Author Topic: Orbital Access  (Read 6215 times)

Offline ringsider

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Orbital Access
« on: 11/18/2016 10:30 AM »
According to this filing (PDF):

https://beta.companieshouse.gov.uk/company/SC512473/filing-history/MzE1NzI1Nzg1MmFkaXF6a2N4/document?format=pdf&download=0

Orbital Access sold 29 shares (22% of the firm) at a price of GBP 59,183 each in August 2016, raising about 2m EURO. [SEE AMENDMENT BELOW]The purchaser is an Edmund Arcadian.

Website: http://www.orbital-access.com/

It looks like an air launch system with some connection to the UK's Skylon / SABRE project.

Video of CEO:

« Last Edit: 03/20/2017 09:29 AM by ringsider »

Offline knowles2

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Re: Orbital Access
« Reply #1 on: 11/18/2016 07:43 PM »
Good they raise money.

Having done a bit of research (cyber stalking the bloke)Edmund Robert Charles Grech Arcadian, not much to go on his facebook page, https://www.facebook.com/edmundarc,

he also connected to
VALON LIMITED https://beta.companieshouse.gov.uk/company/10038764
The company has no website or any other online presence. But the company is control by Active Management International Ltd, https://beta.companieshouse.gov.uk/company/10038764/persons-with-significant-control
An they do have a website, just not a very detail one here, http://activemgr.com/  they seem to have work with Nasa in the past.

Edmund also run ARCADIAN ENTERPRISES LTD

https://beta.companieshouse.gov.uk/company/04379754
Again not web presence :(

The good news is Edmund seem at least be interested in flying space ships at least the virtual kind, having an account on the Star citizen forum https://robertsspaceindustries.com/citizens/Paradigm

So there not a lot about this guy on the web.

Still not clear whether their goal is the development of Prestwick into a spaceport or to develop a vehicle for launching satellites into orbit with the hopes of eventually developing a craft that uses Sabre engines or perhaps they want to do both. 

The companies listed in the post are companies that people who are interested in Sabre, skylon should keep an eye on in imho.

Offline ringsider

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Re: Orbital Access
« Reply #2 on: 03/19/2017 06:46 PM »
I just noticed another filing by this company, that relates to the same time period as the first one above, but it was only filed 6 weeks ago.

The new one indicates they made an error in their first filing.

goo.gl/YQDRLP

This new one says that on 8.30.2016 they sold 108 shares at a total value of GBP 220,416.00, which works out at GBP 2,040 per share.

But in the original filing on 8.8.2016 they stated they had sold 29 shares for GBP 59,183.78 per share:

goo.gl/hqiI8m

Based on the second filing however, this isn't right - and if you divide 59,183.78 by 29 you get to the same share price as the new filing, GBP 2040.

In fact there is almost no rational way they could have sold 29 shares at almost GBP 60K a share and then turned around 3 weeks later and sold the same shares for 30 times less - no existing shareholder would allow that. They are all the same share class.

So it looks like they actually only raised about GBP 280K in August, not EUR 2,000,000... and sold about 57% of the company for that amount. And we are now 7 months later, so I wonder how much is left?

They did win a study for GBP 250K last spring, with several other partners, but I imagine that a) not all that amount is theirs simply because there are partners, and b) it is probably gone by now. This is the paper they put out about the project late last year; they are proposing to build an airlaunch orbital launcher based on SABRE / Skylon from a DC10 that will fly by 2020:-

goo.gl/AE89fo

goo.gl/PsmaHg
« Last Edit: 03/19/2017 07:11 PM by ringsider »

Offline WmThomas

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Re: Orbital Access
« Reply #3 on: 03/19/2017 10:00 PM »
A couple hundred thousand pounds? That's chicken feed.

They're not going anywhere if that's their capitalization.

Even two million would be a bare starter for an attempt to create a launch system.

Two hundred million, brilliance, and tons of elbow grease might, must might, get it done.

Offline ringsider

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Re: Orbital Access
« Reply #4 on: 05/04/2017 08:06 PM »
Orbital Access seeks listing lift for space ambitions

Bid to develop commercial facilities as part of competition for space port by 2020
 
MAY 1, 2017

A Scottish start-up that is bidding to send satellites into orbit from the UK with a reusable rocket launcher is aiming to raise €5m through a listing on Malta’s new junior market.

Orbital Access on Friday submitted its bid to develop commercial satellite launch facilities at Prestwick and Newquay airfields as part of a government competition to have an operational space port by 2020.

The company, created by the grandson of Prestwick airport’s founder, is applying to Malta’s Prospects exchange for a listing that would give it access to debt and equity funding to develop its Orbital 500R aircraft.

This will be an adapted widebody aircraft, which will carry a small payload rocket to be launched at altitude.

The group, which last year secured £250,000 in UK government funding for the concept, is also hoping that its vehicle will be the test platform for the Sabre engine being developed by Reaction Engines.
.
.
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Over the next few years, Orbital Access is hoping to progress to a main market listing, where it aims to raise up to €300m in debt and equity funding to match expected UK and European Space Agency grants to develop its horizontal launch system.

Full article, much more detail:-

https://www.ft.com/content/a9d0600a-2dfa-11e7-9555-23ef563ecf9a
« Last Edit: 05/15/2017 06:21 AM by ringsider »

Offline Alpha_Centauri

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Re: Orbital Access
« Reply #5 on: 07/06/2017 08:32 AM »
There doesn't appear to be a central update thread for this company and now seems as good a time as any.

https://www.spaceintelreport.com/uks-orbital-access-wins-esa-two-stage-orbit-study-contract/
Quote
UK’s Orbital Access wins ESA two-stage-to-orbit study contract
by Peter B. de Selding | Jul 5, 2017

PARIS — Orbital Access Ltd. of Britain, which is designing a small-satellite launcher that would lift off from a horizontal runway under the belly of a modified jet airliner, has won a contract from the European Space Agency (ESA) to carry the project to system definition before a preliminary design review.

The four-month contract is valued at 200,000 British pounds ($257,000). Orbital Access estimates that carrying the program through to first flight would take about four years and cost some 500 million pounds.

