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This book is a great resource, and I would recommend it to to any amateur model rocketry fan. I'm starting University in September as an adult student of Compu

This book is a great resource, and I would recommend it to to any amateur model rocketry fan. I'm starting University in September as an adult student of Computer Science and I'm planning to start a model rocketry society with the goal of putting a 9ft tube above the Karman line and recovering it safely. I'm still deciding on fuels, but I'm strongly considering a hypergolic combination of catalyzed pure hydrogen peroxide and kerosene (I've already been granted a recipient competent authority from the explosives department for the storage and transport of usable quantities these for the use in a model rocket). The primary reason for hypergolic fuels is because it doesn't require a complex combustion chamber / ignition set up. You can mix them together at ambient pressure and temperature and they will spontaneously combust producing heat, steam and pressure. If you can safely handle the dangerous fuels it's a much easier route to a liquid fueled rocket engine. One of the difficulties in the UK is going to be finding somewhere to launch from: we don't have large swathes of unowned, unmonitored land and the restrictions the CAA (rightfully) place on launching near cities means that it'll have to be out in the sticks somewhere. I'll probably have to convince a farmer to let us blow up a couple rockets on the back of a fallow field a few times before we get a successful launch off the ground. I'm trying to plan as much as possible and get all the requisite licenses (I already have a CAA unmanned surveillance drone operator ID, as well as exemption from the need for a flyer ID because I have my flight competency certificates, and exemption from the 400ft amateur flight ceiling as long as I issue a NOTAM (notice to airmen) 1 week before any test flights, and I'm insured by the UK Rocketry Association) in the hopes that people will "take me seriously" when I found the society. I'm also working behind the scenes to set up partnerships. I've been in contact with Starchaser Industries and a few other aerospace companies nearby to have them sponsor the program, show us around their rocketry factories and hopefully give us contacts at their company we can bounce ideas off to see if there's anything we've missed, or any hazards we are hugely mispredicting.

