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Firefly first launch attempt fails after liftoff, shortly before stage separation

Alpha rocket exploding
Screen capture from Everyday Astronaut live stream.

Capitalism in space: Firefly’s first attempt to launch its Alpha rocket to orbit failed at T+2:30 minutes, shortly after it went supersonic and just before first stage engine cut-off and stage separation.

The screen capture to the right shows that explosion.

Lift-off procedures went very well, though the rocket itself appeared to reach supersonic speeds later than their timeline predicted, suggesting it was underpowered.

In fact, the whole operation reminded me of SpaceX’s early attempts to launch its Falcon-1 rocket. Just as happened in one of those early SpaceX launches, there was a launch abort at liftoff, the launch team quickly figured out what happened, recycled the rocket, and successfully lifted off an hour later. Kudos to that team!

The failure is unfortunate, but to repeat the cliche, this is rocket science. They will try again.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

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  • Joe

    It is unfortunate but they will try again. I had a satellite onboard. Her name was Serenity and she was built for Teachers in Space. It was a lot of hard work that gave me insight into building satellites.

    So, Serenity II is already under construction. It will be much improved over the last design.

  • Col Beausabre

    One thing I noted is that shortly after reaching supersonic speed, they were expected to encounter MaxQ. It’s obviously very early, but I wonder if the rocket didn’t physically fail due to the dynamic pressure. And yes, I noticed that it seemed underpowered as well.

  • Questioner

    Again a flight with clearly too little thrust, but not from the start, otherwise the rocket would not have accelerated as quickly in the beginning. Normally this rocket should have reached Mach 1 after a little more than a minute of flight time and not after 2 minutes and 20 seconds, a point in time that was no longer very far from cut-off, which could be expected perhaps 30 seconds later. I would already expect a speed of Mach 3 to 4 for this point in time (2 min 20 s). If one of the four engines failed, why didn’t the Range Safety Officer detonate the rocket sooner?

  • Questioner

    I took a closer look at the recording of the flight at “Everydayastronaut”, namely a view from the rocket onto its own engine jet or plume. After that, it seems to me clear to be the case from about 1 minute 30 seconds onwards that massive unburned propellant in form of drops was released on the left side, indicating that at least one of the engines has failed.

  • Questioner … After that, it seems to me clear to be the case from about 1 minute 30 seconds onwards that massive unburned propellant in form of drops was released on the left side, indicating that at least one of the engines has failed.

    Interesting observation … the booster “dropped a hole”, as they say in drag racing when the ignition process fails in one cylinder and unburned fuel is blown out its exhaust header.

  • Chris

    Would a technique of lower power/lower speed and acceleration in the initial stages of launch where the atmosphere is thicker and then a full power higher speed and acceleration in the higher less dense atmosphere be applicable or practical?
    This would change the mechanics of course (I think) and a Max Q would still need to be overcome. However would this Max Q be slightly less due to thinned atmosphere?
    This would also complicate the engine and control system design I assume.

  • Joe


    You run into the problem of moving that mass at a slower flight profile. A rocket needs to get to through the atmosphere as quickly as possible as aerodynamic drag is killer. Subsonic and transonic profiles generally suck for big rockets. Hence the ‘get off the pad fast’ method.

    Get up, get out, and get going.

  • Calvin Dodge


    You also have the issue of gravity loss. A lower thrust setting means more of the fuel is wasted countering gravity. I believe this is why Elon is cramming so many engines into Super Heavy, as well as increasing the thrust per engine at the expense of a little ISP

  • “dropped a hole”
    I’m pretty sure that when one includes jargon/terms-of-the-art, English has a word or phrase for everything. Really? That’s enough of a “thing” that there is an expression for it?

    It’s not even 0800 (local) and I can already call it a day, having learnt my new thing.

  • markedup2 … “dropping a hole”/”dropping a cylinder” is very common in the classes of drag racing where nitromethane is used for fuel (Top Fuel, Fuel Funny Car).

