SpaceX Starship from V1 to V4

Key Takeaways

• Starship shifted from flight-test hardware toward a reusable transportation system.
• V3 introduced major reuse, docking, propellant-transfer, and pad-interface changes.
• V4 remained planned as of May 26, 2026, with a longer Ship and 42 total engines.

Starship and Super Heavy Version Families

SpaceX’s Starship and Super Heavy program had moved through four recognizable vehicle families by May 26, 2026: early atmospheric prototypes, V1 or Block 1 integrated flight-test vehicles, V2 or Block 2 higher-capacity vehicles, and V3 or Block 3 vehicles tied to SpaceX’s newer reuse and propellant-transfer design path. A V4 or Block 4 version had also entered public discussion as a planned future configuration rather than a flown vehicle. SpaceX’s Twelfth Flight Test launched on May 22, 2026, from Starbase, Texas, and marked the first flight of the V3 Starship and Super Heavy architecture.

The terminology can be confusing because “Starship” can mean the entire launch system or the upper-stage spacecraft. The full system combines the Super Heavy booster with the Starship upper stage, also called Ship. “V1,” “V2,” “V3,” and “V4” are convenient generation labels, but SpaceX discussions, launch observers, and regulatory material also use block names, ship numbers, and booster numbers. A useful comparison separates the stage, the version, the mission role, and the level of evidence behind each specification.

V1 carried the first full-stack test campaign. It helped SpaceX learn how the system behaved under ascent loads, stage separation, hot staging, engine restart attempts, reentry heating, and booster return profiles. V2 increased vehicle capability and introduced changes to the upper stage, including higher propellant capacity and altered forward flaps. V3 made a larger step by introducing Raptor 3 engines, major booster packaging changes, docking-related hardware, propellant-transfer connections, and a new launch pad architecture.

V4 is different from the other versions because it had not flown by May 26, 2026. An Elon Musk statement on X described a significantly longer Ship, three additional Raptors on the upper stage, a full-stack engine count of 42, and a planned 2027 flight. That made V4 an announced development direction rather than flight-demonstrated hardware. Any comparison of V4 needs to label its figures as planned or stated targets, not completed performance.

This table compares the main Starship and Super Heavy generations, separating flown versions from the planned V4 configuration.

Upper Stage Changes from Prototypes to V4

The upper stage changed more visibly than the booster because it had to solve more mission types. Starship must work as a second stage, spacecraft, reentry vehicle, payload carrier, tanker, depot element, lunar lander derivative, and possible Mars transport architecture. Early prototypes tested tank strength, stainless-steel manufacturing, landing burns, aerodynamic flaps, and the belly-first descent profile. Those vehicles did not represent an operational launch system, but they shaped the flight-control and thermal-protection problems that later versions had to solve.

V1 upper-stage vehicles carried the first integrated flight-test burden. They tested ascent, stage separation, engine cutoff, coast behavior, reentry heating, flap control, and ocean landing profiles. V1’s role was to expose failure modes under full-stack conditions. That meant engine reliability, propellant management, structural heating, tile retention, and stage separation were more important than payload service.

V2 increased upper-stage propellant capacity and changed the forward flap arrangement. The flap changes reduced exposure to the hottest reentry environment by shifting the flaps away from the windward side. V2 also helped SpaceX test Starlink simulator deployment, engine relight objectives, and high-energy reentry behavior. The version was still a development vehicle, but it moved Starship from basic survival to mission-relevant experiments.

V3 changed the upper stage into a platform aimed at refilling and reuse. During Flight 12, Starship successfully deployed 20 Starlink simulators and two modified Starlink satellites that imaged the vehicle during flight. SpaceX used that mission to test deployment through the payload door and to gather imagery relevant to reuse inspection. Flight controllers skipped the planned in-space engine relight test after the upper stage lost one engine during ascent, which showed that V3 had entered testing but had not yet completed every intended demonstration.

V4 adds a different kind of comparison because it was not flight hardware by May 26, 2026. Musk’s public statement described V4 as a 42-engine full stack created by adding three more Raptors to a significantly longer Ship. Since the Super Heavy booster already uses 33 engines, the statement points to a Ship with nine engines, most likely three sea-level engines and six vacuum-optimized engines. That planned arrangement would increase upper-stage thrust and support higher-energy missions, heavier payloads, and tanker-related objectives. It should still be treated as a target until SpaceX publishes detailed specifications or flies the vehicle.

This table compares Starship upper-stage versions from early prototypes through the planned V4 configuration.

