Complete Newbie

First of all, hello world! :handshake:

Well i'm interested in getting into this as a hobby, my questions are going to be a big vague so bear with me. Ultimately i'm after some reading material to teach me the basics (i've seen the links in the sticky but reading long articles on a computer screen makes my eyes bleed, so it's back to a good ol' fashioned book for me ), which will go on my ever increasing 'to read' list.

I've been recommended the 'Handbook of Model Rocketry' by G. Harry Stine and Bill Stine, could any of you vouch for it? To give you an idea of where i am at the minute i've got an A* in GCSE Physics (and the intention to take it at A Level), but i'm lost in terms of the subforums below this one, i get some of the basic principles but none of the maths - for instance, how do you calculate thrust? I heard someone on a youtube video say it's weight*acceleration, but that doesn't sound right to me since it would imply that if something's weightless it can have no thrust - so mass*acceleration sounds more likely, and also rings a bell with those pyramids we were taught to remember it (F=M*A, F/M=A, F/A=M). Specific questions? What are the units involved (metric, if possible ), how do you calculate how fast something would travel (when acceleration=0) from the thrust and how do you measure thrust in a stationary motor test? That should get us started

For a first project (when i eventually get some money) i'm thinking about a stationary hybrid rocket from scratch, experimenting with a few different fuels and nozzle designs - an idea somewhat influenced by this video, which is largely responsible for my interest in this to begin with.

Thanks for any and all help with anything above, hope you can understand it and i wasn't just rambling

First of all, welcome to the Forum and to the hobby.

Yes, Stine's Handbook is one of the best resources you could own. It will explain pretty much everything about the hobby. And don't worry about whether or not you have the physics background for the hobby - most don't and do fine with it. Actually, after being in the hobby for a couple of years, you WILL be able to claim to be a rocket scientist!

Seriously, my best advice is to:

* Pick up a couple of kits and build them. Start small (an Estes Alpha and Big Bertha are two really good kits to start with). Once you do have a rocket or two built, resist the urge (and it will be strong) to put the largest recommended motor in it. Trust me - that's a really good way to lose your first rocket, and the really fun part of the hobby is getting your rocket back and flying it again!

* Find a club near you where you can go to fly rockets. Flying with a group is a lot more fun than flying by yourself, and you don't have to find a field and get permission to fly there - they've already done that. Plus, you'll get a lot of advice from them that will teach you more than just book learning and trial and error.

* Read as much as you can here. Check out the other links to other rocket sites too.

* Ask questions! Don't be afraid to ask a question here - most everyone here loves to help a new rocketeer get started and will be happy to answer any questions you might have. Remember, the only stupid question is the one that remained unasked!

Superewza said:

For a first project (when i eventually get some money) i'm thinking about a stationary hybrid rocket from scratch, experimenting with a few different fuels and nozzle designs - an idea somewhat influenced by this video, which is largely responsible for my interest in this to begin with.

Thanks for any and all help with anything above, hope you can understand it and i wasn't just rambling

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O.k one of the most common misconceptions about rocketry is that model rocketeers make their own motors. In reality most of us use store bought motors that are avalible at your hobby shop or online. Many amatures dont realize the complexity of rocket motors (take a look at the "quassam rocket" thread to see what i mean) when an amature tries to make his own motor it will usually fail (watch some youtube videos if you want proof). I would HIGHLY RECCOMEND starting off with commercial made rocket motors. One you get certified as A level 2 then you can begin to make rocket motors.
Also welcome to the forum and rocketry in general.

Thanks for the suggestions! It may not be a necessity to have a background in Physics but it's something i enjoy doing and it's usually a great way to get your head around how something works. And i'll have a look for that thread, no better way to learn from your mistakes than having something blow up in your face

Superewza said:

Thanks for the suggestions! It may not be a necessity to have a background in Physics but it's something i enjoy doing and it's usually a great way to get your head around how something works. And i'll have a look for that thread, no better way to learn from your mistakes than having something blow up in your face

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Im glad that you arent stubborn like the other people we've tried to talk out of jumping straight to Experamental motors. Its great to have someone that will follow our advice and respect the hobby. Most people who ask about Homeade motors dont, like these threads:
https://www.rocketryforum.com/showthread.php?t=22773 and
https://www.rocketryforum.com/showthread.php?t=22986

Oh i'm more than happy to admit that i have a huge amount to learn, in anything (i have a motto that goes something like "the day i know enough is the day i'm ready to die"). So 'Experimental Motors' is another way of saying built from scratch? I noticed that that forum is locked, may i ask why the US Citizen requirement exists?

The U.S. government gets very nervous about sharing technology with foreigners. The technology export rules are called International Traffic in Arms Regulations, or ITAR for short. They are incredibly complicated and the penalties for violation are severe.

