Firefly to upgrade Alpha rocket to improve reliability

WASHINGTON — Firefly Aerospace says it will upgrade its Alpha launch vehicle, making changes intended to improve the reliability of a rocket that has experienced several failures.

The company announced Jan. 13 that it will begin flying a Block 2 version of Alpha starting with Flight 8. The next launch of the rocket, Flight 7, will be the final flight of the current configuration.

“The Block 2 upgrade has been part of Firefly’s strategic growth plan to meet the evolving needs of the global launch market and further supports Firefly’s culture of continuous improvement with a focus on enhanced safety, quality and reliability,” Jason Kim, Firefly’s chief executive, said in a statement.

The most visible change in Alpha Block 2 will be stretched first and second stages. The first stage will increase in length from 18.4 meters to 20.1 meters, while the second stage will grow from 6.0 meters to 6.3 meters.

The Block 2 version will also replace off-the-shelf batteries and avionics with a consolidated system developed in-house. Firefly is also modifying the vehicle’s propellant tanks, improving their thermal protection systems and “optimizing” the tank configuration to increase burn time.

The company did not disclose how the changes will affect payload performance. Alpha is currently listed as capable of carrying 1,030 kilograms to low Earth orbit and 630 kilograms to sun-synchronous orbit. Firefly said the upgrade “is designed to expand Alpha’s deployable launch capabilities” for responsive space missions, hypersonics testing and commercial satellite launches, but did not provide specific performance figures.

The company emphasized improvements to quality and reliability in the upgrade. “Firefly worked closely with customers and incorporated data and lessons learned from our first six Alpha launches and hundreds of hardware tests to make upgrades that increase reliability and manufacturability with consolidated parts, key configuration updates and stronger structures built with automated machinery,” Kim said.

Of the six Alpha launches to date, only two have placed payloads into their intended orbits. Two others deployed payloads into lower-than-planned orbits, limiting the operational lifetimes of those satellites.

The remaining two flights failed to reach orbit, including the most recent orbital launch attempt in April 2025. Firefly attributed that failure to higher-than-expected aerodynamic heating of the first stage during ascent, which caused a structural failure shortly after stage separation. The resulting pressure wave destroyed the upper stage’s nozzle extension, reducing the engine’s performance and preventing the vehicle from reaching orbit.

Firefly was preparing for Alpha’s return-to-flight mission, Flight 7, when the first stage for that vehicle was destroyed during a static-fire test Sept. 29. The company said in November that “minute hydrocarbon contamination” in one of the stage’s four engines caused the explosion, describing it as a quality lapse rather than a design flaw.

Firefly will instead use for Flight 7 the first stage originally built for Flight 8. The launch, from Vandenberg Space Force Base in California, is scheduled for the “coming weeks,” though the company did not provide a specific date. Some Block 2 system upgrades will be tested on Flight 7 in “shadow mode,” Firefly said.

Shares of Firefly Aerospace, which went public in August at $45 per share, closed at $27.97 on Jan. 13, down 8.1% for the day.