Super Heavy Booster Development from V1 to V4

Super Heavy’s job is narrower than the upper stage’s job, but the physical demands are severe. The booster must lift the fully fueled stack, shut down and throttle engines in a controlled sequence, separate from Starship, reorient, restart engines, manage high heating during descent, and return either to the ocean or the launch tower. A full-stack Starship launch cannot become routine unless the booster becomes dependable and fast to inspect.

V1 Super Heavy established the 33-engine layout. The outer engine ring supplies much of the liftoff thrust, and the inner engines provide steering through thrust-vector control. Early boosters tested ascent stability, engine-out behavior, hot staging, boostback, and landing burns. The first booster catches showed that the tower-catch concept could work, but early catches did not remove the need for repeated flight data and refurbishment learning.

V2 supported higher-confidence recovery testing and early reuse. A reused Super Heavy booster flew during the V2 period, which showed that SpaceX had begun testing booster economics and inspection workflows rather than treating every booster as a one-off article. Booster reuse depends on engine life, heat protection, structural margins, landing precision, ground equipment, and access time between flights.

V3 changed the booster’s external and internal layout. Flight 12 used a V3 Super Heavy booster and a new hot-stage approach in which separation hardware was secured to the top of the booster rather than discarded as an interstage ring. The booster on Flight 12 was not intended for tower catch because SpaceX treated the first V3 launch and first Pad 2 launch as a risk-reduction flight. The booster did not complete its intended boostback profile and ended its mission in the Gulf area assigned for the test.

V4’s booster details were less defined than its upper-stage change by May 26, 2026. Musk’s 42-engine statement points to three additional engines on the longer Ship, not a change in Super Heavy’s 33-engine count. That means V4 should not be described as a 42-engine booster. It should be described as a 42-engine full stack unless SpaceX later publishes a different booster design. The most reasonable V4 booster expectation by May 26, 2026, was continued refinement of V3-style booster reuse, pad interface, engine reliability, grid fin protection, and catch operations.

This table compares the Super Heavy booster generations and distinguishes confirmed V3 changes from V4 assumptions.

Engine Counts, Raptor Versions, and Thrust Direction

The Raptor engine family defines Starship because it uses liquid methane and liquid oxygen in a full-flow staged-combustion cycle. Methane supports cleaner engine operation than kerosene and gives the program a conceptual link to future Mars propellant production. The full-flow staged-combustion cycle is technically demanding because both propellants pass through preburners before entering the main chamber, but it supports high chamber pressure and reuse-oriented performance.

Early Starship test vehicles flew with earlier Raptor designs. V1 and V2 vehicles used Raptor 2 and upgraded versions of that engine family across the integrated flight-test campaign. Raptor 2 simplified plumbing compared with earlier Raptors and gave SpaceX enough thrust to operate the 33-engine Super Heavy booster and six-engine Ship architecture. That configuration let the program test full-stack ascent, staging, coast, reentry, and landing behavior.

V3 introduced Raptor 3 as a vehicle-level redesign, not just an engine swap. Published descriptions of the V3 system emphasized higher thrust, cleaner packaging, fewer exposed external systems, and reduced reliance on large protective shrouds. Flight 12 demonstrated V3 hardware in flight, although the mission also showed that a new version can reach its major path targets and still experience engine losses. That is normal in a development campaign, but it prevents any claim that V3 had reached operational maturity by May 26, 2026.

V4’s 42-engine full-stack count is the biggest headline number. The math is straightforward: 33 engines on Super Heavy plus nine engines on Ship equals 42. The three added Ship engines would likely be vacuum-optimized engines because the upper stage already uses three sea-level engines for landing and atmospheric control. More vacuum engines would improve high-altitude and in-space thrust, which matters for payload delivery, tanker operations, and mission profiles that demand stronger upper-stage performance.

Raptor 4 was less firmly defined than Starship V4 as of May 26, 2026. Public speculation has linked a future Raptor version with higher thrust, but SpaceX had not published a full Raptor 4 specification by that date. A careful comparison should avoid treating unverified Raptor 4 thrust claims as established numbers. The better wording is that V4 points toward a longer, higher-capacity architecture and may be associated with later Raptor improvements if SpaceX completes and discloses that engine path.

This table compares the engine architecture across the main full-stack Starship generations.

Flight-Test Milestones That Separate the Versions

The first integrated Starship and Super Heavy launch on April 20, 2023, proved that the combined vehicle could lift off, but it also exposed pad and vehicle issues that shaped later redesigns. Early V1 missions helped SpaceX work through stage separation, engine reliability, flight termination behavior, ascent loads, and ground-system damage. The value of those flights came from data, not mission completion.