---

http://www.orbital-access.com/the-orbital-500/

The intent is to build a small winged reusable launcher slung from beneath a modified MD-11 capable of lofting up to 500 kg to 600 km SSO. The company is based out of Prestwick airport which has a local BAE branch involved with the maintenance and modification of aircraft.  They have also made deals with a number of other potential spaceports internationally with the ambition to launch close to the customer/desired inclination.  Despite being a small startup it has been successful in winning research grants, probably related to the connections with BAE.  The company began in part to compete for work as a result of the UK government's intent to set up a spaceport industry with a very ambitious goal of the first launch from the UK by 2020:

http://forum.nasaspaceflight.com/index.php?topic=35163.60

Perhaps the most interesting aspect of this venture is the planned synergy with Reaction Engines and the SABRE engine.  They want the Orbital 500R to be a testbed for SABRE and eventually be involved with the construction of TSTO SABRE-based launchers:

http://www.orbital-access.com/the-fspluk-project/
« Last Edit: 07/07/2017 01:00 PM by Alpha_Centauri »

Offline envy887

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Re: Orbital Access
« Reply #6 on: 07/08/2017 02:49 AM »
Is that a two-stage rocket, or are they counting the carrier aircraft as a stage?

Offline ringsider

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Re: Orbital Access
« Reply #7 on: 07/08/2017 06:08 AM »
Is that a two-stage rocket, or are they counting the carrier aircraft as a stage?

It is unclear, but I would guess the rocket part is 2STO? They say reusable so that means a chunk of it has to come back, but it's honestly not clear which part.

I like how their financial estimates in press releases keep increasing, by roughly 100 million a month:

May 1st 2017: GBP 300 million
July 5th 2017: GBP 500 million

That is very reassuring.

Plus if you read the press release, that EUR 200K grant isn't all for them: it's split across 5 parties:-

1. Orbital Access
2. BAE Systems
3. Glasgow University
4. Strathclyde University
5. ESA ESTEC

The contract covers a four-month project .... Orbital Access will work closely with BAE Systems’ whole aircraft design group at Prestwick, the high-speed aerodynamics department of Glasgow University, the Centre for Advanced Space Transportation at Strathclyde University and the high-speed aerothermodynamics team at Fluid Gravity Engineering. The European Space Research and Technology Centre (ESA ESTEC) will oversee the program.

So they picked up another EUR 50K-60K for a 4 month project? That only leaves 499,950,000 more to raise....

Offline Alpha_Centauri

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Re: Orbital Access
« Reply #8 on: 07/08/2017 09:36 AM »
Is that a two-stage rocket, or are they counting the carrier aircraft as a stage?

The winged vehicle is two-stage; the reusable winged lower stage contains a dorsal payload bay holding simple expendable upper stages, so in total three stages if you include the air-launch.

A lot more detail in this talk given by Stuart McIntyre.  Starts at 20:00 exactly;

https://www.facebook.com/rispace.conference/videos/vb.1422989437939886/1799807703591389/
« Last Edit: 07/08/2017 11:04 AM by Alpha_Centauri »

Offline john smith 19

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Re: Orbital Access
« Reply #9 on: 08/14/2017 08:39 AM »
Is that a two-stage rocket, or are they counting the carrier aircraft as a stage?
The rocket is 2 stage. You might view the aircraft as "Stage 0".

People will look at this and think it's another Pegasus but there are major differences.

Liquid fuels cut the stage count from 4 (with the last using dangerous hypergols) to 2 and should give the orbital accuracy of the 4 stage system.
Reusable engine costs can be spread across multiple flights.
In principal OA won't be beholden to one stage supplier as Orbital are with Pegasus, assuming they go with a liquid US.

There are serious challenges to the design.

Reusable TPS is unknown in the UK It would be interesting if they looked at the DLR's work with using flat sheets of RCC to create efficient hypersonic shapes that are (relatively) easy to mfg.
OA's concept plans to store propellants in the aircraft and on load just before launch, radically reducing carriage loads on the mounting for most of the trip, but it's not how missiles have been carried historically.
An internal payload bay limits the size of nozzle you can put on and the US will be operating at near vacuum levels, so bigger is always better. OTOH deploying above the atmosphere should mean you can dispense with a complex fairing (which as we know can be surprisingly expensive) and give a simple cylinder shape for payload to fit.
Another surprising factoid about Pegasus was it's wing is very strong because it goes into a 45 deg climb on separation. Which raises the question, can you get the launch aircraft closer to this attitude before drop? That's tough because at M0.8 that's a climb rate of about 53 000 ft per minute, something you'd want to maintain for seconds (at most) before you either dropped the LV or leveled off.
Assuming the US is expendable (the obvious assumption given it will be seriously volume limited) it should be as cheap as possible. This suggests as simple and OTS as possible. BLACK ARROW would be quite a good model, where the stage was spin stabilized and a fixed nozzle, with most of the guidance precision being provided by the 2nd stage. This eliminated any active hardware on the 3rd stage except the stage/payload separation mechanism. The key would be starting the US at just the right attitude and thrust termination at precisely after the right burn time, leaving the expensive high precision GNC package on the reusable booster.
In the late 60's high precision timing was bulky, heavy and expensive. Today it's a wristwatch (by the standards of the time). Sub second accurate thrust termination should be quite possible.

The real joker in the pack (IMHO) is that they are saying for $500m you can have a system that matches the most expensive per unit mass of payload to orbit system in the world.  :(

$500m with $30k/Kg is about 34 launches, assuming the whole launch price went to pay off the financing.

OTOH The first stage and carrier could act as a fully reusable sounding rocket, giving minutes of weightlessness and vacuum exposure to allow payloads to be refined before full launch. The carrier would allow deployment to other countries ranges, like the ESA one in Sweden.  This might be a more common mission, providing the prices are below that for a solid fuel SR.
« Last Edit: 08/14/2017 08:47 AM by john smith 19 »
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline JCRM

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Re: Orbital Access
« Reply #10 on: 08/14/2017 04:30 PM »
Quote
In principal OA won't be beholden to one stage supplier as Orbital are with Pegasus, assuming they go with a liquid US.
the use of different upper stages is a design goal
Quote
There are serious challenges to the design.