Mvandenbergh 6y ago
There's a proposed spaceport in Sutherland, I suspect that the landowners will let you launch from there.
- helldritch 6y ago
  Cheers for this, I'll get in contact with them over the next month when I have some more concrete plans. I was thinking it would end up being the peak district/lakes district/Lancashire moors/Scottish highlands we would be launching from.
  - arethuza 6y ago
    The 'spaceport' in Sutherland is quite a long way from actually being operational: https://www.bloomberg.com/news/articles/2020-03-17/the-u-k-space-agency-has-a-scottish-peat-bog-problem https://www.bloomberg.com/news/articles/2020-03-17/the-u-k-s...
    - dmurray 6y ago
      He only needs a field and benevolent landowners though, not the rest of the spaceport infrastructure.
      - helldritch 6y ago
        This is pretty much right on the money. The expected worst-case failure state would be a rupture in the Kerosene canister resulting in a high pressure, high heat ignition. Infrastructure and support needs are minimal, spatial radius needs are maximal. There would be bits of rocket everywhere in a 20m radius (which we would be dutiful in picking up since it's useful to study for next time) and there is unlikely to be any sort of crater, but there would be a small kerosene fire we would have to put out (so providing and testing fire suppression equipment in the form of extinguishers and blankets will be important). Realistically, we'll be flying something around the 30-40KG mark so we'll have to get it certified by the CAA: http://www.largemodelassociation.com/resources/over-20kg-scheme/over-20kg-revision/ http://www.largemodelassociation.com/resources/over-20kg-sch... I feel like with a youthful charm and the right paperwork from all the respective government divisions (The Explosives Division at the Health and Safety Executive, a certified model design from the Civil Aviation Authority, and our insurance as operators / flyers with the CAA) it won't be too hard to talk a field landowner in to it, in return for a token payment and an offer of a few cool afternoons seeing model rocket launches on the back-end of one of their fields.
areoform 6y ago
Hey there, if you can drop an email in your profile, or reply to this with one, I can hook you up with people that let you rent a satellite and run whatever code/observations you want. :) Kinda like AWS, but in space. Thought you might be interested.
- pixelface 6y ago
  this sounds really interesting and i'd imagine a bunch of us are very curious for a quick rundown on it despite not having an immediate need for it ourselves. care to elaborate?
  - d_silin 6y ago
    Have a look: https://www.exodusorbitals.com https://www.exodusorbitals.com
- helldritch 6y ago
  Hi! Please can you send the email to: 52bdec35-22f4-4488-bac5-d055a9fff4b8@helldritch.anonaddy.com? Thanks a lot for this, it sounds useful, I wonder if we could time the launch so that the satellite could receive telemetry (as a back up to the integrated avionics failing due to rapid pressure or temperature changes, or shock)
m4rtink 6y ago
Copenhagen Suborbitals does launches over water from a floating platform - maybe a similar arrangement could be done ?
- shireboy 6y ago
  This was my first thought too. Abandoned oil platform or big enough barge off the coast to get around some of the land constraints in UK? Be sure to let HN know when you launch this thing, OP.
PoachedSausage 6y ago
You could try talking to the people from the Westmidlands Branch of BIS: https://www.bis-space.com/branches/regional/bis-west-midlands-home-page https://www.bis-space.com/branches/regional/bis-west-midland... I went to some talks organised by them a few years ago. Many of the members worked on rocket propulsion for a local company and had connections to the Rocket Propulsion Establishment.
hoorayimhelping 6y ago
>If you can safely handle the dangerous fuels it's a much easier route to a liquid fueled rocket engine. This kind of glosses over the whole hypergolic fuels are necessarily poisonous toxins that boil your skin if you touch them. To react with each other so quickly, they basically have to react with just about everything else as well - including human saliva, the liquid on eyeballs, and the liquid in your lungs. This (extremely 60s styled) video is full of useful information about how dangerous hypergols are: https://www.youtube.com/watch?v=Zha9DyS-PPA https://www.youtube.com/watch?v=Zha9DyS-PPA
- helldritch 6y ago