Flight 4 in June 2024 changed the public interpretation of the test campaign because the booster achieved a soft splashdown and the upper stage survived reentry long enough to complete a controlled splashdown. Flight 5 then demonstrated a tower catch of Super Heavy, which moved booster recovery from a design promise into a flight-demonstrated method. The tower catch matters because it allows SpaceX to avoid landing legs on Super Heavy and to build booster recovery into the launch infrastructure itself.

V2 flights pushed the vehicle into more complex testing. They tested Starlink simulator deployment, engine relight objectives, booster reuse, and different thermal-protection experiments. Some V2 flights ended with vehicle losses, which kept the generation within a development frame. The failures still narrowed engineering work by identifying weaknesses in propulsion, attitude control, payload-door operation, reentry behavior, and restart reliability.

Flight 12 marked the first V3 flight. The vehicle launched from Starbase’s second pad on May 22, 2026. The mission deployed 22 payloads, including 20 Starlink simulators and two modified Starlink spacecraft with cameras intended to inspect Ship 39’s heat shield. Super Heavy did not complete its intended boostback profile, and Ship 39 lost one of its six engines during ascent, but the Ship reached space and performed a controlled descent profile before ocean impact.

V4 had no flight milestone by May 26, 2026. Its place in the chronology is forward-looking. Musk’s public statement pointed to a 2027 flight, a longer Ship, and 42 total engines. That gives V4 a clear planning identity but no flight record. The distinction matters because Starship’s development history shows that announced versions can shift before flight as testing changes priorities, pad work reveals constraints, or mission needs change.

Payload, Propellant Transfer, and Mission Variants

Starship’s version changes matter most because SpaceX is not building a single-use launch vehicle. The company describes Starship as a fully reusable transportation system designed to carry more than 100 metric tons to Earth orbit in reusable form. That figure describes the design target for the system, not a fully mature operational record as of May 26, 2026. The path from flight tests to routine payload delivery still depends on payload deployment, orbital insertion, recovery, inspection, and relaunch cadence.

V1 had limited payload relevance because it focused on ascent, staging, and survival. V2 made payload testing more visible through Starlink simulator deployments. V3 sharpened that path through faster Starlink deployment hardware and heat-shield imaging satellites. The use of two operational Starlink spacecraft to inspect the upper stage on Flight 12 showed how SpaceX may connect its communications constellation, vehicle telemetry, and reuse workflow.

The tanker and depot versions depend more directly on V3 and V4-type hardware. NASA’s Human Landing System work with SpaceX requires Starship HLS to be refilled before it can support a lunar landing mission. NASA has stated that SpaceX must demonstrate an uncrewed lunar landing before crewed Starship HLS operations. Ship-to-ship propellant transfer remains one of the largest remaining technical tests for the architecture.

V4’s planned longer Ship and nine-engine upper stage would matter most for higher payload mass, tanker performance, and mission flexibility. A longer Ship can carry more propellant or support a larger mission-specific configuration, depending on final design. Extra vacuum engines could reduce burn time and improve high-energy mission performance. Those advantages remain conditional until SpaceX publishes official specifications and flies V4 hardware.

Defense and security users will watch these version changes through launch capacity, responsiveness, resilience, and schedule reliability. A reusable heavy-lift system could affect large-payload launch, constellation replenishment, logistics experiments, and national-security mission planning. That said, defense and security adoption would require reliability, range coordination, mission assurance, and regulatory confidence. V4’s planned capacity may interest government users, but no planned capability can substitute for repeated successful flights.

This table compares major Starship mission variants and how each version supports them.

Launch Sites, Pad Interfaces, and Regulatory Limits

Starship versions cannot be evaluated apart from launch infrastructure. Starbase’s first orbital launch mount supported the early integrated test campaign, but the pad and surrounding ground systems had to change after early flights. Flame management, water deluge operations, quick disconnects, tower catch hardware, propellant farms, and access procedures affect how often Starship can fly. A rocket designed for reuse still depends on a pad that can survive repeated launches and recover quickly.

Pad 2 became part of the V3 story because SpaceX launched the first V3 vehicle from the new pad. Flight 12 was the first Starship launch from Starbase’s second pad. That flight allowed SpaceX to test the new pad and vehicle together rather than treating them as separate systems. The decision not to catch the booster on that first V3 flight reflected the risk of damaging a new launch pad during a test mission.

Regulation also shapes the difference between a flown test vehicle and an operational launch service. The Federal Aviation Administration completed environmental review work for expanded Starship/Super Heavy activity at Boca Chica, including an April 2025 final tiered environmental assessment for up to 25 annual orbital launches and associated landings at the site. The environmental process does not by itself grant unlimited flight authority. SpaceX still needs licenses and approvals tied to public safety, financial responsibility, airspace, maritime risk, and mishap review.