The company I work for makes aircraft lighting in the U.S. When we make a product for a military aircraft we have to be extremely careful what technical details we discuss with people who are not U.S. citizens or who are U.S. citizens but not actually on U.S. soil at the time the discussion is taking place. Both cases would be considered exporting technology and would be violations of the law. We are also forbidden to take restricted information out of the country without an export license even if no one else would ever see it. It is actually easier for me to sell you the part than it is for me to tell you how it works.

I had one meeting with a Brit where I sat on one side of the desk and me and another engineer sat across from him. He was the program manager responsible for selling this product and dealing with customers in Europe. Me and the other guy held up a drawing (so he could not see it) and he was asking us questions about the product. Our lawyer said we could answer any question regarding routine maintenance, but any querstion that crossed the line into operation of the product or repair was off limits. So we could tell him how to change the light bulb, but could not tell him details about how bright it was, etc.

So the people at the forum decided that something like experimental rocket motors just might fall under the ITAR restrictions. To be safe the discussion is limited to U.S. citizens. This keeps people out of prison.

there is a great series of videos on Apogee Rockets web site that takes you through all the steps.https://www.apogeerockets.com/getting_started.asp

Zeus-cat said:

-snip-

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Thanks for the explanation, fair enough i guess... so much for our 'special relationship'. We all know that was just an excuse for Regan to halt our HOTOL programme

And cheers for the link Humma, i'll check it out later

Zeus-cat said:

The company I work for makes aircraft lighting in the U.S.

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The company I work for makes aircraft and other delivery vehicles for all sorts of delightful "greetings" devices. All of our office buildings are loaded with non-US folks who are working here on various international programs, making it a collosal and constant PITA to have to close every door behind you until you hear the lock engage, pick up just about every piece of paper from your desk and lock it inside even if you are just popping into the RR for a minute, and secure your desktop (complete with password) if you take 3 steps out of your cubicle to pick something up from the copy machine. It is just part of doing business, ITARs and all, but it is pretty much impossible to explain why all this makes sense to anyone else who doesn't live in this world.

Zeus-cat said:

This keeps people out of prison.

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And I like not being in prison.

While all this stuff may be truly silly to impose on the people who pioneered rocketry (Tsiolkovsky was into this stuff before Goddard was, Germany taught us how to make rockets, etc.), it is nevertheless the situation we have to live with.

Superewza said:

I've been recommended the 'Handbook of Model Rocketry' by G. Harry Stine and Bill Stine, could any of you vouch for it?

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That is a great resource. Any of the editions would be a good starting place and you could take your time waiting to find a "bargain" price on the most recent edition.

Another good source of info is the old Estes handbook, the Alpha Book of Model Rocketry. Estes used to send these out free with mail orders, but more recently you can find it online (still free). Look for it at: https://www.ninfinger.org/rockets/nostalgia/alpha00.html (probably also posted at other sites)

For that matter, there is a ton of rocketry material at
https://www.ninfinger.org/rockets/rockets.html
https://www.ninfinger.org/rockets/ModelRocketry/ModelRocketry.html
https://www.spacemodeling.org/JimZ/estes.htm
https://plans.rocketshoppe.com/
This stuff is probably worth printing off and keeping, if you don't like squinting at screens.

Hope some of that helps. Do indeed keep coming back here with your questions--

Yes, G. Harry's "Handbook of Model Rocketry" is HIGHLY recommended... if any book is the 'bible' of model rocketry, it's the HBoMR...

You don't HAVE to be a physics major to fly model rockets, though if that's where your interests lie you can certainly pursue that endeavor... the HBoMR has a couple chapters dedicated to the physics and mathematics of flight, from a "laymans" viewpoint... (very descriptive). There's also chapters dealing with motors and the math behind them (describing the NAR motor designation system (letter-number-dash-number {and sometimes suffix}). There's also chapters on aerodynamics and shapes, multistaging, etc. and descriptions of all these design factors on performance, as well as stability, which is critically important for unguided rockets like ours...

Good luck! OL JR

The Harry G Stine book is excellent. It is a great resource for both new and experienced rocketeers.

Welcome to TRF! Sorry if this came out a bit long...

Superewza said:

I've been recommended the 'Handbook of Model Rocketry' by G. Harry Stine and Bill Stine, could any of you vouch for it?

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Definitely - it's basically required reading if you get even the slightest bit addicted to rocketry. I dunno what the libraries are like up your way, but I managed to find a slightly older edition in one of the Surrey libraries, which is handy if you don't want to spend money on the book or are just too impatient to wait for Amazon to deliver.