Reusable TPS is unknown in the UK It would be interesting if they looked at the DLR's work with using flat sheets of RCC to create efficient hypersonic shapes that are (relatively) easy to mfg.
as a suborbital vehicle the environment is less challenging, and REL have already done some work on replicating AEA's system2 and did some testing on Pyrosic. As part of the consortium they may have shared this information.
Quote
An internal payload bay limits the size of nozzle you can put on and the US will be operating at near vacuum levels, so bigger is always better.
The rectangular profile of the vehicle certainly limits the nozzle to around three quarters of the cross sectional area.
Quote
OTOH deploying above the atmosphere should mean you can dispense with a complex fairing and give a simple cylinder shape for payload to fit.
Or cuboid.
Quote
Another surprising factoid about Pegasus was it's wing is very strong because it goes into a 45 deg climb on separation. Which raises the question, can you get the launch aircraft closer to this attitude before drop?
would re-entry be more challenging than launch?
If not, with liquid engines there may be the potential to throttle them back while the vessel increases its angle of climb - simultaneously reducing the urgency of the turn and reducing the stress?
There are suggestions the carrier craft could to be used for parabolic flights as well, so may already have undergone some modifications to make a 45 degree flightpath more palatable

ETA: the study shows a far gentler flightpath, peaking at 25 degrees
Quote
The real joker in the pack (IMHO) is that they are saying for $500m you can have a system that matches the most expensive per unit mass of payload to orbit system in the world.  :(
the Rocket lab electron was 32k/kg back in 2015, I haven't seen more recent figures.
Virgin Orbit LauncherOne is $33k/kg
Admittedly they're both for smaller payloads,
Quote
$500m with $30k/Kg is about 34 launches, assuming the whole launch price went to pay off the financing.
or 21 if they achieve the grants they hope to.
Quote
OTOH The first stage and carrier could act as a fully reusable sounding rocket, giving minutes of weightlessness and vacuum exposure to allow payloads to be refined before full launch.
That appears to be something they've considered "Orbital Access intends to provide microgravity conditions on a fleet of vehicles ranging from small propeller aircraft to jet airliners to indeed the Orbital 500 itself and beyond. "
« Last Edit: 08/14/2017 04:49 PM by JCRM »

Offline john smith 19

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Re: Orbital Access
« Reply #11 on: 08/14/2017 05:52 PM »
the use of different upper stages is a design goal
As is the carriage of those propellants in the carrier aircraft.

At some point those two goals are going to come into conflict.  :(
Quote from: JCRM
as a suborbital vehicle the environment is less challenging, and REL have already done some work on replicating AEA's system2 and did some testing on Pyrosic. As part of the consortium they may have shared this information.
True, but for a commercial project time is money and a high TRL material is safer than a potentially (but not actually tested) superior material.  IIRC Pyrosic has been used in various applications and I'd love to see it tested here but if your focus is on getting a vehicle flying payloads it's the risky option.
Quote from: JCRM
The rectangular profile of the vehicle certainly limits the nozzle to around three quarters of the cross sectional area.
Shall we agree it will make the shape about equal to the profile of the payload bay (whatever that turns out to be. I think any renderings at this stage are highly provisional) , rather than having to be rounded out to fit inside a fairing?
Quote from: JCRM
would re-entry be more challenging than launch?
If not, with liquid engines there may be the potential to throttle them back while the vessel increases its angle of climb - simultaneously reducing the urgency of the turn and reducing the stress?
I'm thinking about the loads on the connection between the carrier aircraft and the vehicle.
Given that the vehicle will be 90-95% lighter on re-entry (most propellant gone. All US and payload gone)
most stresses on it should be much lower, including wing loading
Quote from: JCRM
There are suggestions the carrier craft could to be used for parabolic flights as well, so may already have undergone some modifications to make a 45 degree flightpath more palatable

ETA: the study shows a far gentler flightpath, peaking at 25 degrees
The turn would be for the landing, not the fully loaded takeoff.

Quote
The real joker in the pack (IMHO) is that they are saying for $500m you can have a system that matches the most expensive per unit mass of payload to orbit system in the world.  :(
the Rocket lab electron was 32k/kg back in 2015, I haven't seen more recent figures.
Virgin Orbit LauncherOne is $33k/kg
Admittedly they're both for smaller payloads, [/quote]
I can see the benefits to the UK economy of this happening.
I just don't really see much benefit to customers who want to put a payload into LEO.  :( :(

Quote from: JCRM
That appears to be something they've considered "Orbital Access intends to provide microgravity conditions on a fleet of vehicles ranging from small propeller aircraft to jet airliners to indeed the Orbital 500 itself and beyond. "
Without a sounding rocket that will give you 10s of secs of micrgravity at most and no vacuum exposure (unless you put a vacuum chamber inside the aircraft). Useful for paying some of the bills but it's when you can put that payload into actual space for minutes, or tens of minutes, at a time that things start to get interesting.  :(
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline john smith 19

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Re: Orbital Access
« Reply #12 on: 08/15/2017 10:22 AM »
A look at the design decisions of the Pegasus XL is also quite interesting.

The first stage rocket (S50 XL in the catalog) has no TVC and a thrust of 3x the Pegasus GTOW. Pegasus uses control surfaces on the wings to point it upward. Despite having a wing it's essentially sized for ground takeoff, with in principal a vertical acceleration of about 2g.

This stage burns out around M5.

That's interesting because the contractor who studied the USAFRL's SABRE HTO based (and ground takeoff) TSTO reckoned you needed thrust equal to 50% of GTOW [edit to get through M1]. Obviously this is a design trade question.

Previous comments by Jon Goff on a plane launched SSTO concept also suggest anything between 25-45 degrees of climb would be very useful. IIRC most airliners can do 18-25 degrees of climb comfortably, although the more the better, up to 45degs.

This is also relevant because TVC of a high thrust engine nozzle is a pretty high power system and quite specialized. If you could get away with setting the attitude through aero surfaces before it left the atmosphere, then relied on gas jets for motion outside the atmosphere for the remaining (relatively brief ?) period you would gain a significant simplification. You're going to need them anyway for getting back. Nose and wing tip jets should have significant moment arms, compared to the lever of the actuator connected to the nozzle(s). 