  In general, I would agree with you. If you're dealing with umsymettrical-dimethylhydrazine and dinitrogen tetroxide, you're going to be in a world of pain trying to produce them, handle them and get them close enough to use in an engine without being so close that the fumes spontaneously ignite. Not to mention that the dinitrogen tetroxide boils at ambient temperatures, etc, etc. Obviously, I was glossing over the danger (not something I do in real life when handling dangerous fuels, but probably something I do when writing a short comment on Hacker News) and anyone seeking to work on Rocket Engines needs to ensure that they consult with subject matter exports before, during and after any construction or launch preparations begin. ... With that disclaimer out of the way, in the grand scheme of dangerous fuel and oxidisers combinations, Kerosene and Hydrogen Peroxide are significantly safer to handle than traditionally used hypergolic mixtures: - They are both liquids at ambient pressures and temperatures (don't underestimate the value of not needing highly pressurised canisters - above 2000psi in many cases - and cryogenic equipment, that's all mass you don't need to lift and failure states you don't need to control for) - Storage and deployment of AVTUR (Aviation Turbine Fuels) is a well understood procedure with pre-certified canisters. - Hydrogen Peroxide at sub-90%, and especially at sub 70%, purities is reasonably safe to store and handle, especially if you store it in an inhibited state and you're willing to have a suboptimal hypergolic reaction in return for a safer handling procedure. - The pressures and temperatures created when reacting these two liquids together in a combustion chamber are extreme, but not so extreme as to be outside the remit of an amateur team. This all doesn't mean that these are safe to handle - and failing to properly respect rocket fuel results in death for yourself and others - but it does mean that they're safer to handle. In a perfect world I would manufacture solid state rocket propellants, but in addition to the negatives of not being throttle-able and being hard to early-terminate, manufacture of solid rocket motors is a criminal offence in the United Kingdom and getting an explosives certificate is a long, daunting task.
growlist 6y ago
Good luck with this - nice to see a UK rocket following the Black Arrow tradition of HTP + kerosene! Have you thought about crowdfunding? I'd happily chuck in a tenner.
roach23 6y ago
As a working engineer in the aerospace industry with an amateur rocketry background, I highly recommend that you refine the scope of your project before you sink in a lot of resources. Iterating on high power solid rockets w/ parallel development on a small scale pressure-fed liquid is probably the most direct path to success. To launch a "9ft tube above the Karman line" you need - airframe structural design & analysis, avionics development & testing, recovery system " ", etc. The work that goes into a flight-ready airframe (separate from engine development) is massive. I don't know how to impress the scale of the project you're proposing, but you may want to take a look at some of the university teams attempting something similar: http://masa.engin.umich.edu/ http://masa.engin.umich.edu/ (I'm not affiliated with UMich). Something to takeaway is how long it's taken to iterate on their systems, despite the steady stream of motivated students and university support/infrastructure. I don't mean to be negative, but there needs to be a path forward if you're going to make the kind of progress you want. Again, I strongly suggest that you start flying smaller, simpler solid rockets now to iterate on airframe design and build flight experience as you consider liquid design choices.
- helldritch 6y ago
  Cheers for this! Don't worry about the negativity, it's something I've come to expect from subject matter experts since this is a very long process I'm going down fraught with danger and legislation. One of the issues with solid rocket motors is that in the UK we can't manufacture our own solid rocket motors under the 1875 explosives act (supplemented by the EU Directive 2014/28/EU), so we have to purchase off the shelf rocket motors which are available in the UK. Flying in an air frame with these has several key issues: It won't be a solid test bed for our air frame weight, the centre of gravity will be offset, they aren't throttle-able, even the high specific impulse motors tend to have very short (sub 10 seconds) burn times, they don't generate shock cones, etc. One of my personal inspirations is the UCSRPL: http://www.uscrpl.com/ http://www.uscrpl.com/ I imagine we'll have to follow in their footsteps: progressively more complex builds following on from a relatively simple starting point. The plan is to use as many pre-existing resources as possible, this means: - Using purchased fuel and oxidiser combinations instead of synthesis - Working on a software (virtualising the hardware) test bed for avionics, then progressing to breadboards, then to purchasing PCBs. It's worth mentioning that I will be a student of Computer Science, but I'm going in to this with a significant experience of real time programming and PCB design - previous companies I've worked at had embedded systems. - Using a simple system for recovery, most likely pressure deployed drogues fitted in the air frame cone, and an emitter which enables us to find it post touchdown. I also understand that it's likely going to take the majority of my degree to get this done. If we don't make it to the Karman line: that's also fine. I'm not daunted by the possibility of failure, I'm excited by it. We learn a lot from failure. The goal is to go as far as we can and develop our skills through iteration.

