Skyrora

[john smith 19]

Here a capture of the vehicle on the pad.

I think what's really interesting is their operations. There is literally nothing there that they didn't bring with them. No concrete slabs or anything. Just basically 4 shipping containers with the whole "range" and control operation.

That's about as bare as you can get. Impressive.

[edzieba]

Why do they keep saying launch ATTEMPT. It was a successful launch (vehicle flew up and left pad), the mission was a failure.

No launch provider on the planet would declare a launch complete as soon as the vehicle lifts off of the holddowns. 'Launch' covers more than just liftoff.

[Steven Pietrobon]

That was very strange. When the vehicle lifts of the pad, there is no visible exhaust, which then appears and disappears several times!

[lrk]

It burns HTP/RP-1.  The HTP may not have been decomposing efficiently enough/at a sufficient temperature to maintain stable ignition of the RP-1 injected into the hot steam/O2.

[Kryten]

 New video. They are improving, but it's going from 'no launch footage' to 'almost no launch footage'.

[FutureSpaceTourist]

https://www.skyrora.com/skyroras-response-to-the-skylark-l-anomaly/

SKYRORA’S RESPONSE TO THE SKYLARK L ANOMALY

Skyrora recently conducted the first test launch of our suborbital Skylark L vehicle from the northeast of Iceland. After leaving the launch pad, an anomaly cut the vehicle’s maiden flight short, and it landed safely in the Norwegian Sea approximately 500 metres away from the launch site.

Following a thorough investigation into the root cause by our team of specialists, it was concluded that all mechanical systems aboard the vehicle were nominal, and that the anomaly was ultimately caused by a software complication.

The team will use the valuable data collected through the test launch to resolve this issue ahead of future launches. We would like to thank our local partners for their assistance in the recovery operations.

[Steven Pietrobon]

Did someone forget a hyphen in the software?

https://www.wired.com/2009/07/dayintech-0722/

[FutureSpaceTourist]

https://twitter.com/skyrora_ltd/status/1599690192570515463

It's been nearly two months since #Skyrora conducted the test launch of #SkylarkL from Iceland, a critical step forward in our journey to reach orbit. 🚀

Check out an extended video of the launch process produced with our friends at @TotalSpaceNet  👇

loom.ly/U8x-x6U

[john smith 19]

https://twitter.com/skyrora_ltd/status/1599690192570515463

It's been nearly two months since #Skyrora conducted the test launch of #SkylarkL from Iceland, a critical step forward in our journey to reach orbit. 🚀

Check out an extended video of the launch process produced with our friends at @TotalSpaceNet  👇

That is a very bare launch site. 

Basically it's a field by the sea.

And they put a complete launch site there, then took it down again, which is very tidy.

True it didn't go more than 500m but it got off the pad and didn't destroy any of the launch hardware. Presumably they got a fair bit of telementry back and will feed the results back into skylark and their other projects. Without the uncommanded engine shut-down there's no reason to think they wouldn't have gone all the way.

There next flight should be interesting.

[Steven Pietrobon]

Engine specs from the video.

[john smith 19]

Engine specs from the video.

I'm no expert those figures don't look too shabby for a pressure fed HTP at sea level conditions.

Or is that just my ignorance talking?

The other question I'd ask is "What's the T:W ratio?" While 3d printing does (in principal) allow you to eliminate joints and "unitise" lots of stuff I've always been a bit wary of the quality of the material laid down.

Just my $0.02.

[Steven Pietrobon]

I'm no expert those figures don't look too shabby for a pressure fed HTP at sea level conditions.

Or is that just my ignorance talking?

That is not an ignorant conclusion. In comparison, the old pump fed British Gamma HTP/Kero engine used on Black Knight and Black Arrow had a sea level Isp of 2108 m/s (215 s) and vaccum Isp of 2450 m/s (250 s), so they are getting quite good performance considering the propellants being used.

[john smith 19]

I'm no expert those figures don't look too shabby for a pressure fed HTP at sea level conditions.

Or is that just my ignorance talking?