The downside is you have no engine TVC control authority on landing. OTOH the Shuttle had no active main engines anyway, so is that going to be a serious problem? a powered landing would be helpful but the X37b has shown it's not essential.

[EDIT An interesting question would be what drives the flying surfaces. A big block of batteries in the nose (or wherever was most convenient for the design)  could go a long way to giving the vehicle neutral trim, or whatever attitude the designers most needed it to have at the most critical stage of the flight. IRL I don't think it will be a perfect match, but I do think it would go a long way to landing the vehicle with limited control actions to keep it level. Likewise if they did go with "wet wings" splitting the tanks along the wings (front/back) and controlling which ordered they were emptied in (front/back, left/right) would also give a certain amount of control outside the atmosphere and apart from any control jets. ]

[EDIT. Data point. The Vega ELV P80 1st stage is listed as having a single string 2 axis all electric TVC which weighs 340Kg all up, to pivot a nozzle of 310 tonnes thrust over a range of +/- 5.5 Degs at 10Deg/sec overall an accumulated range of 250deg during flight. The battery pack to do this is 270V with currents in the 185-200A range. However different slides of the report I got this from disagree on capacity, one says 2.5Ahr, the other 0.6Ahr. However IIRC these are primary cells, and I'd guess a reusable system would go with secondary batteries, and presumably redundant actuators. I've no idea how to size the actuators to drive the control surfaces on a winged vehicle.  :( ]
« Last Edit: 08/21/2017 08:01 AM by john smith 19 »
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline JCRM

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Re: Orbital Access
« Reply #13 on: 08/26/2017 08:21 PM »
the use of different upper stages is a design goal
As is the carriage of those propellants in the carrier aircraft.

At some point those two goals are going to come into conflict.  :(
Having the payload fuelled as part of Skylon's launch sequence is a REL design goal. This would allow some experience of that.
Quote from: john smith 19
Quote from: JCRM
as a suborbital vehicle the environment is less challenging, and REL have already done some work on replicating AEA's system2 and did some testing on Pyrosic. As part of the consortium they may have shared this information.
True, but for a commercial project time is money and a high TRL material is safer than a potentially (but not actually tested) superior material.  IIRC Pyrosic has been used in various applications and I'd love to see it tested here but if your focus is on getting a vehicle flying payloads it's the risky option.
Using a space frame isn't common practice, but that's the approach they're taking. As I said previously I doubt they would need it for this application, but gaining flight experience might be useful for some of the consortium partners.
Quote from: john smith 19
Quote from: JCRM
The rectangular profile of the vehicle certainly limits the nozzle to around three quarters of the cross sectional area.
Shall we agree it will make the shape about equal to the profile of the payload bay (whatever that turns out to be. I think any renderings at this stage are highly provisional) , rather than having to be rounded out to fit inside a fairing?
I think the general shape is now fixed otherwise the mission analysis performed by Strathclyde would be wasted effort.
I was thinking about an array of circular nozzles, per the diagram - although that might be a two engine second stage and a one engine third stage
Quote from: john smith 19
Quote from: JCRM
would re-entry be more challenging than launch?


I'm thinking about the loads on the connection between the carrier aircraft and the vehicle.
Sorry, I though you were talking about the launch vehicle wings being strengthened, not the carrier and things just got more confused from there - my mistake.
Quote from: john smith 19
Quote from: JCRM
Quote from: john smith 19
they are saying for $500m you can have a system that matches the most expensive per unit mass of payload to orbit system in the world.  :(
the Rocket lab electron was 32k/kg back in 2015, I haven't seen more recent figures.
Virgin Orbit LauncherOne is $33k/kg
I can see the benefits to the UK economy of this happening.
I just don't really see much benefit to customers who want to put a payload into LEO.  :( :(
Their price is in the same ballpark as other proposed launchers of that class, with the advantage of a payload return for some abort scenarios, and being launched in the UK for UK customers or Malta for European ones. What are the disadvantages?

Quote from: john smith 19
Quote from: JCRM
That appears to be something they've considered "Orbital Access intends to provide microgravity conditions on a fleet of vehicles ranging from small propeller aircraft to jet airliners to indeed the Orbital 500 itself and beyond. "
Without a sounding rocket that will give you 10s of secs of micrgravity at most and no vacuum exposure (unless you put a vacuum chamber inside the aircraft). Useful for paying some of the bills but it's when you can put that payload into actual space for minutes, or tens of minutes, at a time that things start to get interesting.  :(
when used as a first stage the Orbital 500 is following a parabolic flight for 3-5 minutes. flying a 500kg payload with out an upper stage would increase that duration, replacing the upper stage with larger first stage tanks more so (but make reentry far more challenging, maybe it would need a more innovative TPS) - before I'm reminded that it can't be done because rockets aren't like Lego this vehicle is being designed as a "Lego rocket" where engines and payloads can be swapped out.

You might like to factor in that they are also talking about make the wings [act] as fuel tanks.
Where did you see that? the usage of conformal tanks I saw was for a central cylindrical Lox tank with conformal paraffin tanks either side, but within the body.

--

Given the requirement to be able to land with or without payload, I'm concerned the trim requirements might be excessive, however that big body flap might be enough

Offline john smith 19

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Re: Orbital Access
« Reply #14 on: 08/29/2017 11:31 AM »
Having the payload fuelled as part of Skylon's launch sequence is a REL design goal. This would allow some experience of that.
True. But if the first stage is LOX/RP1 how many extra lines will you plumb in for the US? And of course if you solid they are redundant. OTOH if this is to partly support REL that would mean LH2, which normally requires "Vacuum jacketed" line  :(

For civilian use in the West LOX and Peroxide are the options for oxidizer. The fuel is a bit more open. Everyone knows LH2 leads on performance but is a PITA to handle. If they are keen on lowering repeat costs the fuel cost in terms of maximum Isp per £ would be a good thing to consider, while the design is still on paper.
Quote from: JCRM
Using a space frame isn't common practice, but that's the approach they're taking. As I said previously I doubt they would need it for this application, but gaining flight experience might be useful for some of the consortium partners.