V4 will likely depend on launch infrastructure more than any earlier version. A longer Ship changes handling, stacking, ground access, wind sensitivity, load paths, and pad compatibility. If the upper stage gains three additional vacuum engines, SpaceX will also need ground support and test infrastructure that can handle altered plumbing, thermal protection, checkout, and inspection work. The vehicle may be the headline, but the launch site determines how often it can turn that design into flights.

Florida will influence the broader Starship version comparison because high-cadence Starship operations cannot depend indefinitely on a single coastal Texas test site. Kennedy Space Center and Cape Canaveral activity can distribute operational load and create more access to national-security, NASA, and commercial launch demand. That expansion requires its own environmental reviews, construction, range coordination, and pad-readiness milestones. V4’s larger scale would make that infrastructure problem more demanding.

Commercial, NASA, and Space Economy Implications

Starship’s version history is a useful map of SpaceX’s commercial priorities. V1 created a full-stack test article. V2 increased mission complexity. V3 introduced hardware relevant to reuse, refilling, heat-shield inspection, and higher-cadence launch infrastructure. V4 points toward a larger upper stage and higher total engine count, which would raise the ceiling for payload, tanker, and deep-space mission planning if SpaceX can make the system reliable.

For Starlink, larger Starship versions matter because satellite mass, volume, and deployment rate affect network growth. Falcon 9 built the Starlink constellation’s first large deployment phase, but Starship offers a path to larger satellites and larger batches. V3’s deployment tests and heat-shield inspection satellites show how Starship and Starlink can support each other: Starship can deploy Starlink hardware, and Starlink can help monitor Starship during flight.

For NASA, the most direct implication remains the Artemis lunar lander. Starship HLS depends on refilling and docking demonstrations before it can support crewed lunar missions. V3’s docking interfaces and propellant-transfer features support that path. V4’s longer Ship and planned upper-stage engine increase could reduce the number of tanker flights or improve mission margins, depending on final design, dry mass, propellant capacity, and mission profile. Those benefits should be treated as possible, not proven.

Commercial satellite operators may see Starship versions through price, volume, schedule, and risk. A fully reusable Starship could change the economics of large spacecraft, orbital platforms, and high-volume satellite deployment. The market will not respond only to SpaceX’s performance claims. It will respond to flight rate, insurance treatment, demonstrated payload delivery, orbital accuracy, rideshare policies, and the ability to book missions without long delays.

Defense and security markets may place value on rapid replenishment, large-payload launch, and resilient space architectures. Starship could support larger spacecraft, distributed constellations, logistics demonstrations, and responsive launch concepts. Yet government adoption will depend on mission assurance, cybersecurity, export controls, pad security, launch licensing, orbital debris practices, and the ability to recover from failures without long grounding periods.

Summary

SpaceX’s Starship and Super Heavy versions show a program changing from experimental prototypes into a staged reusable transportation system. V1 proved that the full stack could fly and exposed the problems of launch pad survival, staging, propulsion reliability, and reentry. V2 increased capability and tested more mission-relevant functions, including payload deployment and engine relight work. V3 introduced a larger design shift through Raptor 3, Pad 2, docking-related features, propellant-transfer connections, heat-shield inspection support, and booster changes tied to future reuse.

V4 belongs in the comparison as a planned architecture, not a completed vehicle. Its defining public claims by May 26, 2026, were a longer Ship, three added upper-stage Raptors, 42 total engines across the full stack, and a planned 2027 flight. That means V4 should be described carefully: it is a stated development direction that could raise payload, tanker, depot, and deep-space performance, but it had not yet produced a flight record.

The most meaningful comparison is not only bigger versus smaller or newer versus older. Each version addresses a different barrier. V1 addressed full-stack flight. V2 addressed higher-capability testing. V3 addresses reuse, inspection, refilling interfaces, and upgraded launch infrastructure. V4 appears directed at scaling the architecture beyond V3. The program’s next test is whether these hardware generations can turn into repeatable service for Starlink, NASA, commercial payloads, and government missions.

Appendix: Top Questions Answered in This Article

What Is the Difference Between Starship and Super Heavy?

Starship is the upper-stage spacecraft and second stage of the launch system. Super Heavy is the first-stage booster that lifts Starship from Earth. SpaceX also uses Starship as the name of the full two-stage system, so version comparisons need to specify whether they refer to the Ship, the booster, or the full stack.

What Did V1 Prove?

