Starship Flight 13: Pad Abort Cause and 20 Starlink V3 Satellites

Starship Flight 13 was the second flight of the version 3 Starship, a fully stacked vehicle standing just over 407 ft tall, flying uncrewed from Starbase, Texas. The launch was targeted for 5:51 p.m. Central Time, after an earlier attempt ended at engine ignition: at T0, four of Super Heavy's 33 Raptor engines did not light, and the vehicle shut itself down safely. This is the pre-launch coverage, built from Everyday Astronaut's livestream and the SpaceX broadcast it carried.

The aborted first attempt

On the first attempt, SpaceX said the countdown was clean, all propellant was loaded, and the vehicle reached engine ignition before its automated systems detected an off-nominal startup on four engines. SpaceX's Dan Huot explained that the vehicle has a launch constraint allowing it to be down no more than two Raptor engines at liftoff. More than that were out, so it aborted before the final T0 and safely shut down all the engines that had started. SpaceX described it as a real-world test of an abort designed for one of the most critical dynamic phases of flight, in which 29 running Raptor engines were shut down safely.

SpaceX's review of the data showed an off-nominal spin response in the aux turbo pumps on six of the engines. These pumps pressurize and feed liquid oxygen into the engine for combustion. The most likely root cause, SpaceX said, was moisture collected inside the pumps from previous operations, which froze when cryogenic propellant was introduced and either slowed the pumps or stopped them from spinning. The engines were swapped; one was tested on a stand at McGregor and completed a full booster ascent burn. The Everyday Astronaut host, Tim Dodd, said he did not know the exact root cause when he was first asked about it, and had heard only that something like water or ice may have gotten in.

A further attempt planned for the day before was not flown. Huot said the cause was visibility, not launch weather constraints: a key goal of the flight was clear imagery of the ship's tiles at a higher dynamic pressure, and clouds would have obscured the ascent. He added that SpaceX is capable of, and legally allowed to, launch into lightning after testing and analysis, and will use that capability carefully.

The vehicle

SpaceX described the stack as a two-stage rocket, with both stages designed to return and fly again. Super Heavy is powered by 33 Raptor 3 engines running on liquid methane and oxygen. It has three grid fins, 50% larger than on earlier boosters, which steer it during landing. At the top sits the hot stage adapter, now fully integrated for reuse. The ship has six Raptor engines: three optimized for sea level and three for vacuum. For this flight the booster was Booster 20 and the ship was Ship 40, according to Dodd.

Propellant loading began at about T-35 minutes. Huot said about 11.5 million pounds of liquid oxygen and liquid methane would be on the two stages when loading finished, with booster loading closing at about T-2:50 and the ship at 2:10. The two smaller header tanks on the ship, used for the in-space burn and the landing burn, were loaded last. A new hold point was set at T-60 seconds. The flame diverter water on pad two activates at T-17 seconds, and a hold after that point means a scrub for the day. After T-60 seconds the count can be recycled to that point, with an estimated 5 to 8 minutes of hold time, largely set by propellant temperatures.

Flight plan

SpaceX listed the objectives as a successful liftoff, stage separation, deployment of 20 Starlink V3 satellites, a relight of a single Raptor engine, reentry, and soft splashdowns of both booster and ship, with the ship's splashdown in the Indian Ocean. Dodd said the profile was almost identical to Flight 12, the first V3 flight in May: the ship goes south of Cuba and around the Earth, then comes down off the coast of Australia. The Flight 12 ship had performed what looked like a 360-degree pirouette near the end; the spin was never officially confirmed as intentional, though Dodd said it looked deliberate and likely gave cameras views of the whole heat shield. He said the Flight 12 flight had no engine relight and the booster did not get its planned clean boost back and landing, and that the boost-back burn sequence was tweaked for this flight.

Dodd explained the hot staging logic: the booster is moving away from the pad at thousands of kilometers an hour at separation, so the faster it flips and relights engines for the boost-back burn, the less distance it has to recover. He gave a rough estimate of about 1.5 km per second for its drift. He put max Q at under a minute and booster engine cutoff at 2:18, and he expected a soft splashdown of the booster in the Gulf, simulating a tower catch without the tower.

The Starlink V3 satellites

The 20 satellites are real, operational-design units, but because the flight is suborbital they will be in space only about 20 minutes before demising. In that time the Starlink team planned to run tests such as deploying solar arrays, firing thrusters, extending antennas, connecting with ground stations and turning on communications systems. SpaceX said each Starship mission would add around 20 times the capacity of a Falcon launch of V2 satellites, and that the V3 design supports 1 terabit per second of downlink and 160 gigabits per second of uplink, roughly 10 times and 22 times the V2 figures. Each V3 satellite has six 400-gigabit space lasers, four quad-band radio backhaul antennas, and solar arrays producing about twice the power of V2. They are built at Starlink's site in Redmond, Washington.

What comes next

Dodd said the vehicle already has the propellant and thrust to reach orbit and is deliberately kept suborbital by a few hundred meters per second so it cannot become stuck in orbit. In his view, the remaining steps are another safe ship reentry, a booster re-entry and soft splashdown, and a Raptor relight, which he thought could push orbit to Flight 14 or 15. Booster catch, he guessed, might come by Flight 15. SpaceX said success would open the door to orbital flights and the first attempt to catch a ship on tower two at Starbase.

SpaceX also noted that NASA had announced the Artemis 3 crew of Andre Douglas, Luca Parmitano, Randy Bresnik and Frank Rubio for a crewed low Earth orbit demonstration slated for 2027, in which Starship with a docking port on its nose would rendezvous and dock with the crew.