (B18.3) was a Block 3 Booster Test Tank designed to verify the structural integrity of the integrated hot staging ring design that will be used on the next generation of Boosters. It had an anomaly during a cryo test when it was detanked. The lower part of the common dome (an unpressurized part) expirienced a structural failure, and was shortly cut in half. The tanks forward section with hot stage truss was cut off and is now located in Starfactory
History[]
Parts for a new test tank were spotted in Starfactory on August 25th, 2025 from a video from Elon Musk of the inside of Starfactory shared prior to Starship Flight 10. A Booster forward dome section and common dome section were then stacked on August 27th, 2025 and received the unofficial community designation of TT19, as the 19th standard diameter Starship test tank produced by SpaceX following the continuation of the original TT1 and TT2 naming convention.
Subsequently on August 31st, 2025 a label was spotted on TT19, designating it B18.3.
B18.3 was lifted onto the original can crusher test stand on September 12th and moved out of MB1 on it on September 16th.
After some rounds of testing a two ring ship skirt with can crusher interface was rolled out to the Massey Outpost from 29-30 December 2025. B18.3 subsequently suffered an anomly while preforming a testing with the skirt installed on January 20th, 2026, either as a deliberate test to failure or an unexpected failure.
Timeline[]
- 25 Aug: B18.3 Parts spotted in Starfactory
- 27 Aug: B18.3 FX:3 stacked on CX:3 creating B18.3 F:5
- 31 Aug: B18.3 Label spotted
- 5 Sep: B18.3 F:5 rolled out of the Starfactory
- 5 Sep: B18.3 CX:5 rolled out of the Starfactory
- 6 Sep: B18.3 CX:5 moved into MB1
- 6 Sep: B18.3 F:5 moved into MB1
- 12 Sep: B18.3 lifted onto the first can crusher
- 16 Sep: B18.3 moved out of MB1
- 20 Sep: B18.3 rolled to Massey's
- 25 Sep: B18.3 cryo aborted during fueling
- 26 Sep: B18.3 cryo
- 29 Sep: B18.3 cryo
- 7 Oct: B18.3 cryo
- 14 Nov: B18.3 cryo
- 15 Nov: B18.3 cryo
- 17 Nov: B18.3 cryo
- 29 Dec: B18.3 LS:2 moved out of Starfactory into the ringyard
- 29-30 Dec: B18.3 LS:2 moved to the Massey Outpost
- 2nd January 2025: LS:2 stacked onto M:10
- 6 Jan: LS:2 removed from B18.3 at Massey's
- 9 Jan: LS:2 stacked onto M:10
- 9 Jan: Cancrusher cap onto LS:2
- 20 Jan: B18.3 tested to failure or had an anomaly during testing.
- 27 Jan: LS:2 removed from B18.3
- 3 Feb: B18.3 cut in half
- 4 Feb: B18.3 F:5 moved back to the build site and into Starfactory
- 5 Feb: B18.3 MX:5 removed from original structural test stand
Testing Campaign[]
| Date | Test type | Outcome | Details |
|---|---|---|---|
| 25 September 2025 | Cryogenic proof test | Unknown | B18.3 conducted a brief cryogenic proof test, with detanking starting early after a drone inspection, potentially indicating an abort but confirmation not possible. |
| 26 September 2025 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 29 September 2025 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 7 October 2025 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 14 Novemeber 2025 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 15 November 2025 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 17 November 2025 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 17 January 2026 | Cryogenic proof test | Success | B18.3 conducted a cryogenic proof test |
| 20 January 2026 | Cryogenic proof test | Structural Failure | B18.3 conducted a cryogenic proof test but had a structural failure at the lower part of the common dome section |
Gallery[]