Mvandenbergh 6y ago

There's a proposed spaceport in Sutherland, I suspect that the landowners will let you launch from there.

helldritch 6y ago
Cheers for this, I'll get in contact with them over the next month when I have some more concrete plans. I was thinking it would end up being the peak district/lakes district/Lancashire moors/Scottish highlands we would be launching from.
- arethuza 6y ago
  The 'spaceport' in Sutherland is quite a long way from actually being operational: https://www.bloomberg.com/news/articles/2020-03-17/the-u-k-space-agency-has-a-scottish-peat-bog-problem https://www.bloomberg.com/news/articles/2020-03-17/the-u-k-s...
  - dmurray 6y ago
    He only needs a field and benevolent landowners though, not the rest of the spaceport infrastructure.
    - helldritch 6y ago
      This is pretty much right on the money. The expected worst-case failure state would be a rupture in the Kerosene canister resulting in a high pressure, high heat ignition. Infrastructure and support needs are minimal, spatial radius needs are maximal. There would be bits of rocket everywhere in a 20m radius (which we would be dutiful in picking up since it's useful to study for next time) and there is unlikely to be any sort of crater, but there would be a small kerosene fire we would have to put out (so providing and testing fire suppression equipment in the form of extinguishers and blankets will be important). Realistically, we'll be flying something around the 30-40KG mark so we'll have to get it certified by the CAA: http://www.largemodelassociation.com/resources/over-20kg-scheme/over-20kg-revision/ http://www.largemodelassociation.com/resources/over-20kg-sch... I feel like with a youthful charm and the right paperwork from all the respective government divisions (The Explosives Division at the Health and Safety Executive, a certified model design from the Civil Aviation Authority, and our insurance as operators / flyers with the CAA) it won't be too hard to talk a field landowner in to it, in return for a token payment and an offer of a few cool afternoons seeing model rocket launches on the back-end of one of their fields.

areoform 6y ago

Hey there, if you can drop an email in your profile, or reply to this with one, I can hook you up with people that let you rent a satellite and run whatever code/observations you want. :) Kinda like AWS, but in space. Thought you might be interested.

pixelface 6y ago
this sounds really interesting and i'd imagine a bunch of us are very curious for a quick rundown on it despite not having an immediate need for it ourselves. care to elaborate?
- d_silin 6y ago
  Have a look: https://www.exodusorbitals.com https://www.exodusorbitals.com
helldritch 6y ago
Hi! Please can you send the email to: 52bdec35-22f4-4488-bac5-d055a9fff4b8@helldritch.anonaddy.com? Thanks a lot for this, it sounds useful, I wonder if we could time the launch so that the satellite could receive telemetry (as a back up to the integrated avionics failing due to rapid pressure or temperature changes, or shock)

m4rtink 6y ago

Copenhagen Suborbitals does launches over water from a floating platform - maybe a similar arrangement could be done ?

shireboy 6y ago
This was my first thought too. Abandoned oil platform or big enough barge off the coast to get around some of the land constraints in UK? Be sure to let HN know when you launch this thing, OP.

PoachedSausage 6y ago

You could try talking to the people from the Westmidlands Branch of BIS: https://www.bis-space.com/branches/regional/bis-west-midlands-home-page https://www.bis-space.com/branches/regional/bis-west-midland... I went to some talks organised by them a few years ago. Many of the members worked on rocket propulsion for a local company and had connections to the Rocket Propulsion Establishment.

hoorayimhelping 6y ago

>If you can safely handle the dangerous fuels it's a much easier route to a liquid fueled rocket engine. This kind of glosses over the whole hypergolic fuels are necessarily poisonous toxins that boil your skin if you touch them. To react with each other so quickly, they basically have to react with just about everything else as well - including human saliva, the liquid on eyeballs, and the liquid in your lungs. This (extremely 60s styled) video is full of useful information about how dangerous hypergols are: https://www.youtube.com/watch?v=Zha9DyS-PPA https://www.youtube.com/watch?v=Zha9DyS-PPA