    To get the thousands of horsepower (for a few seconds) you need to be competitive, massive amounts of fuel are injected … sometimes to the point of flooding the cylinder and suppressing ignition, if the crew chief has set up the car less than perfectly. Or, the dual-plug-per-cylinder/dual-magneto ignition system malfunctions and creates the same result. It is characterized by the replacement of the usual flame blasting from the cylinder’s exhaust header with white vapor.

    One of the effects of this malfunction, ironically, is asymmetrical thrust from the headers of the V-8 engines used … dropping a hole has the effect of pushing the car towards the direction of the malfunctioning cylinder, which combined with the loss of power usually leads to the loss of the race as the driver frantically tries to keep the car from crossing into the other lane, or hitting the outer wall.

    That is, when it doesn’t lead to a backfire that can literally blow the supercharger off the top of the engine.

    Drag racing can be compared to two hunters being chased by a bear … to win, you don’t have to be able to outrun the bear – only the other hunter. A lot of upset wins in the nitro-fueled classes are the result of the favored car/driver undergoing malfunctions like this.

  • Questioner

    The rocket lost most of its acceleration a short time (15 seconds?) after launch, as this video clearly shows. That is, the engine problem started as early as this. I can also see a sudden change in the rocket’s plume at this moment.

  • Col Beausabre

    Here’s a report as of Saturday Sept 4

    “The rocket, which launched from Vandenberg Space Force Base north of Los Angeles on Thursday, appeared to have a smooth liftoff as it soared out over the Pacific Ocean and approached supersonic speeds. But then, the rocket began to cartwheel, turning over itself, before US Space Force officials on the ground directed the company to destroy the rocket mid-air — called an emergency abort — so that it would not tumble uncontrolled back toward people or property. ”

    I have to watch the video again to see if I can detect the tumbling

  • wayne

    Your question has come up before, but I have no idea in what thread the best answers are.
    (apparently, there is no super-graceful way to do this.)

    “SpaceX Launch with a Monster Truck Announcer”

  • Edward

    Questioner asked: “If one of the four engines failed, why didn’t the Range Safety Officer detonate the rocket sooner?

    A failed engine is not a range safety issue. Going off course is. If the flight is terminated too soon then valuable data will not be collected, and some of that data may be able to help determine the problem or its cause. Until it becomes a safety issue, then there is no need to terminate there flight.

    There have been cases in which a failed engine still resulted in a successful launch to orbit, although not necessarily the desired orbit. These cases usually are when the failure is late in the stage’s burn.

    Joe wrote: “It is unfortunate but they will try again. I had a satellite onboard. Her name was Serenity and she was built for Teachers in Space.

    This is disappointing news. I have been waiting for two or three years to hear your report on the results of your satellite. I hope the next one makes it to orbit soon. That was a well chosen name.

  • Jester Naybor:

    Thank you for the concise explanation of ‘dropping a hole’. I like drag racing, and Top Fuel V-8’s put out locomotive power. And yes, it’s a common occurrence at the bleeding edge of internal combustion, and a big reason drag racing is fun to watch. Will the car survive?

  • Questioner

    Edward: It was already clear after about 30 seconds of flight time (loss of thrust started about 15 seconds after the start of the mission), due to the very slow ascent rate of the rocket, that the mission could not be saved by a longer burn time due to the very high gravitational losses. The mission was failed.

    The question arises as to what is the optimal altitude to end the flight of the missile and detonate it, taking into account the minimization of the dangers on the ground from impacting debris. This time some debris has hit near inhabited areas.

  • Edward

    The attempt to get to orbit was my second point in a general answer. I tried to point out that it was not a consideration in this case by saying that it is usually later failures that make it to space.

    In this case, the question was not one of where the debris would fall, because the rocket lost control and was pointing itself in seemingly random directions. At that point the range safety officer is highly likely to end the flight right then, as the rocket could send itself toward inhabited areas and cause real damage.

    For this reason, range safety is a serious issue. Disasters can and have occurred, from the Nedelin catastrophe in 1960 to the Long March 3 that crashed into a village seconds after lift off in 1996. (3 minutes)

    There are reasons to terminate sooner rather than later and reasons to terminate later rather than sooner. Choosing correctly is why the range safety officer earns his space bucks.

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