To give you an idea of where i am at the minute i've got an A* in GCSE Physics (and the intention to take it at A Level), but i'm lost in terms of the subforums below this one, i get some of the basic principles but none of the maths...

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Another book that might be worth reading, particularly if you're interested in hybrid motors, is 'Rocket Science and Spaceflight for Young Rocketeers' by Rick Newlands (amazon). Don't let the title put you off too much - the first few chapters are fairly basic space subjects, but the later chapters get into more meaty stuff about designing and testing hybrid rocket motors. It also goes into the maths a bit more, but it's all explained really well and is a more gentle introduction than, say, Rocket Propulsion Elements (which is also a good book, but IMO you'll need at least one year of A Level maths behind you before the maths starts making sense. Not to mention the price has gone up 25 quid since I bought it... )

I assume you're starting A Levels in September? If so, try and take the Mechanics module in maths, it covers some of the things you're asking about, and if you like physics you should enjoy it anyway...

For a first project (when i eventually get some money) i'm thinking about a stationary hybrid rocket from scratch, experimenting with a few different fuels and nozzle designs - an idea somewhat influenced by this video, which is largely responsible for my interest in this to begin with.

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Have a look at the Microhybrid (which you can get from Eclipse Rocketry here). It's basically a small hybrid motor that uses nitrous from little cylinders made for whipped cream dispensers, which is great for experimenting with different fuels. It's small and safe enough to static test in a decent sized garden, plus you can lob it in a rocket too. Here's an old vid of one of my test firings:

[YOUTUBE]fKi3jU3Stqc[/YOUTUBE]

Send me a PM if you want any more info about it - don't want to upset ITAR by discussing it in public.

Finally, if you can get yourself down to the Midlands this time next month, you should come along to the 'Festival of Rocketry'. It's shaping up to be the biggest UK launch event this year, and will be the best place to see what UK rocketry is like, talk to people and get questions answered, see some big rockets, look at some hybrid motors, and generally get talked into spending far too much money.

Cheers,
Phil

Thanks a lot WiK, the longer the better I've already seen the Festival of Rocketry on an astronomy forum, posted by someone involved in making the hybrid rockets for BGTT that i linked to in the OP. As for Libraries, well my dad works at Newcastle central (the one that was recently rebuilt), they'll probably have it. Takes me ages to get round to reading anything though so i might just buy it

Yeah, i'm officially starting A Levels in Sep., but i've done a few maths modules already since we started early (D1 and C1), didn't go brilliantly but i was definitely going to choose to do M1 when i get the chance. I'm thinking Maths, Physics then... well, the options sort of fall down as far as i'm concerned, it's Biology, Sociology or Philosophy and pretty much Law or Chemistry i think, Sociology looks rubbish in the first year and they've chosen all the religious Philosophy modules so i'm thinking Biology. I wasn't too good at Chemistry at GCSE but then i did miss most of the lessons for about a year, got a B overall. I've heard people say it's a good science to have along with at least one other, but i'm rather stumped at the minute. Anyway, i ramble - thanks for the advice

PS) As i understand it, those of us in the UK don't really have to worry about ITAR, do we? I find it unlikely that the US have a law against other countries sharing information with them

Superewza said:

Yeah, i'm officially starting A Levels in Sep., but i've done a few maths modules already since we started early (D1 and C1), didn't go brilliantly but i was definitely going to choose to do M1 when i get the chance. I'm thinking Maths, Physics then... well, the options sort of fall down as far as i'm concerned, it's Biology, Sociology or Philosophy and pretty much Law or Chemistry i think, Sociology looks rubbish in the first year and they've chosen all the religious Philosophy modules so i'm thinking Biology. I wasn't too good at Chemistry at GCSE but then i did miss most of the lessons for about a year, got a B overall. I've heard people say it's a good science to have along with at least one other, but i'm rather stumped at the minute. Anyway, i ramble - thanks for the advice

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C1 is quite a step up from GCSE maths, so I wouldn't worry too much if it took a little while to get into it.

As for the other subjects, if you're planning on going to university, go and look at the entry requirements for any courses you might be interested in. Obviously pick an A level subject you think you might enjoy, but if you're going for a science or engineering degree then the uni is going to be much keener on an applicant with maths, physics and chemistry than one with maths, physics and philosophy. It's definitely worth doing the research now, as taking the wrong A level subjects is the easiest way to stop yourself from getting on the degree course you really want.

PS) As i understand it, those of us in the UK don't really have to worry about ITAR, do we? I find it unlikely that the US have a law against other countries sharing information with them

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Outside of this forum, no (although there is an equivalent UK law, I don't have a clue about it). But since TRF is hosted in the US and owned by an American there's a pretty strict no-ex rule outside of the appropriate area. It's not really the way I'd like things, but this is definitely preferable to seeing any of my friends here getting locked up because of the forum. Better safe than sorry, and all that.