helldritch 6y ago
In general, I would agree with you. If you're dealing with umsymettrical-dimethylhydrazine and dinitrogen tetroxide, you're going to be in a world of pain trying to produce them, handle them and get them close enough to use in an engine without being so close that the fumes spontaneously ignite. Not to mention that the dinitrogen tetroxide boils at ambient temperatures, etc, etc. Obviously, I was glossing over the danger (not something I do in real life when handling dangerous fuels, but probably something I do when writing a short comment on Hacker News) and anyone seeking to work on Rocket Engines needs to ensure that they consult with subject matter exports before, during and after any construction or launch preparations begin. ... With that disclaimer out of the way, in the grand scheme of dangerous fuel and oxidisers combinations, Kerosene and Hydrogen Peroxide are significantly safer to handle than traditionally used hypergolic mixtures: - They are both liquids at ambient pressures and temperatures (don't underestimate the value of not needing highly pressurised canisters - above 2000psi in many cases - and cryogenic equipment, that's all mass you don't need to lift and failure states you don't need to control for) - Storage and deployment of AVTUR (Aviation Turbine Fuels) is a well understood procedure with pre-certified canisters. - Hydrogen Peroxide at sub-90%, and especially at sub 70%, purities is reasonably safe to store and handle, especially if you store it in an inhibited state and you're willing to have a suboptimal hypergolic reaction in return for a safer handling procedure. - The pressures and temperatures created when reacting these two liquids together in a combustion chamber are extreme, but not so extreme as to be outside the remit of an amateur team. This all doesn't mean that these are safe to handle - and failing to properly respect rocket fuel results in death for yourself and others - but it does mean that they're safer to handle. In a perfect world I would manufacture solid state rocket propellants, but in addition to the negatives of not being throttle-able and being hard to early-terminate, manufacture of solid rocket motors is a criminal offence in the United Kingdom and getting an explosives certificate is a long, daunting task.

growlist 6y ago

Good luck with this - nice to see a UK rocket following the Black Arrow tradition of HTP + kerosene! Have you thought about crowdfunding? I'd happily chuck in a tenner.

roach23 6y ago

As a working engineer in the aerospace industry with an amateur rocketry background, I highly recommend that you refine the scope of your project before you sink in a lot of resources. Iterating on high power solid rockets w/ parallel development on a small scale pressure-fed liquid is probably the most direct path to success. To launch a "9ft tube above the Karman line" you need - airframe structural design & analysis, avionics development & testing, recovery system " ", etc. The work that goes into a flight-ready airframe (separate from engine development) is massive. I don't know how to impress the scale of the project you're proposing, but you may want to take a look at some of the university teams attempting something similar: http://masa.engin.umich.edu/ http://masa.engin.umich.edu/ (I'm not affiliated with UMich). Something to takeaway is how long it's taken to iterate on their systems, despite the steady stream of motivated students and university support/infrastructure. I don't mean to be negative, but there needs to be a path forward if you're going to make the kind of progress you want. Again, I strongly suggest that you start flying smaller, simpler solid rockets now to iterate on airframe design and build flight experience as you consider liquid design choices.

helldritch 6y ago
Cheers for this! Don't worry about the negativity, it's something I've come to expect from subject matter experts since this is a very long process I'm going down fraught with danger and legislation. One of the issues with solid rocket motors is that in the UK we can't manufacture our own solid rocket motors under the 1875 explosives act (supplemented by the EU Directive 2014/28/EU), so we have to purchase off the shelf rocket motors which are available in the UK. Flying in an air frame with these has several key issues: It won't be a solid test bed for our air frame weight, the centre of gravity will be offset, they aren't throttle-able, even the high specific impulse motors tend to have very short (sub 10 seconds) burn times, they don't generate shock cones, etc. One of my personal inspirations is the UCSRPL: http://www.uscrpl.com/ http://www.uscrpl.com/ I imagine we'll have to follow in their footsteps: progressively more complex builds following on from a relatively simple starting point. The plan is to use as many pre-existing resources as possible, this means: - Using purchased fuel and oxidiser combinations instead of synthesis - Working on a software (virtualising the hardware) test bed for avionics, then progressing to breadboards, then to purchasing PCBs. It's worth mentioning that I will be a student of Computer Science, but I'm going in to this with a significant experience of real time programming and PCB design - previous companies I've worked at had embedded systems. - Using a simple system for recovery, most likely pressure deployed drogues fitted in the air frame cone, and an emitter which enables us to find it post touchdown. I also understand that it's likely going to take the majority of my degree to get this done. If we don't make it to the Karman line: that's also fine. I'm not daunted by the possibility of failure, I'm excited by it. We learn a lot from failure. The goal is to go as far as we can and develop our skills through iteration.