Firefly Alpha FLTA007 “Stairway to Seven” ready for another launch attempt

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Firefly Aerospace is returning its Alpha launch vehicle to flight after a nearly 10-month stand down following the failed FLTA006 “Message In A Booster” mission in April 2025. FLTA007 “Stairway to Seven” is now scheduled to launch from the California coast no earlier than 5:50 PM PDT on Monday, March 9 (00:50 UTC on March 10).

The launch window lasts until 7:50 PM PDT on March 9 (02:50 UTC on March 10). The launch had been scheduled for Friday, Feb. 27, then Saturday, Feb. 28, and Sunday, March 1, but was postponed every time due to forecast high upper-level winds.

The “Stairway to Seven” mission was originally scheduled for Feb. 20, but a severe weather forecast for the west coast caused Firefly to postpone the launch for a week. FLTA007 will launch on a southwest trajectory from Space Launch Complex 2W (SLC-2W), a former launch pad for Delta II flights, on the north side of Vandenberg Space Force Base (VSFB).

The flight will not carry any payloads; its purpose is to test a number of modifications to the vehicle and to demonstrate its ability to perform a nominal ascent. Should the second stage reach low-Earth orbit (LEO), it will be in a retrograde orbit, going against the direction of Earth’s rotation.

The Alpha rocket will ignite its four Reaver engines, using kerosene and liquid oxygen as propellants, two seconds before liftoff to ensure everything is operating correctly. Once the rocket lifts off its pad at SLC-2W, the next major milestones will be reaching Mach 1, the speed of sound, at T+55 seconds, followed by maximum dynamic pressure (Max Q) at T+1:06 minutes. Main engine cut-off is at T+2:35 minutes, and stage separation at T+2:38 minutes.

Timeline of Firefly Alpha FLTA007’s flight. (Credit: Firefly Aerospace)

It is at this juncture that things appeared to start to go wrong for FLTA006 “Message In A Booster” last year. Just milliseconds after stage separation, the first stage ruptured, and the resulting pressure wave hit the second stage. This pressure wave caused the nozzle extension of the upper stage’s Lightning engine to shear off, significantly reducing the second stage engine’s thrust.

Even without its nozzle extension, the mission nearly succeeded, just missing orbital velocity by three seconds and the target orbit by five seconds before running out of propellant. A mishap investigation found that plume-induced flow separation caused excessive heating of the first stage on its leeward side, and stage-separation-induced loads led to the first stage’s rupture.

FLTA006 flew at a higher angle of attack than prior Alpha missions, and this angle of attack contributed to the excessive heating event. Corrective actions now implemented include increasing the thickness of the first stage’s thermal protection and reducing the rocket’s angle of attack during key flight phases.

Should FLTA007 have a nominal stage separation, the next key milestone is fairing separation at T+3:03 minutes. The Lightning engine will run until second-stage engine cutoff at T+8:02 minutes. All event times are approximate and may vary depending on flight conditions.

Firefly Aerospace’s Briggs, Texas, facility. (Credit: Gary Blair for NSF)

This mission’s road to the launch pad not only awaited the Federal Aviation Administration’s (FAA) clearance to fly following the “Message In A Booster” mishap but also the production of a replacement first stage following another mishap at Firefly Aerospace’s facility in Briggs, Texas.

On Sept. 29, a first stage — set for use on FLTA007″ Stairway to Seven” — was being tested at an outdoor stand in Briggs when it exploded after hydrocarbon contamination caused what Firefly termed a “combustion event” in one of the stage’s Reaver engines. The company identified a process error during the stage’s integration that resulted in the chain of events.

The company revealed a summary of its results on Nov. 12 and noted that it conducted a daylong quality stand-down in which teams reviewed and optimized existing procedures. Firefly also announced its implementation of corrective actions, including additional fluid system inspections, additional automated aborts, and optimizing the first stage’s sensors.

The test stand at Briggs remained intact despite the incident and is being upgraded, which the company hopes to complete this quarter. Firefly used another stage on its production line to support the “Stairway to Seven” mission and announced that it had shipped the stage to VSFB to join the second stage already there on Jan. 8.

Firefly erected the entire Alpha launch vehicle on the pad at SLC-2W in late January to prepare for a 20-second test firing and subsequent launch. On Feb. 6, the FLTA007 Alpha successfully test-fired its four Reaver engines for the full duration of 20 seconds.

FLTA007 “Stairway to Seven” will be the final Alpha Block 1 vehicle to fly, as the company is moving to the upgraded Alpha Block II with FLTA008 and subsequent launches. The “Stairway to Seven” flight will test not only the fixes applied to the first stage following “Message In A Booster” but also several key Block II systems.

A Firefly Alpha Block II second stage undergoing qualification testing in Briggs, Texas. (Credit: Firefly Aerospace)

Block II will use in-house avionics and batteries built by Firefly rather than off-the-shelf, and these items will be used across Firefly’s spacecraft and rockets. The Block II avionics systems will fly on FLTA007 and operate in “shadow mode”; that is, the new avionics will operate in the background but not control the flight.

Block II will also use improved thermal protection that will be tested aboard “Stairway to Seven.” Including Block II hardware on FLTA007 will help qualify some improvements and gain flight heritage for systems before Block II debuts on the next flight.

Alpha Block II will feature longer first and second stages with stronger carbon-composite structures manufactured using automated methods. The new version will also use optimized first and second stage propellant tank configurations to extend burn time. Block II will still use four Reaver engines on the first stage and one Lightning engine on the second stage.

Graphic comparing Alpha Block I and Block II. (Credit: Firefly Aerospace)

Should “Stairway to Seven” be a success, the first Block II flight will be the US Space Force’s VICTUS HAZE Jackal mission, which is scheduled for no earlier than the second quarter of this year. The National Oceanic and Atmospheric Administration’s (NOAA) QuickSounder mission is also on the Alpha manifest for this year, and other missions may also fly before the end of 2026.

Alpha, capable of flying over 1,000 kg to LEO, or over 600 kg to a 500 km high Sun-synchronous orbit, currently flies out of VSFB SLC-2W. Firefly, while developing its Eclipse medium-lift launch vehicle, also plans to fly Alpha missions from Launch Pad-0A at Wallops Island, Virginia, and from the Esrange Space Center in Kiruna, Sweden.

NASASpaceflight is providing launch livestream production services for Firefly FLTA007.

(Lead image: Alpha on the pad at SLC-2W. Credit: Firefly Aerospace)

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