True, but it may have inherent benefits as well. While stressed skins are SOP for transport vehicles few have such a demanding temperature environment. High temperature strength quickly drops off but the structure REL plan to use (which IIRC originated from the X20 programme) lets you have a cold structure separate from a hot skin, even if the skin is not Pyrosic.

One little known fact is that NASA developed a reusable fastener design in the early 80's that could cope with securing 2 materials with wildly different (and even ansiotropic ) thermal expansion properties (like Aluminium and RCC) together.

Handy as the first stage will have to come down several Mach numbers, and unprotected Aluminium probably won't survive those conditions even briefly (although outside Beryllium it is the lightest metal) so some kind of TPS is going to be needed. 


 
Quote from: JCRM
I think the general shape is now fixed otherwise the mission analysis performed by Strathclyde would be wasted effort.
I was thinking about an array of circular nozzles, per the diagram - although that might be a two engine second stage and a one engine third stage

The details can make a significant difference. At least 1 Centaur stage was torn apart when one of the RL10 engines started and the other didn't, hence the fondness for a single big engine, rather than multiple smaller ones (not an option for the Saturn V 1st stage as the F1 was one of the biggest engines in the world already).

Obviously digital engine management units make that much less likely and much easier to abort.

Like fuel nozzle expansion ratio is one of those (relatively) cheap ways designers have to increase Isp. It would be interesting if part of REL's contribution was their E/D nozzle work. This would allow a much bigger ratio without flow separation or very high chamber pressures, but again that's a development risk.   

Quote from: JCRM
Their price is in the same ballpark as other proposed launchers of that class, with the advantage of a payload return for some abort scenarios, and being launched in the UK for UK customers or Malta for European ones. What are the disadvantages?
The problem is those other launchers are already flying or are close to being able to sell a flight, and they don't fly often at that price.
Affordable reusability is very attractive. Look at it from an investors PoV. What are their USPs?
Ready now. No
Cheaper. No
First stage reusable. Unproven.

There is not a world shortage of sounding rocket launch systems either.  :(
Quote from: JCRM
when used as a first stage the Orbital 500 is following a parabolic flight for 3-5 minutes. flying a 500kg payload with out an upper stage would increase that duration, replacing the upper stage with larger first stage tanks more so (but make reentry far more challenging, maybe it would need a more innovative TPS) - before I'm reminded that it can't be done because rockets aren't like Lego this vehicle is being designed as a "Lego rocket" where engines and payloads can be swapped out.
T3-4 minutes free flying is much more useful. Longer time is usually better in in sounding rocket work (as is lower acceleration. IIRC some of them hit a burnout acceleration of 18g). As the first stage of essentially a TSTO with starting speed of maybe M0.9, unless the first stage is going to be a very small fraction (Concorde cruised at M2.2 on an Al alloy skin) of the total needed to get to orbit a TPS is virtually certain.
Quote from: JCRM
Where did you see that? the usage of conformal tanks I saw was for a central cylindrical Lox tank with conformal paraffin tanks either side, but within the body.
I've rechecked the two reports I've seen and I've treated "conformal" as a synonym for wing tanks.   :(
My mistake.
Quote from: JCRM
Given the requirement to be able to land with or without payload, I'm concerned the trim requirements might be excessive, however that big body flap might be enough
The body flap was a key feature of the Shuttle. It protected the SSME nozzles from both the high temperature of reentry air flow but also the side forces on them, which would probably have crumpled them.   :(

Reentry vehicles have been flown with split body flap designs but I'd note the rear engines would make it very rear heavy after US/payload deployment. With the US/Payload still on board it might actually be easier to land, although venting at least one of the US propellants would probably be a good idea for safety reasons.

however sealing the airflow on control surfaces is very difficult at high temperatures. I've wondered if mounting the control surfaces on a set of end and cantilever rotary flexures would simplify the problem.
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline JCRM

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Re: Orbital Access
« Reply #15 on: 08/29/2017 06:54 PM »
I'm going to split the "how the Orbital 500 could investigate Skylon technologies" into a thread in the REL/Skylon/SABRE
Having the payload fuelled as part of Skylon's launch sequence is a REL design goal. This would allow some experience of that.
True. But if the first stage is LOX/RP1 how many extra lines will you plumb in for the US? And of course if you solid they are redundant. OTOH if this is to partly support REL that would mean LH2, which normally requires "Vacuum jacketed" line  :(

For civilian use in the West LOX and Peroxide are the options for oxidizer. The fuel is a bit more open. Everyone knows LH2 leads on performance but is a PITA to handle. If they are keen on lowering repeat costs the fuel cost in terms of maximum Isp per £ would be a good thing to consider, while the design is still on paper.
I don't know if suitable seals and cleaning processes could be used to allow a limited range of fuels to use the fuel line, and similarly for the oxidiser line, or weather 4 lines should be providedLH2, RP-1, HTP, LOX. In tems of safety I'd brobably be happier if the carrier only carried HTP and RP-1....
I'm not sure whether minimising the fuel cost of the upper stage is liokely to give a significant saving - but certainly worth considering
Quote from: john smith 19
True, but it may have inherent benefits as well. While stressed skins are SOP for transport vehicles few have such a demanding temperature environment. High temperature strength quickly drops off but the structure REL plan to use (which IIRC originated from the X20 programme) lets you have a cold structure separate from a hot skin, even if the skin is not Pyrosic.
[...] unprotected Aluminium probably won't survive those conditions even briefly (although outside Beryllium it is the lightest metal) so some kind of TPS is going to be needed.  One little known fact is that NASA developed a reusable fastener design in the early 80's that could cope with securing 2 materials with wildly different (and even ansiotropic ) thermal expansion properties (like Aluminium and RCC) together.
I would have thought a more run of the mill composite would suffice, but Pyrosic would be a nice to test. - and skin attachment methods especially.

