Gilmour Space Technologies

[FutureSpaceTourist]

https://twitter.com/gilmourspace/status/1587974992763191296

Our new #Juru designed ‘mission patch’ for the Bowen Orbital Spaceport 💯 describes our mission… ‘Bridging Country to Sky’!

Thanks to Robert Paul for this beautiful representation of Gilmour Space’s journey to the stars…now up on our Vehicle Assembly Building at the #BOS! 🚀

[plugger.lockett]

Is this normal for ~40 seconds into the burn?

[edzieba]

Looks like a chunk of the propellant grain broke loose.

[Norman]

I've got a sneaking suspicion that this was an early or unexpected failure of the engine as well, despite what Gilmour's claiming:

- They state this motor will be used for both first and second stages of the Eris launch vehicle
- Their own website (https://www.gspacetech.com/launch, scroll down to trajectory image) states that both of the first two stages burn for ~100s (probably around 90-95s to allow for stage sep and fuel core heating)
- This latest video shows 1 min 28 s (88s) elapsing between stable combustion being achieved and first visible signs of failure (a small flame appears at the bottom of the exhaust a few seconds before the catastrophic failure)

That's not a lot of margin, unless they were running the engine at very extreme conditions as part of the qualification campaign.

Running a motor to the point of failure intentionally is also a strange approach to testing. If it was done intentionally as is being claimed, to me that says the launch vehicle is underperforming and they're trying to squeeze every single last ounce of performance out of it - they have to find the upper limit and run as close to that as possible. If they have a set of requirements to work to instead, you would test to those + some margin of safety. Running to failure in that case unnecessarily risks damaging your test stand, and means you don't have as good insight into how the motor was affected by running within the qualification limits (because it's now in pieces).

Either they did test to failure intentionally, and they don't have the performance they need, or the failure was unexpected/early. Or the Prop team/company leadership isn't doing a great job...

[edzieba]

Third possibility: Nominal flight firing profile includes throttling (it's a hybrid, you can do that), but this test firing was a harsher constant-max-throttle firing to failure or oxidiser depletion.

[CameronD]

Is it significant that (unlike RocketLab, etc.) both Gilmour and ATSpace are planning to use hybrid rocket motors??

[plugger.lockett]

I don't think so but to answer that question will require one of them to successfully fly a rocket and make orbit.

[trimeta]

Is it significant that (unlike RocketLab, etc.) both Gilmour and ATSpace are planning to use hybrid rocket motors??

Gilmour and TiSpace are among a handful of companies which argue that hybrid motors are easier to develop than liquid engines, while retaining all the key benefits: others in this group include Innospace (South Korea), HyImpulse (Germany), Vaya Space (US), bluShift Aerospace (US), Reaction Dynamics (Canada), Equatorial Space Systems (Singapore), and ARRC (Taiwan). Whether you buy their argument that it's safer, more environmentally friendly, and more reliable than traditional motors and engines (as opposed to these companies not having the technical sophistication to build liquid engines, nor the weapons-grade licensing to build solid motors) is up to you.

[Steven Pietrobon]

Running a motor to the point of failure intentionally is also a strange approach to testing.

Testing to failure is not strange. NASA did the same thing for the SLS hydrogen tank. It tells you if you correctly calculated the margin for your design. Here's the moment of failure, which looks to be at the nozzle throat.

Their own website (https://www.gspacetech.com/launch, scroll down to trajectory image) states that both of the first two stages burn for ~100s (probably around 90-95s to allow for stage sep and fuel core heating). This latest video shows 1 min 28 s (88s) elapsing between stable combustion being achieved and first visible signs of failure (a small flame appears at the bottom of the exhaust a few seconds before the catastrophic failure)

I calculate 94 seconds from the time of ignition to the failure, which is still less than the 100 s burn time given in the website for the second stage. A previous test had a burn time of 82 seconds, so this test was 12 seconds longer, for a margin of 15%. I suspect the burn duration given in the website is incorrect.

[FutureSpaceTourist]

https://twitter.com/gilmourspace/status/1595303072573837315

And hot on the heels of our #Sirius qualification test… our team is happy to announce that #Phoenix, our third stage engine, is now ready for #TestFlight1"!

Phoenix is our #3Dprinted liquid rocket engine that will be delivering payloads to orbit. #behindthescenes  🚀🚀

[CameronD]

It'll be interesting to see how they manage the paperwork, but here's hoping they have better luck than ATSpace has had to date:

The Eris rocket developed by Australian company Gilmour Space will be the first Australian system to go into orbit if it successfully launches next year,
Australian company Gilmour Space has nearly finished building a rocket that it will attempt to launch into space in April 2023. If successful, it will be Australia’s first homegrown orbital spacecraft.

The rocket, called Eris, will stand 23 metres tall and weigh over 30 tonnes. It will be powered by five hybrid engines that contain a solid fuel and a liquid oxidiser.

A final test conducted in early November found that each engine could generate 115 kilonewtons of thrust – “enough to pick up three or four SUVs [sports utility vehicles] each”, says Gilmour.

The company expects to finish building Eris by March and is planning a test launch from a site near Bowen in north Queensland in April.

The rocket will be fitted with a lightweight satellite and aim to enter low Earth orbit.

https://www.newscientist.com/article/2347513-australias-first-rocket-is-set-to-launch-into-space-in-april-2023/

[FutureSpaceTourist]

https://twitter.com/gilmouradam/status/1606034035116978176

The best birthday present I’ve ever had. I can’t wait to launch this into space next year.