That is not an ignorant conclusion. In comparison, the old pump fed British Gamma HTP/Kero engine used on Black Knight and Black Arrow had a sea level Isp of 2108 m/s (215 s) and vaccum Isp of 2450 m/s (250 s), so they are getting quite good performance considering the propellants being used.

Wow. You're saying they are exceeding a pumped engine Isp with just pressure feed?

I knew the Gamma (indeed the whole Black Arrow programme) was built on a (tight) budget but I'd always thought they were pretty near the limit of the theoretical performance for this propellant combo.

My appreciation for Skyrora's execution skills just went up a notch.
[EDIT I'm starting to quite like this team ]

[briantipton]

I'm no expert those figures don't look too shabby for a pressure fed HTP at sea level conditions.

Or is that just my ignorance talking?

That is not an ignorant conclusion. In comparison, the old pump fed British Gamma HTP/Kero engine used on Black Knight and Black Arrow had a sea level Isp of 2108 m/s (215 s) and vaccum Isp of 2450 m/s (250 s), so they are getting quite good performance considering the propellants being used.

Steve, I hesitate to question you on anything related to HTP/Kero as you are something of an expert, but I have seen higher Isp quoted for the Gamma 8. Encyclopedia Astronautica has 251 and 265 for SL and Vac respectively, and these would seem more aligned with the theoretical Isp relative to Keralox. These numbers would also suggest Skyrora's performance is about what one would expect from a pressure fed engine.

[Steven Pietrobon]

Steve, I hesitate to question you on anything related to HTP/Kero as you are something of an expert, but I have seen higher Isp quoted for the Gamma 8. Encyclopedia Astronautica has 251 and 265 for SL and Vac respectively, and these would seem more aligned with the theoretical Isp relative to Kerolox.

Its always good to question the experts! They are human and make mistakes as well. I checked Encyclopedia Astronautica and they give their references as

[1] Kudryavtseva, V M, ed., Zhidkostnikh Raketnikh Dvigatley, Visshaya Shkola, Moscow, 1993. Russian-language textbook on rocket theory.
[2] Wikipedia Article: http://en.wikipedia.org/wiki/Gamma 8

My reference is

D. Andrews and H. Sunley, "The Gamma rocket engines for Black Knight," J. of the British Interplanetary Society, vol. 43, pp. 301-310, July 1990.

"My not-very-reliable memory suggests that the specific impulse at sea level was about 2108 m/s, rising to about 2450 m/s in vacuo."

I didn't realise that these values were from memory, which is notoriously unreliable! I found a second source though which confirms these values. From

H. G. R. Robinson, "The genesis of Black Arrow," J. of the British Interplanetary Society, vol. 45, pp. 149-154, Apr. 1992.

gives the Black Arrow first stage Isp as 218 s (2138 m/s sea level) and 250 s (2452 m/s, vacuum). The second stage had an Isp of 270 s (2648 m/s).

[Steven Pietrobon]

Wow. You're saying they are exceeding a pumped engine Isp with just pressure feed?

That is what Skyrora seem to be showing. The Gamma Mk.301 had a chamber pressure of only 4.14 MPa and used an open cycle gas generator (decomposing HTP into steam and GO2). Not sure what the Skylark L chamber pressure is, but being pressure fed means that there is no Isp loss from the gas generator.

I knew the Gamma (indeed the whole Black Arrow programme) was built on a (tight) budget but I'd always thought they were pretty near the limit of the theoretical performance for this propellant combo.

The Gamma engine was no where near what HTP/Kero can perform. The Skyrora XL launch vehicles uses staged combustion HTP/Kero engines on the first and second stage. That achieves an Isp of 250.24 s (2454 m/s) at sea level and 284.91 s (2794 m/s) in vacuum. The second stage has an Isp of 306 s (3001) m/s.

https://www.skyrora.com/skyrora-xl/
https://www.skyrora.com/wp-content/uploads/2022/01/payload-user-guide-october-2019.pdf

"The Skyforce is a unique staged combustion engine which runs on Hydrogen Peroxide and Kerosene. A closed cycle allows the engine to be throttled over a wide range and increase the specific impulse, without over-engineering of the design."