Quote from: john smith 19
Quote from: JCRM
I think the general shape is now fixed otherwise the mission analysis performed by Strathclyde would be wasted effort.
I was thinking about an array of circular nozzles, per the diagram - although that might be a two engine second stage and a one engine third stage

The details can make a significant difference. At least 1 Centaur stage was torn apart when one of the RL10 engines started and the other didn't, hence the fondness for a single big engine, rather than multiple smaller ones (not an option for the Saturn V 1st stage as the F1 was one of the biggest engines in the world already).
OTOH multiple engines give engine out ability, at the cost of gimballing or loss of net thrust due to non-parallel jets. as planned for on STS and used on Saturn V and SpaceX F9

Quote from: john smith 19
Quote from: JCRM
advantage of a payload return for some abort scenarios, and being launched in the UK for UK customers or Malta for European ones. What are the disadvantages?
The problem is those other launchers are already flying or are close to being able to sell a flight, and they don't fly often at that price.
Affordable reusability is very attractive. Look at it from an investors PoV. What are their USPs?
Ready now. No
Cheaper. No
First stage reusable. Unproven.

A "ready now" system isn't looking for the same type of investment - most of the costs have been sunk already, and the existing shareholders are going to want better return for their high risk pounds than the low risk investors get.
Cheaper? about the same - but reusability gives greater return the more it is reused, so a reusable has the potential, if there's a market.

Quote from: john smith 19
Quote from: JCRM
when used as a first stage the Orbital 500 is following a parabolic flight for 3-5 minutes. flying a 500kg payload with out an upper stage would increase that duration, replacing the upper stage with larger first stage tanks more so (but make reentry far more challenging, maybe it would need a more innovative TPS) - before I'm reminded that it can't be done because rockets aren't like Lego this vehicle is being designed as a "Lego rocket" where engines and payloads can be swapped out.
T3-4 minutes free flying is much more useful. Longer time is usually better in in sounding rocket work (as is lower acceleration. IIRC some of them hit a burnout acceleration of 18g). As the first stage of essentially a TSTO with starting speed of maybe M0.9, unless the first stage is going to be a very small fraction (Concorde cruised at M2.2 on an Al alloy skin) of the total needed to get to orbit a TPS is virtually certain.
Concord had to do it for hours though - the reference mission is less than three minutes accelerating to Mach 9, whilst climbing to 100Km, 10 minutes of free "flying" then 15 minutes of deceleration using lifting to reduce thermal load, mostly at twice the altitude of Concord. So yes, it would be hot, but nothing like an orbital craft. A "sounding rocket" mission would be hotter
Quote from: john smith 19
Quote from: JCRM
Given the requirement to be able to land with or without payload, I'm concerned the trim requirements might be excessive, however that big body flap might be enough
The body flap was a key feature of the Shuttle. It protected the SSME nozzles from both the high temperature of reentry air flow but also the side forces on them, which would probably have crumpled them.
and it needed it's full 16 degree deflection of pitch control

Quote from: john smith 19
With the US/Payload still on board it might actually be easier to land, although venting at least one of the US propellants would probably be a good idea for safety reasons.
US venting is part of the planned abort procedures

Offline john smith 19

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Re: Orbital Access
« Reply #16 on: 08/30/2017 12:15 AM »
I don't know if suitable seals and cleaning processes could be used to allow a limited range of fuels to use the fuel line, and similarly for the oxidiser line, or weather 4 lines should be providedLH2, RP-1, HTP, LOX. In tems of safety I'd brobably be happier if the carrier only carried HTP and RP-1....
I'm not sure whether minimising the fuel cost of the upper stage is liokely to give a significant saving - but certainly worth considering
Different oxidizers and fuels have different issues. If it's LOX and you don't run it in until the structure is fully purged with say dry N2 then ice forming on the line is not an issue. HTP plumbing normally needs a "passivation" procedure as most metals will catalyze its. If you're not having common propellants the usual rule of thumb is go for what gives the best Isp in the US.

Steve Pietron did a table of these but the only two that really stood out was Propyne, due to its triple bond, and the alcohol derivative, which was a derived from oat husks. Cheap, but a suspected carcinogen.  :(

It's one of the few areas where you can buy Isp fairly easily. The question is can you find an engine to burn it? They've been pretty quiet on exactly what they are planning to use for this.
Quote from: JCRM
I would have thought a more run of the mill composite would suffice, but Pyrosic would be a nice to test. - and skin attachment methods especially.

OTOH multiple engines give engine out ability, at the cost of gimballing or loss of net thrust due to non-parallel jets. as planned for on STS and used on Saturn V and SpaceX F9
Check the skin temperatures of the X15 when it hit M6+. Keeping that time short helps, but it goes only so far.  :(

STS had no engine out capability. 90% of T/O thrust was from the SRBs, which could not be shut down at all. For engine out you need enough engines that an engine out can be handled by all (or most) throttling up but not too much. That means five engines or more.
OTOH an HTO has more options. One engine aborts are well understood for aircraft. Its a RTLS and try again. I'll also not note that the Pegasus 1st stage has no TVC and neither do most passenger aircraft. Gimbaling a whole engine (even just the nozzle) needs a fairly heavy control system.

OTOH throttling, or changing mixture ratio, could be relatively low energy. 2 level MR on the later Apollo flights were responsible for 1/2 of the roughly 5% increase in payload sent to the moon, a powerful effect.

You have to have control surfaces to land the vehicle. You don't have to have TVC. Ideally you would want to point the 1st stage in the right direction using aerodynamic control surfaces before and during engine start and flight through the sensible atmosphere and essentially rely on the design staying in that attitude without TVC. You'd then use an RCS to deploy the US, turn round and start to descend, something like the X15.

Quote from: JCRM
A "ready now" system isn't looking for the same type of investment - most of the costs have been sunk already, and the existing shareholders are going to want better return for their high risk pounds than the low risk investors get.
Cheaper? about the same - but reusability gives greater return the more it is reused, so a reusable has the potential, if there's a market.
Sort of a chicken and egg question. Look at how often Pegasus has launched at those prices.  :(


Quote from: JCRM
Concord had to do it for hours though - the reference mission is less than three minutes accelerating to Mach 9, whilst climbing to 100Km, 10 minutes of free "flying" then 15 minutes of deceleration using lifting to reduce thermal load, mostly at twice the altitude of Concord. So yes, it would be hot, but nothing like an orbital craft. A "sounding rocket" mission would be hotter
If you've followed SABRESkylon you'll know that the inlet temperature at about M5 is already 1000c and it's well into its climb by then. You might also like to look up the skin temperatures of the X15 when it hit M6+.
Aluminium can be survive surprisingly high temperatures (It was used for the Agena combustion chamber) if it's cooled, due to its very high thermal conductivity. However 1000c is > 50% over most alloys melting points. If not actively cooled the skin would have to be pretty thick to carry away that much heat fast enough to radiate it from the cooler parts of the airframe. Might work but probably needs a CFD simulation to demonstrate it.

