Relativity Space

Building reusable rockets to empower science, exploration, and innovation beyond our planet.

[Relativity Space @relativityspace]

🔥 Just another day at Stennis. Stage 2 successfully completed its first integrated hotfire!

The A2 test stand was originally built in the 60s to support Saturn V Upper Stage testing (S-II). It was later reconfigured to be a single engine test stand for Shuttle Main Engine testing and development.

The last Saturn V Stage test occurred October 30, 1970 on A2. It has been 55 years, 11 months, and 17 days since A2 supported stage testing capability.

As of this morning, it is now 0 days.

[Relativity Space @relativityspace]

Building the infrastructure to launch Terran R. September brought several key milestones across LC-16's launch pad and ground systems.

✔️ The east lightning protection system tower reached its full height of 530 feet.
✔️ Structural steel on the east side of the launch table is complete.
✔️ Permanent 480-volt power infrastructure energized at the pad.

[Relativity Space @relativityspace]

Full update➡️ https://t.co/oXcohFVJmo

[Relativity Space @relativityspace]

September was a big month for test operations across our sites.

📍 NASA Stennis, MS
Stage 2 completed its first wet dress rehearsal! The team put the stage through flight-like propellant loading, COPV fills, engine chill operations, and a simulated stage 1 ascent timeline, building toward its first integrated hot fire.

📍 Long Beach, CA
All 13 Aeon R engines are installed on the thrust structure and are moving through integrated gimbal testing, validating their ability to pivot precisely to steer and stabilize the vehicle during flight.

[Relativity Space @relativityspace]

P.S. Summer 2027 Internships are open. https://t.co/ThE0sbeuGG

[Relativity Space @relativityspace]

From tank integration to engine production, September builds kept the team busy.

✓ Installed the downcomer into the stage 1 flight tank
✓ All primary hardware on the stage 1 aft dome is complete, closing in on final integration
✓ Interstage drilling finished, now heading to the Tender Loving Crusher for structural testing
✓ First 2 ground station controllers stood up
✓ First welds complete for the Aeon V vacuum engine nozzle extension
✓ Flights 2 and 3 engines well into manufacturing with production ramping

[Relativity Space @relativityspace]

Watch the full September program update https://t.co/oXcohFVJmo

[Relativity Space @relativityspace]

From the downcomer going into the stage 1 tank to stage 2 completing its wet dress rehearsal at Stennis, September brought progress across every discipline.

🔩 Build: The downcomer was installed into the stage 1 flight tank. The interstage completed drilling and was passed off to the Tender Loving Crusher ahead of structural testing. Engine production continues to ramp, with articles for flights 2 and 3 well into manufacturing.
🧪 Test: With all 13 engines installed, the thrust structure transitioned into integrated gimbal testing. At Stennis, stage 2 completed a wet dress rehearsal on the A2 stand, building towards the first hot fire test.
🏗️ Launch: The east lightning protection tower reached its full height of 530 feet, the east launch table structural steel is complete, and permanent 480-volt power has been energized at the pad.

[Relativity Space @relativityspace]

LC-16 is taking shape.

✔️ Flame diverter installation is underway, built to redirect the immense heat, exhaust, and acoustic energy generated at launch.
✔️ Launch table steel is going up alongside continued work on the LNG tank farm and lightning protection system, raising the first sections of the 531-foot towers.
✔️ Inside the HIF, outfitting continues as the transporter erector upper strongback takes shape.
✔️ The engineering support building is officially open, giving the teams who will operate Terran R launch campaigns a new home on-site.

[Relativity Space @relativityspace]

The team is growing: https://t.co/WMhA0RqeDD

[Relativity Space @relativityspace]

Hardware across the vehicle continues to advance through test.

📍 Long Beach, CA
The first stage downcomer completed its full acceptance test campaign. This flight-critical component, which routes liquid oxygen from the tank to the engines, is now cleared for integration.

📍 NASA Stennis, MS
Stage 2 is back in the hangar after completing cryoproof and COPV proof testing. Post-test inspections are underway ahead of Aeon V installation. A2 is being prepped for hot fire, with LOX farm flushes and heat exchanger activations. On the R stand, acceptance testing of flight 2 Aeon R engines is underway.

[Relativity Space @relativityspace]

Full update https://t.co/apBxBcwBWv

[Relativity Space @relativityspace]

Terran R hardware is advancing across multiple fronts, with integration work progressing on stage one and production scaling for future vehicles.

✓ All 13 flight one Aeon R sea-level engines installed onto the thrust structure
✓ All nominal joiners and external stringers approaching completion on stage one
✓ Both interstage barrels were painted and stacked to form the full structure
✓ All flight two barrels complete, first circumferential friction stir welds executed on the flight two stage one tank
✓ Flight three panel fabrication more than halfway complete

[Relativity Space @relativityspace]

Watch the full August program update: https://t.co/apBxBcwBWv

[Relativity Space @relativityspace]

With all 13 Aeon R engines installed on the thrust structure and stage two heading towards hot fire, August was a big month for Terran R.

🔩 Build: All 13 Aeon R engines were installed onto the thrust structure. Stage one integration is advancing and both interstage barrels were stacked. Flight two barrels are complete and flight three production has begun.
🧪 Test: Stage two completed cryoproof and COPV proof testing and is now being readied for Aeon V engine installation ahead of hot fire.
🏗️ Launch: Flame diverter installation is underway at the pad, the engineering support building opened, and HIF outfitting continues.

[Relativity Space @relativityspace]

💫 Terran R has been selected for NASA’s Launch Services (NLS) II contract, making us eligible to compete to launch future @NASA science, planetary, and exploration missions. We’re excited to help unlock new frontiers of discovery beyond Earth.
Learn more: https://t.co/7zj9tuFTuj

[Relativity Space @relativityspace]

Join the team: https://t.co/qem6etKF8h

[Relativity Space @relativityspace]

The infrastructure required to launch a rocket of Terran R’s class is immense. At LC-16, we’re moving fast.

✓ Horizontal integration facility (HIF) is energized. This building will house Terran R's stages to be mated and prepared for launch
✓ 135 ton assembly room cranes completed their first proof load tests. These cranes will lift the vehicle for mate
✓ Transporter erector (TE) upper strongback was moved into the assembly room. This is part of the system that will transport Terran R to the pad and raise it vertical
✓ Permanent site power was activated with two dedicated 22-kilovolt feeds. This powers launch operations across the site

[Relativity Space @relativityspace]

https://t.co/ckUgFzhJ2G

[Relativity Space @relativityspace]

Test campaigns are building momentum, with major milestones logged across sites in July.

📍 Long Beach, CA
✔️ Stage one structural qualification campaign complete
✔️ 420 pressure cycles, 62 loading cases, and 4.3 million lbf axial compression
✔️ Stage one downcomer for flight completed first phase of acceptance testing

[Relativity Space @relativityspace]

📍 NASA Stennis, MS
✔️ Second stage lifted and mated onto the A2 stage test stand
✔️ Cryoproof and COPV proof testing complete
✔️ Aeon V engine completed acceptance testing, wrapping up all flight one engine testing