If using SSME chamber pressure of 20.7 MPa, 77.5:1 expansion ratio and 97.4% efficiency I get a vacuum Isp of 3223 m/s (328.7 s).

[john smith 19]

The Gamma engine was no where near what HTP/Kero can perform. The Skyrora XL launch vehicles uses staged combustion HTP/Kero engines on the first and second stage. That achieves an Isp of 250.24 s (2454 m/s) at sea level and 284.91 s (2794 m/s) in vacuum. The second stage has an Isp of 306 s (3001) m/s.

You're right those figures beat the Gamma hands down, although they suggest the Pch is not up to the sky-high levels of the SSME. I hadn't thought you could do that good with this combo, although I'd never actually run ISP to find out.

I remember someone (I think it was HMX) mentioning the Gamma's were built to a price and part of that was using a cast aluminum gearbox, which had a casting factor of something over 1.7. IE it 1.7x heavier than a wrought design. This had a significant effect on the T/W ratio.

It's important to remember that without the Waxwing solid as the third stage Black Arrow would never have put a payload in orbit.

[FutureSpaceTourist]

https://twitter.com/skyrora_ltd/status/1604763652598415361

Our Quarter 4 newsletter is officially here! 🚀

#Skyrora has taken a significant step towards the launch of #SkyroraXL with a suborbital launch attempt this quarter, and we look forward to continuing on this trajectory in 2023!

Read more: https://www.skyrora.com/quarter-4-2022-in-review/

[Steven Pietrobon]

Our Quarter 4 newsletter is officially here! 🚀

#Skyrora has taken a significant step towards the launch of #SkyroraXL with a suborbital launch attempt this quarter, and we look forward to continuing on this trajectory in 2023!

Read more: https://www.skyrora.com/quarter-4-2022-in-review/

Launch of Skylark L was on 8 October. More Skylark L launches are planned with the orbital Skyrora XL launch planned for the end of 2023.

"Skyrora was thrilled to conduct a launch attempt of our suborbital Skylark L vehicle into space from Langanes, Iceland on 8th October 2022 to test critical processes and components ahead of a full orbital launch from the UK at the end of 2023.

After leaving the launch pad, a software-related anomaly cut the maiden flight short, with the vehicle landing in the Norwegian Sea approximately 500 meters away from the launch site. No harm was caused to people or wildlife in any way."
...
"As Skyrora approaches orbital launch at the end of 2023, the demonstrator launch of Skylark L enabled the team to test 70% of the technology which will be applied to the systems of the Skyrora XL vehicle, providing a key incremental learning opportunity to increase technological readiness.

The team is already preparing for future launches of Skylark L to establish the launch heritage key to reaching orbit."

[moontomars]

Some more numbers for Skyrora. Haven't seen it mentioned, but they're charging GBP 30,000 per kg of payload for their Skyrora XL.

Another thing that I'm starting to wonder: They're going for a launch cadence of 16 per year (let's say in 2030). Orbex says 10-12 are fine in 2030 according to their latest podcast with EuropeanSpaceflight. RFA has just announced exclusive use of a pad at SaxaVord, who can support a maximum of 30 launches per year. Andoya has leased a pad exclusively to Isar, so there are only 10 launch slots per year left (maybe 20 if they build their third pad).

Where are these companies supposed to launch from? Has anyone taken a closer look at the validity of Skyrora's mobile launch complex? This is from their 2019 XL payload guide:

Numbers indicating: assembly facilities for integration (1) testing, rocket propellant infrastructure (2) including storage (3), filling systems (8, 9), a mission control centre (5), power supplies (6) and launch pad (11) and emergency infrastructure (13, 14).

I should mention that Skyrora has signed MoUs(“Memorandum of Understanding”) with Maritimes Launch Inc. in Novia Scotia, Canada, as well as the German Offshore Spaceport Alliance (GOSA) for a mobile launch platform in the North Sea in Germany. The latter is definitely still in the ideation phase, Maritimes Launch Inc. has apparently started construction according to their website.