As for TPS if you don't want to use an ablative you have limited choices.  The 2 issues of all TPS are mass and oxidation resistance. In addition metallic TPS has issues with extra heat release due to it catalyzing heat release reactions on its surface and ceramics have brittleness problems.

Mass drives the use of thin sections, which are vulnerable to impact. Oxidation resistance means you need a protective coat. The maximum temperature of the coat, and it's fragility, set the real limits on whatever super duper material people are proposing (what keeps RCC from turning into "designer coal," as they said of attempts to make carbon fiber turbine blades)

Personally I'd love someone to try Autoclaved Aerated Concrete. It's available by the pallet load as a building material, can be sawed into sheets or machined into parts with a CNC router and (AFAIK) good to 1600c (IE the actual usable temperature of RCC, with it's oxidation resistant coat). It's a closed cell rigid ceramic foam, so it can float and is waterporoof, but it's 2x the density of the tiles on the Shuttle, although Grumman proposed it as their TPS for their design.

Quote from: JCRM
and it needed it's full 16 degree deflection of pitch control
The NASA history of the Shuttle said in early flights it deflected as much as 22 degrees.
Quote from: JCRM
US venting is part of the planned abort procedures
I'd expected that, but that pretty much rules out solid fuel US. No bad thing IMHO.
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline ringsider

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Re: Orbital Access
« Reply #17 on: 08/30/2017 07:25 AM »


I just noticed another filing by this company, that relates to the same time period as the first one above, but it was only filed 6 weeks ago.

The new one indicates they made an error in their first filing.

goo.gl/YQDRLP

This new one says that on 8.30.2016 they sold 108 shares at a total value of GBP 220,416.00, which works out at GBP 2,040 per share.

But in the original filing on 8.8.2016 they stated they had sold 29 shares for GBP 59,183.78 per share:

goo.gl/hqiI8m

Based on the second filing however, this isn't right - and if you divide 59,183.78 by 29 you get to the same share price as the new filing, GBP 2040.

In fact there is almost no rational way they could have sold 29 shares at almost GBP 60K a share and then turned around 3 weeks later and sold the same shares for 30 times less - no existing shareholder would allow that. They are all the same share class.

So it looks like they actually only raised about GBP 280K in August, not EUR 2,000,000... and sold about 57% of the company for that amount. And we are now 7 months later, so I wonder how much is left?

They did win a study for GBP 250K last spring, with several other partners, but I imagine that a) not all that amount is theirs simply because there are partners, and b) it is probably gone by now.

So I noticed they re-filed this 2016 document just recently (a year late), and I was right - the total raise was just GBP 59K in the first tranche and a total of GBP 280K overall.

I'm not 100% sure of their current financial status but that 280k is probably mostly gone by now, and the UK grant they had last year was a share of 250k, so that is probably gone as well. The current grant with ESA is also a share of the headline amount. They need a significant grant win or new equity in my opinion. I imagine the move to incorporate and IPO in Malta is underpinned by that need, although when you look at the types of firms listing on Prospects it's not a reassuring sign.

Noticeable that the heavy PR has dried up recently.

Offline ringsider

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Re: Orbital Access
« Reply #18 on: 08/31/2017 11:58 AM »
Interesting comment from one of the directors:-



Offline JCRM

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Re: Orbital Access
« Reply #19 on: 09/02/2017 12:18 AM »
OTOH multiple engines give engine out ability, at the cost of gimballing or loss of net thrust due to non-parallel jets. as planned for on STS and used on Saturn V and SpaceX F9
STS had no engine out capability. 90% of T/O thrust was from the SRBs, which could not be shut down at all. For engine out you need enough engines that an engine out can be handled by all (or most) throttling
STS-51F
Quote from: john smith 19
Quote from: JCRM
Concord had to do it for hours though - the reference mission is less than three minutes accelerating to Mach 9, whilst climbing to 100Km, 10 minutes of free "flying" then 15 minutes of deceleration using lifting to reduce thermal load, mostly at twice the altitude of Concord. So yes, it would be hot, but nothing like an orbital craft. A "sounding rocket" mission would be hotter
If you've followed SABRESkylon you'll know that the inlet temperature at about M5 is already 1000c and it's well into its climb by then.
Yes, the inlet air temperature, after the triple shock acceleration from freestream to Mach 5. Not the skin temperature - Skylon is expected to only reach 1100K on re-entry - with hotter cannards and leading edges.
Quote from: john smith 19
You might also like to look up the skin temperatures of the X15 when it hit M6+.
... at 30,000 meters. it reached about 500C, with some hot spots around twice that The x15 was designed to test re-entry conditions by flying fast and level altitudes- the Orbital 500 isn't designed to test re-entry conditions, so while it briefly does Mach 8 at that altitude before climbing and slowing to Mach 4 at 80km, it is doing that in a blunt body pose, not a streamline one - and on that first hot dip it's below 40km feet for less than 30 seconds.

At the end of the day, this is pointless speculation. If the next stage of the project is funded I'm sure Strathclyde will run their re-entry software over it, refine the shape, then work out what's hot and what's not.


(Edit, oops feet/meters mess up.)
« Last Edit: 09/02/2017 01:21 AM by JCRM »

Offline john smith 19

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Re: Orbital Access
« Reply #20 on: 09/05/2017 11:07 AM »
STS-51F
I stand corrected. Under certain circumstances the SSME's were indeed able to compensate for small thrust reductions, but one of the reasons mfg the SRBs was tough was to ensure very close thrust balance, which would have only been discovered during SRB ignition. When most people talk about "engine out" they mean throughout most of at least the first stage flight. A sub par thrust level in one of the SRB's would have been impossible to compensate for as they didn't throttle. You can make SRB's throttle, but it's very hard work.