Cheers,
Phil

Equivalent UK law? I think it's called the Freedom of Information Act

Really though, thanks for all the advice - i'm definitely considering Chemistry but i'd be much more inclined if somebody were to say "alright, forget everything you learned at GCSE, this is proper Chemistry", which would help a lot with the stuff i missed/didn't understand at GCSE. That's not going to happen though, is it?

https://www.amazon.com/dp/0471326429/?tag=skimlinks_replacement-20

This might be more up your alley. This is the hard stuff but you have the math to understand it. I don't think a text book comes under that law. There are thousands of copies and it's basic knowledge.

Superewza said:

To give you an idea of where i am at the minute i've got an A* in GCSE Physics (and the intention to take it at A Level), but i'm lost in terms of the subforums below this one, i get some of the basic principles but none of the maths - for instance, how do you calculate thrust? I heard someone on a youtube video say it's weight*acceleration, but that doesn't sound right to me since it would imply that if something's weightless it can have no thrust - so mass*acceleration sounds more likely, and also rings a bell with those pyramids we were taught to remember it (F=M*A, F/M=A, F/A=M). Specific questions? What are the units involved (metric, if possible ), how do you calculate how fast something would travel (when acceleration=0) from the thrust and how do you measure thrust in a stationary motor test? That should get us started

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As a resource the internet is amazing, but sadly there is no internet police to be sure the content is good. That being said, if I make a mistake in this post I will have firmly planted my foot well into my throat.

Your intuition about the units is correct. Thrust has a magnitude and a direction and as such is a force. The units would either be pounds or newtons. Wikipedia has an article on thrust here (which like other internet sources is as terrible as it is useful). NASA has a blip about it here as well (their website is pretty fun to browse if you have not skimmed it before). As far as mistakes go, people will commonly use kilograms to measure weight in the metric system even though the term denotes mass. As a result the term weight frequently is used when mass was intended. This is my only real complaint about the metric system, that and I have no way to visualize what all the units mean since I have little practical experience with them.

Thrust as a subject generally is taught in relation to courses that address fluids or thermodynamics pending the institutions curriculum and the level of detail desired. If you are wanting to calculate how a system responds to said thrust, the complexity depends entirely on the system and the assumptions you use. It is not a simple task to build a precise model for a system and things will generally be done computationally as opposed to analytically.

Measuring thrust will be an instrumentation issue. If you are curious what type of things you would measure, I suggest you check out the various motor spec sheets on the NAR certified motors page.

Superewza said:

I've been recommended the 'Handbook of Model Rocketry' by G. Harry Stine and Bill Stine, could any of you vouch for it? To give you an idea of where i am at the minute i've got an A* in GCSE Physics (and the intention to take it at A Level), but i'm lost in terms of the subforums below this one, i get some of the basic principles but none of the maths - for instance, how do you calculate thrust? I heard someone on a youtube video say it's weight*acceleration, but that doesn't sound right to me since it would imply that if something's weightless it can have no thrust - so mass*acceleration sounds more likely, and also rings a bell with those pyramids we were taught to remember it (F=M*A, F/M=A, F/A=M). Specific questions? What are the units involved (metric, if possible ), how do you calculate how fast something would travel (when acceleration=0) from the thrust and how do you measure thrust in a stationary motor test? That should get us started

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F = M * A :: Newton = Kilogram * (Meter / Second^2)

I'm not the expert here but for a comprehensive understanding, should probably have some background in calculus as well as engineering statics and dynamics... And a computer

Integrate acceleration over time to get speed. Integrate speed over time to get position (distance).

Gravity is about 9.8m/s^2 so to get a 1Kg rocket to overcome gravity you need 9.8 Newtons of thrust underneath it. Any more force than that and it should accelerate upward. (modeled with an arrow pointing down representing gravitational force (weight), and arrow pointing up representing thrust.)

Then you get into aerodynamic drag as the rocket moves, which is another downward force which varies according to the speed of the rocket.

And that's why they invented the computer!

I find it unlikely that the US have a law against other countries sharing information with them

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*Voice of Apu from the Simpsons* Oh! I have been zinged and I love it!

Superewza said:

.....how do you calculate how fast something would travel (when acceleration=0) from the thrust....

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We just ran through a demonstration of this over on another thread
https://www.rocketryforum.com/showthread.php?t=22871

The question of how to calculate thrust gets a lot more complicated. For existing motors you can find thrust data online (lots of it at the NAR motor webpages). You would really only have to calculate thrust for brand new motors of your own design---is that what you are asking about?