V1 proved that SpaceX could launch a full Starship and Super Heavy stack and gather data from real ascent, staging, reentry, and recovery attempts. It did not prove routine launch service. Its main value was showing which parts of the system needed redesign after exposure to full-flight conditions.

How Did V2 Improve on V1?

V2 increased upper-stage capacity, changed flap placement, improved avionics, and supported more complex flight-test objectives. It helped SpaceX test payload deployment, engine relight work, booster reuse, and reentry behavior. V2 still remained a developmental generation rather than a regular service vehicle.

Why Is V3 a Larger Step Than V2?

V3 introduced Raptor 3, Pad 2 operations, docking interfaces, propellant-transfer connections, heat-shield inspection support, and major booster changes. These features connect directly to reuse, orbital refilling, lunar missions, and higher launch cadence. V3 entered flight testing on Flight 12 in May 2026.

What Is Starship V4?

Starship V4 is a planned future version publicly described as a longer vehicle with 42 total engines across the full stack. The count comes from 33 Super Heavy engines and a planned nine-engine Ship. As of May 26, 2026, V4 had not flown and should be treated as planned hardware.

Does V4 Mean Super Heavy Will Have 42 Engines?

No. The 42-engine figure refers to the full stack based on public statements, not the booster alone. Super Heavy already uses 33 engines. The additional three engines are associated with the Ship, which would move from six to nine engines if SpaceX implements the stated V4 plan.

Why Does Starship Need Propellant Transfer?

Starship needs propellant transfer for missions beyond low Earth orbit, especially lunar landing operations. A Starship lunar lander cannot complete the planned mission profile on a single launch from Earth. Tanker and depot operations would refill the vehicle before it departs for higher-energy destinations.

Why Does Pad 2 Matter to V3?

Pad 2 matters because V3 is part of a combined vehicle and ground-system redesign. A reusable rocket depends on launch mounts, catch arms, propellant systems, flame control, quick disconnects, and inspection access. Flight 12 tested V3 and Pad 2 together for the first time.

Is Starship Operational as of May 26, 2026?

Starship remained in developmental flight testing as of May 26, 2026. V3 had flown, but routine payload service, ship reuse, orbital propellant transfer, depot operations, and crewed lunar use still required more demonstrations. Planned V4 improvements did not change that operational status.

Which Version Matters Most for Artemis?

V3 matters because it introduces docking and propellant-transfer interfaces that support the Artemis Starship HLS path. V4 could improve margins if its planned longer Ship and nine-engine configuration reach flight. The Artemis role still depends on uncrewed lunar landing, refilling, docking, and reliability demonstrations.

Appendix: Glossary of Key Terms

Starship

Starship is SpaceX’s upper-stage spacecraft and second stage. The same name also refers to the full two-stage launch system when paired with Super Heavy. The distinction matters because version changes can affect the Ship, the booster, or the complete stack.

Super Heavy

Super Heavy is the first-stage booster that lifts Starship from Earth. It uses 33 Raptor engines and is designed for recovery through controlled descent and eventual tower catch. Its development focuses on thrust, staging, engine restart, heat protection, and reuse.

Raptor

Raptor is SpaceX’s methane and liquid oxygen rocket engine family. It powers both Starship and Super Heavy. Later Raptor versions focus on higher thrust, simpler packaging, lower mass, and better integration with reusable vehicle systems.

Hot Staging

Hot staging means the upper stage begins engine ignition before it fully separates from the booster. This can improve performance but exposes the booster top to engine exhaust. V3 uses an integrated hot-stage approach rather than the earlier disposable interstage concept.

Grid Fin

A grid fin is an aerodynamic control surface used to steer Super Heavy during descent. V3 moved toward three enlarged fins with revised protection and catch features. Grid fin design affects booster control, heating, and tower-catch precision.

Pad 2

Pad 2 is the newer Starbase launch pad used for the first V3 flight. It supports the upgraded vehicle with revised launch, flame-management, propellant, and catch-related infrastructure. Starship’s reuse model depends on pad systems as much as rocket hardware.

Propellant Transfer

Propellant transfer is the movement of fuel and oxidizer from one spacecraft to another. Starship requires this capability for lunar missions and other high-energy destinations. Tanker and depot versions depend on docking, cryogenic storage, and reliable transfer plumbing.

Starship HLS

Starship HLS is the Human Landing System version of Starship being developed for NASA’s Artemis program. It is intended to carry astronauts between lunar orbit and the lunar surface after being refilled through Starship tanker and depot operations.

V4 Or Block 4

V4, also called Block 4 in some discussions, is a planned future Starship configuration. Public statements describe it as a longer Ship with three additional Raptors, creating a 42-engine full stack. It had not flown by May 26, 2026.