Quote from: JCRM
Yes, the inlet air temperature, after the triple shock acceleration from freestream to Mach 5. Not the skin temperature - Skylon is expected to only reach 1100K on re-entry - with hotter cannards and leading edges.
You have that backward. The air is decelerated in the inlet, which causes the pressure and temperature rises.
I'll note that 1100K is 827C, That's well below the softening temperature of Titanium, but about 60% heavier than Aluminium. Given the design is an air launch assisted TSTO it might be the severe thermal issues that drove REL to go with Pyrosic don't apply

The question would be  how well it would survive short times at very high temperature, very high speed, air flow without burning.

Quote from: JCRM
... at 30,000 meters. it reached about 500C, with some hot spots around twice that The x15 was designed to test re-entry conditions by flying fast and level altitudes- the Orbital 500 isn't designed to test re-entry conditions, so while it briefly does Mach 8 at that altitude before climbing and slowing to Mach 4 at 80km, it is doing that in a blunt body pose, not a streamline one - and on that first hot dip it's below 40km feet for less than 30 seconds.
Except where they got shock/shock interference heating (Edney Type III and Type IV IIRC) where that goes to more like 4:1 or above, which is what sheared off the dummy SCramjet they were testing.
Quote from: JCRM
At the end of the day, this is pointless speculation. If the next stage of the project is funded I'm sure Strathclyde will run their re-entry software over it, refine the shape, then work out what's hot and what's not.
Probably. This is the stage to design out technical risks.

I like the concept, although there are very vague on what engines they are looking at.

I'm more concerned about the business model and the market.

Talk of vast low orbit constellations puts me in mind of Geostar, Orbcomm and Iridium, and not in a good way.  :(
« Last Edit: 09/06/2017 10:46 AM by john smith 19 »
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline JCRM

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Re: Orbital Access
« Reply #21 on: 09/13/2017 10:23 AM »
STS-51F
I stand corrected. Under certain circumstances the SSME's were indeed able to compensate for small thrust reductions,
The engine was shut down.
Quote from: john smith 19
but one of the reasons mfg the SRBs was tough was to ensure very close thrust balance, which would have only been discovered during SRB ignition.
Careful - you're skirting awfully close to calling a motor an engine.... ;p
Quote from: john smith 19
When most people talk about "engine out" they mean throughout most of at least the first stage flight.
The shuttle was designed to have one engine shut down, and either abort to orbit, or if the loss was too early in the flight to abort once around.

Engine out capability can mean the ability to complete the mission, but I was using it to mean "not fall out of the sky" - which for the Orbital 500 would be gain enough altitude to glide back to a runway.
Quote from: john smith 19
Quote from: JCRM
Yes, the inlet air temperature, after the triple shock acceleration from freestream to Mach 5. Not the skin temperature - Skylon is expected to only reach 1100K on re-entry - with hotter cannards and leading edges.
You have that backward. The air is decelerated in the inlet,
I disagree, but the discrepency is down to a different frame of reference. In flight the air is accelerated (and compressed) from rest to almost the speed of the vehicle. Relative to the engine it's decelerated, in a wind tunnel it's decelerated, and in most ways that matter there isn't a difference
Quote from: john smith 19
Given the design is an air launch assisted TSTO it might be the severe thermal issues that drove REL to go with Pyrosic don't apply
The severe thermal issues are during re-entry, from orbital velocity. The Orbital 500 doesn't have an air intake - unless it's carrying one as part of a test engine replacing the payload bay and engines, at which point the inlet material is the choice of the test engine developers.

The question would be  how well it would survive short times at very high temperature, very high speed air flow without deforming or burning.
Quote from: john smith 19
Quote from: JCRM
... at 30,000 meters. it reached about 500C, with some hot spots around twice that The x15 was designed to test re-entry conditions by flying fast and level altitudes- the Orbital 500 isn't designed to test re-entry conditions, so while it briefly does Mach 8 at that altitude before climbing and slowing to Mach 4 at 80km, it is doing that in a blunt body pose, not a streamline one - and on that first hot dip it's below 40km feet for less than 30 seconds.
Except where they got shock/shock interference heating (Edney Type III and Type IV IIRC) where that goes to more like 4:1 or above, which is what sheared off the dummy SCramjet they were testing.
the lesson here is don't go adding pointy bodies parallel to another that without planning for it. Skylon has the same issue, with it's wingtip nacelles, but they've planned for that and intend to have specialist materials in those areas. Where do you think dual shock interaction may occur on the proposed design?
Quote from: JCRM
At the end of the day, this is pointless speculation. If the next stage of the project is funded I'm sure Strathclyde will run their re-entry software over it, refine the shape, then work out what's hot and what's not.
[/quote]
On reviewing "Vehicle and mission design of a future small payload launcher", the mission design used some crude modelling to control the general heating (pp 8-11), and "A commercially driven design approach to UK future small payload launch systems" claims "an aerothermal model was developed by Fluid Gravity Engineering to calculate the heat loads and
wall    temperatures,    and    to    assess    the    TPS requirements  and  sizing"
Quote from: john smith 19
I like the concept, although there are very vague on what engines they are looking at.
I'd guess that's because they're not yet looking at specific engines - component selection being further along the design process (although with COTS being a priority for the approach, and engine performance being important to the vehicle it seems strange they just estimated an engine)
Now, with that rectangular cross-section wouldn't a linear aerospike look lovely? :p
Quote from: john smith 19
I'm more concerned about the business model and the market.

Talk of vast low orbit constellations puts me in mind of Geostar, Orbcomm and Iridium, and not in a good way.  :(
I find the prediction of nanosat congestion in 15 years rather depressing.
Predicting the future is difficult, but launch rates are rising, and payloads more so, but it's the same business model that all the other small sat launchers are using.

If one were looking to design an airframe to test fly an experimental engine, sharing development costs with a small sat launch system is attractive. Even if the program never turns an overall profit, it only needs to cover the launch costs, and the incremental cost between the test vehicle and the launch vehicle in order for it to have paid for itself and effectively be making money.

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