This FAQ
(Frequently Asked Questions) is built up from
questions that people ask me or the AWARS group
from time to time. See also the Problems Page.
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| What
is PET? |
 |
PET, the material that plastic
fizzy drinks bottles are made from is
PolyEthylene Terephthalate or the polymer of
Ethylene Terephthalate. |
| Can
you make water rockets using other materials? |
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Water rockets have been made
from tin cans, larger plastic bottles (not PET)
and other things. PET is probably the safest
material to use as a water rocket though. |
| Do
I need a license to launch water rockets? |
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As far as we know so far, there
is no requirement for a license to launch water
rockets. However, if you go asking the wrong
people in authority, you may give them ideas of
another way to restrict people's activities in an
already oppressive society (next, they will be
telling us that you can't marry your own sister!
:-) |
| What
do I need to take with me when I go launching
water rockets? |
|
Rockets (including chutes and so
on), water, a pump, a launcher, a release cord, a
whistle (or air horn to draw people's attention),
possibly a camera and a stopwatch. Sometimes,
children and other adults :-) |
| What
is a safe place to launch a water rocket? |
|
A flat ground, away from overhead power cables, cars or
lorries, away from houses and other property that
may be damaged by a rocket falling from the air.
See the safety page for a guide about safety.
Also, make sure that anyone who is within the
possible landing area or is reasonably likely to
wander into it knows what to expect. |
| What
is a safe distance from a launcher? |
|
Before the rocket is fired and
assuming that there are no metal or heavy parts
to the rocket (ie, it is just a pop bottle with
plastic fins and plastic nose cone et cetera) a
distance of 20 feet should be reasonably safe if
you are pressurising to 100 psi. You should
remember that you should wear goggles. There have
not been any reports of rockets bursting and
spreading debris further than around 10-15 feet
so, like any risk assessment, you should use your
judgement and err on the side of safety. |
| Why
should I use a computer model? |
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A computer model can tell you
things about a flight that can save you effort
(and embarrassment if you are in the wrong
predicament). A computer model can tell you how
much water to use for a given nozzle size and how
much the rocket should weigh. It can tell you the
best angle to launch at if you are launching for
maximum distance and let you know if the rocket
will behave unexpectedly (such as a critical
nozzle diameter/weight combination) and alert you
to safety issues such as spectators needing to be
at least a certain distance away. |
| Will
a computer model cost me anything? |
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There is at least one commercial
computer model that I know of but the rest are
effectively free to use once you have downloaded
them. If you use mine, you will need to register
it by sending me a picture postcard of somewhere
close to where you live (but no money). |
| Do
you have to be a PhD to use a computer model? |
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No. I know that some PhDs do use
my computer model but I have designed it with two
levels of user in mind. It has a novice version
with only the basic measurements on it and this
also has a Wizard to help the user input the data
along with further explanations as to the meaning
of each number - this is suitable for juniors
(age 7 to 11). Then there is the Expert level
where the user can change anything (s)he likes
including which planet to launch from and which
gas to use. |
| Which
computer model should I choose? |
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There are a number of models,
each with benefits. If you want a model for a PC,
that you can use off-line then your best bet is
to choose mine (but I would say that wouldn't I
:-). There are also versions for Macs and one for
a spreadsheet so that you can see the numbers for
each modelled value as it progresses through the
flight. There is also an online version if you
don't want to download anything as all of the
computing is done at the server end. Look at the
Links page for links to these other models and
make your decision based upon all of the
available information. |
| Do
I need the HTML help pages to be able to use the
computer model? |
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No. The water rocket computer
model is completely self contained and will work
perfectly well without the HTML help. The HTML
help provides a more in-depth view into the
working of the model and is complete with
examples and so on that the help on the computer
model itself cannot do. They are also in a number
of languages so that the browser can display or
print out the pages without me having to worry
about providing different versions of the model. |
| What
do I need to do to install the water rocket
computer model? |
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Assuming that you intend to
install it on a PC, all you need to do is to
download the ZIP file, decompress it and put it
into a directory (folder) of its own. It does not
need any .DLLs (Dynamic Linked Libraries) to work
and therefore it can be moved anywhere. To make
using it easier on a Windows machine, you can
create a shortcut (by right-clicking and
selecting Create Shortcut from the menu) and then
put that wherever it is convenient. |
| What
do I need to do to register the water rocket
computer model? |
|
All you need to do to register
the water rocket computer model is to send me a
picture postcard of somewhere close to where you
live. I am not interested in taking money from
people as it is both a hassle for the sender and
the recipient (I would have to convert it into UK
pounds and that costs more than it is worth).
Postcards are almost everywhere and so is a
postal system of some sort. The address details
are in the README.TXT file. |
| What
do I need to do to uninstall the water rocket
computer model? |
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Remove (delete) the files that
you installed (there are no registry data or
files that are outside its working directory to
delete or change) and, if you installed it in its
own directory and have not put anything you want
to keep in there, delete the directory as well.
If you are not sure about deleting files or
directories then don't. Ask someone who does know
as it is better to be safe than sorry. |
| What
does AWARS stand for? |
|
Actually, We
Are Rocket Scientists.
A while ago, we decided by a vote on the name for
the e-mail group and this was the result. |
| What
is the AWARS WebRing? |
|
The AWARS WebRing puts its
websites into what is effectively a circle of
sites so that you can go from one to the next (or
previous and so on) without having to use search
engines and so on.. The sites are vetted so that
they all contain relevant Water Rocket
information so that the user knows that (s)he is
going to find things that are relevant to water
rocketry. A certain amount of traffic goes via
the WebRing and I always advise people to have a
look at other's sites before making up their
minds on issues (such as which type of launcher
should I build and so on). |
| Which
countries have water rocketeers? |
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So far, to my knowledge, the
following countries have people in them that do
water rocketry: New Zealand; Australia; Japan;
Taiwan; Malaysia; Singapore; Thailand; India;
South Africa; Sweden; Norway; Denmark; Italy;
Germany; Belgium; The Netherlands; France;
England; Scotland; Wales; Ireland; Brazil;
Argentina; Colombia; Mexico; USA; and, Canada. |
| What
is the altitude record for a water rocket? |
|
1060 feet above ground level set
by Bruce Berggren on 3rd July 1998 using a two
stage rocket with Carbon Dioxide as the gas. |
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