Payload increased by 50%! Musk said SpaceX will upgrade Starship with more Raptor engines

SpaceX CEO Elon Musk said that future starships (or at least some starship variants) are being upgraded, adding 50 percent more Raptor engines and propellant storage tanks.

Musk confirmed that Starship could "add 3 engines." Currently, Starship has a total of 6 engines, plus a super heavy rocket booster with 33 engines, which will form a 39-engine behemoth. But Musk said it is possible to add 3 more engines to Starship, from 6 to 9, and substantially upgrade the storage tanks.

According to amateur modelers, they are usually able to estimate the rocket's performance by gathering enough information about the rocket's structure, shape, and engines, and the 9-engine Starship tank will be stretched by about 25 percent to store an additional 300 tons of cryogenic liquid oxygen and methane (LOx/LCH4). The upgraded Starship will have a lift-off mass of nearly 1600 tons and an altitude of about 55 meters, 10% higher than the current ship.

At the time of phase separation, a starship equipped with 3 sea-level optimized Raptor engines (RCs) and 6 vacuum-optimized Raptor engines (RVacs) should be able to generate at least 2,000 tons of thrust. Depending on the performance of the engine, it may exceed 2250 tons. With this higher thrust, Starship will be only 10 percent lower than the first stage thrust of the world's most powerful launchable rocket, the Falcon Heavy rocket.

Regardless of its thrust, size or weight, the most important thing is how the nine-engine Starship will affect the launch performance of the entire rocket. If the unofficial modelers are credible, the results are remarkable: compared to a "normal" starship equipped with 6 engines and 33 engine boosters, the augmented spacecraft could theoretically increase the payload that a rocket can launch into low-Earth orbit (LEO) from 150 tons to 220 tons or more, almost 50 percent higher.

If these estimates are accurate, it could slow down Starship's development, and equipping the spacecraft with nine engines would increase a considerable portion of the cost, but a 50 percent payload performance improvement would significantly improve the efficiency of Starship's more ambitious lunar and Mars launch configurations, which would require a lot of orbital fuel replenishment.

In fact, a 50% increase in payload will allow SpaceX to complete most refueling tasks more efficiently, faster, and cheaper. Even though the upgrade plan means that all starships will be extended and equipped with 9 Raptor engines, it may take 7 tankers instead of 8-10 for LEO's new spacecraft to be fully refueled. If SpaceX doesn't mind keeping multiple different starship variants, which seems to be true, then a spacecraft that relies entirely on fuel replenishment can maintain its current size, with about 1200 tons of propellant storage and 6 Raptor engines. As a result, an upgraded Starship fleet could refuel their smaller counterparts with 5-6 tankers.