[FutureSpaceTourist]

https://twitter.com/infographictony/status/1611146350921658368

So excited, @GilmourSpace just released their official mission patch for Test Flight 1. It was a team effort in its design phase. Can’t wait to share more of what we might collaborated on in the future. Go TeamGilmour.

[Jermine1269]

this is cool! their HQ is in my hometown!  I'll definitely have to check them out!

[PM3]

The Eris rocket developed by Australian company Gilmour Space will be the first Australian system to go into orbit if it successfully launches next year,
Australian company Gilmour Space has nearly finished building a rocket that it will attempt to launch into space in April 2023. If successful, it will be Australia’s first homegrown orbital spacecraft.

Are they really aiming for orbit on this first launch? Is there some publication by Gilmour which says "orbital"? There could be some misunderstanding of a suborbital test of an "orbital rocket".

Btw, in late 2021 Gilmour said they will launch by mid 2022. In late 2022 they say launch in April 2023. This converges to a launch in 2024 ...

[plugger.lockett]

The Eris rocket developed by Australian company Gilmour Space will be the first Australian system to go into orbit if it successfully launches next year,
Australian company Gilmour Space has nearly finished building a rocket that it will attempt to launch into space in April 2023. If successful, it will be Australia’s first homegrown orbital spacecraft.

Are they really aiming for orbit on this first launch? Is there some publication by Gilmour which says "orbital"? There could be some misunderstanding of a suborbital test of an "orbital rocket".

Btw, in late 2021 Gilmour said they will launch by mid 2022. In late 2022 they say launch in April 2023. This converges to a launch in 2024 ...

Apparently, straight to orbit. I kinda hoped they'd at least test fire the first stage in the 4 engine config they plan to fly it on. But that doesn't seem to be on the cards.
Hopefully they'll at least conduct a wet dress this time. 

[Zed_Noir]

The Eris rocket developed by Australian company Gilmour Space will be the first Australian system to go into orbit if it successfully launches next year,
Australian company Gilmour Space has nearly finished building a rocket that it will attempt to launch into space in April 2023. If successful, it will be Australia’s first homegrown orbital spacecraft.

Are they really aiming for orbit on this first launch? Is there some publication by Gilmour which says "orbital"? There could be some misunderstanding of a suborbital test of an "orbital rocket".

Btw, in late 2021 Gilmour said they will launch by mid 2022. In late 2022 they say launch in April 2023. This converges to a launch in 2024 ...

Apparently, straight to orbit. I kinda hoped they'd at least test fire the first stage in the 4 engine config they plan to fly it on. But that doesn't seem to be on the cards.
Hopefully they'll at least conduct a wet dress this time. 

Ahem. You don't test fire a hybrid engine like in a static fire for liquid engines. Every time a hybrid engine burns the solid propellant with its structural casing part have to be replaced.

Don't know if a wet dress rehearsal for large hybrid engines is practical or desirable.

[CameronD]

Don't know if a wet dress rehearsal for large hybrid engines is practical or desirable.

Since no-one has done this before, that's a reasonable question.  If ATSpace's recent attempts are anything to go by, it seems  a WDR using some form of inert pressurised gas (GN2?) is, at very least, a good idea.

[plugger.lockett]

The Eris rocket developed by Australian company Gilmour Space will be the first Australian system to go into orbit if it successfully launches next year,
Australian company Gilmour Space has nearly finished building a rocket that it will attempt to launch into space in April 2023. If successful, it will be Australia’s first homegrown orbital spacecraft.

Are they really aiming for orbit on this first launch? Is there some publication by Gilmour which says "orbital"? There could be some misunderstanding of a suborbital test of an "orbital rocket".

Btw, in late 2021 Gilmour said they will launch by mid 2022. In late 2022 they say launch in April 2023. This converges to a launch in 2024 ...

Apparently, straight to orbit. I kinda hoped they'd at least test fire the first stage in the 4 engine config they plan to fly it on. But that doesn't seem to be on the cards.
Hopefully they'll at least conduct a wet dress this time. 

Ahem. You don't test fire a hybrid engine like in a static fire for liquid engines. Every time a hybrid engine burns the solid propellant with its structural casing part have to be replaced.

Don't know if a wet dress rehearsal for large hybrid engines is practical or desirable.

Uh, you seem to be conflating my hopes for test firing their planned 4 engine config with my hopes they'll also conduct a wet dress to see if something lets go like their unintentionally funny first 'test launch'. Also, they've done numerous single engine static fires, as seen in this thread. I don't think it's out of the realm of expectation that they'd attempt to fire 4 in the never tested first stage config they're planning to use before attempting to fly the thing for real.

If you can't load and unload your oxidiser in a hybrid motor (you know, a wet dress rehearsal) you probably shouldn't fly the thing. And I don't know why the hybrid being large would matter, other than most that have played with large hybrids enough have been bit by them.

[Zed_Noir]

<snip>
And I don't know why the hybrid being large would matter, other than most that have played with large hybrids enough have been bit by them.

The structural integrity of the solid propellant grain after either an oxidizer or something inert flows through at operational engine pressure level in a large hybrid engine hasn't been tested much.

Big chunks of the grain breaking off might obstruct the engine exhaust flow and cause an over pressure event inside the engine casing, if the propellant grain structural  integrity fails after a previous oxidizer or inert substance flow through a large hybrid  engine.